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Thursday, 27 June 2013
Speedlite Modifiers & Lack Thereof
Mood:  quizzical
Topic: Photography

I was shooting some portraits the other day a little later in the day than I had originally wanted to.  As a result the sun was a bit harsher and I found I had more trouble than expected getting enough light out of my modified speedlites to balance the ambient background.

When I got back to the studio I wondered whether I could have eeked out a bit more power by using a different setup or modifier.  It dawned on me that while I have used all of the modifiers I have in my arsenal at one time or another, I never compared them under identical conditions.  I recall Don Chick once suggesting to those of us attending his talk on portraits that we should experiment with an egg to understand what different lighting setups did, so we could use them more effectively on a real shoot. 

So, while I did not use an egg, I did try to answer two questions in a more controlled, apples-to-apples way:

     a) How much maximum light do I lose with various modifiers?

     b) How much "softening" does each technique offer? 

POWER LOSS EXPERIMENTS  

I limited my setup to one or two Canon 580 EXII speedlites with and without modifiers.  I did the whole thing inside and while the ceilings and floors were white, this did not affect my results except for the Rogue Flash Bender, which of course relies on bouncing light off the ceiling.  And lastly, while I tried to be consistent from shot to shot, I did not take the time to be super precise, but I estimate the error from this at no more than 1/3 of a stop.

The first step was to pull up the spec output from the speedlite manual at different settings.  At a power of 1/1, ISO=100, the spec output at different distances and manual zoom settings is as follows:

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     28 mm    f/20    f/14    f/10      f/7       f/5

     50 mm    f/28    f/20    f/14      f/10     f/7

     105 mm  f/38    f/28    f/20      f/14     f/10   

The first step then was to use a light meter and measure the output of an actual speedlite and see if I produced the spec result. Using two different speedlites and the 105 mm results repeated multiple times, I got these results:

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     28 mm    f/18    f/14    f/10      f/7       f/5

     50 mm    f/22    f/18    f/13      f/9     f/7

     105 mm  f/30    f/22    f/14      f/11     f/8

The results were at spec within measurement error at 28 mm zoom, but at the highest (105 mm) zoom, I consistently measured a lower output than spec even on my newest speedlite by more than 1/2 stop. 

WIDE (DIFFUSION) PANEL  [ 1-2/3 Stop Loss ] 

The simplest modifier is to simply pull out the built in "wide panel" and place it over the flash.  The manual describes this as extending the zoom coverage to 14 mm.  The measured output results were:  

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     14 mm    f/9      f/7      f/5.6      f/4      f/2.8

Comparing to the 28 mm zoom results, putting the wide panel in position appears to reduce the light output straight ahead by about 5/3 stops. 

HIGH SPEED SYNC  [ 1/3 to 2/3 Stop Loss ]   

The next most obvious modifier, likely to be invoked by necessity in bright light is to use high speed sync (HSS mode on speedlite) to be able to use shutter speeds about 1/250 or 1/300. The trouble here is that while below the camera sync speed, the light from the flash on the subject is pretty much independent of the shutter speed letting you control the flash light with aperture and ambient with shutter speed. At speeds faster than the sync speed the light from the flash will also be dependent on the shutter speed so balancing becomes more complicated. The measured output for one speedlite in HSS mode at power setting of 1/1 and constant zoom of 28 mm, the results were:

     SHUTTER     5 ft     7 ft     10 ft     14 ft     20 ft

     1/320          f/16    f/11     f/9       f/6.3    f/5.4  

     1/640          f/13    f/10     f/6.3    f/5.6    f/3.2   

At a shutter speed just above the sync speed at 1/320 the effective light output was measured about 1/3 stop under the non-HSS measurement for the same zoom setting.  At a shutter speed of 1/640 the effective light was measured about 2/3 stop down.    

TWO SPEEDLITES  [ + 1 Stop Gain ] 

The next "modifier" was to mount two speedlites on a common bracket and fire them together.  I used a Photoflex Dual Shoe Flash Adapter.   These results were as expected.  

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     28 mm      -        -        f/13      f/8       f/5

     105 mm  f/45    f/32    f/22      f/16     f/10  

The measured output was about double what it was with one light, that is, an increase in light by about 1 stop.            

ULTIMATE LIGHT BOX  [ 1-1/3 Stop Loss ]    

My next modifier was Harbor Digital Design Ultimate Light Box. Again the measurements were of one speedlight, set at power 1/1 and measured for ISO=100. The results were:  

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     28 mm    f/11    f/9      f/6.3     f/4.5    f/3.2

     105 mm  f/11    f/9      f/6.3     f/5       f/3.2   

As compared to the 28 mm zoom actual, the loss by adding the Ulitmate Light Box modifier is about 4/3 of a stop, so you lose a little over half of the light.  The other thing you notice is that the box does a great job of diffusing the light.  Adjusting the speedlite zoom had no effect on the measured output from the box.   

DOUG BOX LOCATION LIGHT BOX  [ 1-1/3 Stop Loss ]  

My next modifier was a Doug Box Location Light Box.  As with the Ultimate Light Box, adjusting the speedlite zoom had no effect on the measured output of the box, so I have only included the 28 mm zoom results below:        

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     28 mm    f/13    f/9      f/6.3     f/4.5    f/3.2   

At the closest distance of only 5 feet (pretty close for a box of this size) the loss appears to be down only about one stop, but at greater distances (7 feet and beyond), the drop is more consistently about 4/3 of a stop, similar to the Ultimate Light Box.   

ROGUE FLASHBENDER (LARGE)  [ 2-1/2 Stops Loss ]   

My next modifier was a large Rogue Flashbender.  Since this is not as simple as the other modifiers, I tried to use it in what could be a typical fashion.  I set the speedlite to a zoom of 50 mm, and pointed it straight up at the ceiling.  I attached the Rogue Flashbender and kept it fairly flat.  In measuring the light output, I tried to block contributions from the ceiling to measure mostly straight forward reflections. 

     ZOOM           5 ft     7 ft     10 ft     14 ft     20 ft

     50 mm UP     f/7.1    f/6.3   f/4.5    f/3.2     f/2.2    

These results indicate about 5/2 stops (2-1/2 stops) loss from the 28 mm actual baseline.  Obviously these results can be varied significantly by tilting the speedlite at a different angle or shaping the bender differently, but this does give a baseline for comparison.     

TRANSLUCENT WHITE UMBRELLA  [ 1-1/3 Stop Loss ]    

My next modifier was a translucent white umbrella. Again, the zoom setting made minimal difference to the measured output, so I just report the 28 mm zoom results below.

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     28 mm    f/11    f/9      f/6.3     f/4.5    f/3.2   

As with the other front-attachable modifiers, the output was down about 4/3 stops from the 28 mm actual baseline.  

TWO SPEEDLITES w/TRANSLUCENT WHITE UMBRELLA [ 1 Stop Loss ]

My next setup was a surprise. It is exactly the same as the previous setup but I turned on both speedlites and fired them together. The surprise was that instead of gaining a full stop of light, I only seemed to gain about 1/3 of a stop.  This is about 1 full stop down from the single light 28 mm actual baseline.    

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     28 mm    f/13    f/10    f/7.1      f/5       f/4   

TWO SPEEDLITES w/SILVER REFLECTIVE UMBRELLA [ 1/3 to 2/3 Stop Loss ]

For my next setup, I simply turned the setup around and swapped a silver reflective umbrella for the white translucent one.  This produced the following results:  

     ZOOM     5 ft     7 ft     10 ft     14 ft     20 ft

     28 mm    f/13    f/11    f/9        f/6.3    f/4

     105 mm  f/11    f/9      f/7.1     f/5       f/3.2     

Interestingly, the results are similar to the white umbrella EXCEPT for a boost of about 1/3 to 2/3 of a stop in the 10 ft to 14 ft distance range. I am not sure if the shape of the umbrella tends to focus the light out in this range, but it acts like it and it was repeatable. The distance measured here is from the light stand - the light actually travels longer because it goes back to the umbrella before being reflected forward again. 

And also interestingly, zooming the speedlites to 105 mm actually produced less light in front.  I suspect this is because the speedlites themselves block any light reflected right back to them, and when tightly zoomed more light falls into this category. 

With both speedlites set to 28 mm zoom, there is a loss of 1/3 to 2/3 stop over bare speedlites in the 10 ft to 14 ft range. 

SOFTENING EXPERIMENTS   

Of course the power or intensity of the light is only one consideration in an actual photo session.  It is also important to know how directional or diffuse it is - at least relatively speaking.  In some cases where the gear must be carried, it is nice to know what the tradeoff is, if you opt for the more portable lighter setup?

For the second set of experiments, I took a simple self portrait.  I sat in a chair about 10 feet in front of a brick wall that was dimly lit with a couple of incandescent ceiling spots.  This was just enough to keep the background from going black, but was about 3 or more stops below the light I would meter on the subject. 

The lighting setup was placed on a stand about 7 feet high and about 9 feet from the subject and about 45 degrees off the camera-subject axis.  The camera was set for a shutter speed of 1/60, ISO=800, and an aperture of f/5.0.  For every setup, the speedlites were set to a zoom of 50 mm (except when using the wide panel) and the power was adjusted so that f/5.0 was measured at the subject location.

I purposely used no other light and room was fairly dark so that it was easier to tell what the modifier was doing to the primary light source.  As the subject, I tried to look at the same spot about halfway between the camera-subject axis and the light-subject axis.

Once I took the image, I brought it into Lightroom, converted to Greyscale and then measured the relative luminosity on the bright left cheek and the darker right cheek.  I then subtracted the two readings as a relative measure of the contrast / ratio between the directly lit side of the face and any feathering on the dark side.  The absolute numbers varied widely depending on how I selected my measurement points, but the relative order of softest setup to harshest remained fairly consistent.

TWO LITES w/WIDE PANELS  [45] (1/16 - 0.3) 

Somewhat of a surprise was that the "softest" score (45-46) went to the setup employing two speedlites.  Both were BARE except that I pulled out the wide panel diffuser on both.  The use of two lites also gave the "light" source an effectively wider profile.  Each of the two lites was set to a power of 1/16 - 0.3 .

TWO LITES - WHITE UMBRELLA [47-50] (1/16)

The second softest setup by this measure was afforded by another two speedlite setup. This time two lites with a White Translucent Umbrella. This produced a score of 47 on one measure and 50 on another, with both set to a power of 1/16. It produced this result:    

ROGUE FLASHBENDER (UP) [48-49] (1/8) 

This setup produced the best result using only one light.  In this case the speedlite was pointed at the white ceiling and had a large Rogue Flashbender attached an left relatively flat.  Power was set to 1/8 to achieve f/5.0 at the subject.  The result was:    

Obviously, we also pick up a bit more light on the upper forehead consistent with a lot of light coming off the ceiling.  

TWO LITES w/SILVER UMBRELLA [50-49]  (1/16)

The next setup achieved similar results, but was done using two speedlites again, but with a silver reflective umbrella.  Both lites were set to a power of 1/16 and produced this result:    

DOUG BOX LOCATION SOFTBOX [52-50]  (1/8 - 0.3)

Another very similar result was achieved using the Doug Box Location Softbox with one speedlite.  In this case the power was set to 1/8 - 0.3 and yielded a score in the 50 to 52 range.  This is the result:  

In this case the box was pointed directly at the subject.

DOUG BOX LOCATION SOFTBOX FEATHERED [50-53] (1/8 -0.3)

For this setup, I kept everything the same except that I pointed the box to the subject's right, so the light was feathered.  The result was very similar to previous setup.  

WIDE PANEL DIFFUSER [48-51]  (1/8)

Another setup producing similar results was a single speedlite with its Wide Panel Diffuser in place to give it an effective 14 mm zoom.  Again the power was set to 1/8 to achieve f/5.0 at the subject.  Interestingly this solution is by far the easiest and most portable of all the modifiers as it is built in. 

TWO SPEEDLITES BARE (50 mm ZOOM) [53-58] (1/64 - 0.7)

This setup consumed the least power - using a setting of only 1/64 - 0.7 to achieve f/5.0.  The setup was a little touchy on where I picked my measurement point, so result was a little less consistent than some.   

As you will see below, the harshest light came from using one speedlite bare, so the fact that we used two lights creating an effectively larger broader light source helped quite a bit.   

ULTIMATE LIGHT BOX  [55-57]  (1/16 + 0.7) 

The next setup employed one speedlite with a full Ultimate Light Box in place.  The power was set to 1/16 + 0.7 to achieve f/5.0 for the following result:    

PARTIAL ULTIMATE LIGHT BOX [58-59]  (1/32 + 0.3)  

The Ultimate Light Box can be disassembled and used in pieces.  It is made up of an inner diffuser around which is mounted another larger diffuser.  For this setup I removed the outer diffuser box and just used the inner little diffuser.  Interestingly while it used more power than a bare speedlite, it did not provide much softening benefit.   

ONE SPEEDLITE BARE (50 mm ZOOM) [59-59]  (1/32 - 0.7) 

In this last case, I used just one speedlite, zoomed to 50 mm and set to 1/32 - 0.7 power.  As you might expect this consistently produced the harshest light by the measurements in this experiment. 

In case you were lulled to sleep by the similar postings above and it is hard to compare all the way back to the first postings, I have reposted the TWO LITE w/WHITE UMBRELLA portrait from above to it is easy to compare to the SINGLE LITE BARE setup immediately above. 

Lastly, I repost for more direct comparison the result from the setup above that used only one speedlite, but the Wide Panel Diffuser was pulled out:    

CONCLUSIONS 

Maybe I should call it surprises rather than conclusions.  While we all know that broadening or diffusing the light source will soften the light, this attempt to quantify the benefit with different approaches produced some results I did not expect:

1.  I was surprised at how little benefit the partial Ultimate Light Box made.  In fact I probably would not bother with it, as the benefit is too small to justify lugging it around by itself.  If I could not use the whole thing, I would not use it simply to soften the light. 

2.  I was also surprised at how big a difference just using two speedlites mounted less than 12 inches apart with no modifiers made as compared to a single lite, everything else being equal. 

3.  I was very pleasantly surprised to see the huge impact of using the built-in Wide Panel Diffuser was.  In fact, using two lites with both utilizing their wide panel diffusers produced a result rivaling the softest by this test.  Given that this particular modifier is built-in to every speedlite and is never left home and requires lugging no extra gear, this is good to know.  Relatively speaking, it requires quite a bit of gear to beat it. 

4.  Another unexpected surprise was that I expected the Doug Box Location Softbox to be better than it was; I certainly did not expect a single speedlite with its Wide Panel Diffuser to be comparable.  Now there are times when the softbox is useful, but its limitations in terms of portability, and the inability to use additional speedlites (cannot mount more than one Canon 580 EX II) limit its flexibility.  Interestingly two speedlites with Wide Panels produced better results by this measure.  Were I to have measured more complicated setups where I had the freedom to feather the light more, the softbox probably would have done better, but in this simple test and where ambient and reflectors would contribute to an outdoor total lighting solution, I might question whether this gear was worth the space.

5. There is not a lot of difference in the loss associated with any of the box / umbrella modifiers. They all "cost" about 1-1/3 to 1-2/3 of a stop, so you basically waste about 2/3 of the available light you have to work with to use them. The Rogue FlashBender will cost another stop, halving the light again. This means it is probably best used as fill or to shape light in conjunction with a bounce off a larger surface.

6.  When using a softbox type modifier or translucent umbrella there is no benefit to changing the speedlite zoom.  It appears to be approximately the same as it would be at 28 mm.  The single exception is when using a silver reflective umbrella.  In this case manually zooming the lens to 105 mm, for example, actually reduces the forward light output, I suspect because it reflects more light back to the speedlite which blocks it from proceeding to the subject.    

7. I like the results of the translucent umbrella and find it more pleasing in this example than the silver reflective umbrella. Of course other tests have convinced me such umbrellas are not the best solution outdoors with any kind of wind. They too closely resemble a sail and have led to damaged equipment more than once. 

While most real portrait situations have more considerations than just one modifier on one light in a dark room, this experiment helped me understand in a more quantifiable way the lighting budget "cost" of each of these modifiers, and the relative softening benefit of each in at least one apples-to-apples case. In cases where I need a very portable and rapidly deployable solution, this does indicate a possible change in strategy over some of the things I have tried in the past - where I should be able to get a better benefit for less ergs of energy exerted.

May all your light be flattering.

Posted by Warren

Ayer Photography of Vermont                   


Posted by ayerphoto at 10:26 AM EDT
Updated: Thursday, 27 June 2013 5:08 PM EDT
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Wednesday, 19 June 2013
Focus On The Subject
Mood:  accident prone
Topic: Photography

Years ago I was photographing a running race and decided to try a feature on my new camera at that time I had not used previously.  It was a Canon 20D and I attempted to use the AI mode of Auto-Focus.  It was supposed to enable you to focus on a moving subject and the camera would predictably focus to get it right when you actually took the image.  The runner was coming up a hill, so they were not moving that fast and they were coming toward me at a steady pace.  It was a bright sunny day with lots of light, the runners were wearing colorful contrasty clothing and supposedly ideal for this focusing mode. 

I was under-whelmed.  My images were soft and no where near as crisp as I would have liked or expected.  In fact, I did better by pre-focusing at a point ahead of the runner and tripping the shutter at the moment they got there.  I tried again under a few different conditions, but never got what I thought were acceptable results - meaning that could not be bettered by alternate techniques.  As a result I never used the feature. 

As with most things with digital cameras, the technology has improved significantly since then.  With my current Canon EOS 1D mark IV I routinely use this mode for situations such as the bride coming down the aisle, etc.  It seemed time to test the limits and see just how much better it has gotten.  

I wanted to try to take some pictures that for me just could not be done any other way.  So, I decided to try a basketball game.  Unfortunately they did not have all the lights on and so photographically speaking it was very poorly lit.  This made the challenge even worse:  low light, subjects running quickly and unpredictably in a crowd, while sitting on a bouncy bleachers and using a long telephoto.    

While I would not enlarge any of them to wall poster size, I was impressed at how well the camera performed.  It also turns out that the focusing algorithm of the Canon 1D mark IV can be tweeked in custom settings for optimal performance - such as how fast it reacts to movement and weather the focus point expands to aid in tracking and how. 

Here was one of my first shots of a player running toward me, isolated from the other players. 

For the camera / photo enthusiasts, the shot specifics were:

Camera: Canon EOS 1D Mark IV

Lens:  Canon EF 70-200 mm f/2.8L IS USM at 195 mm at 20.6 meters 

Exposure: 1/640 at f/3.5, and ISO 5000

Settings: Manual Mode, Evaluative Metering, no flash

The compromise of course was trying to get enough depth of field and fast enough shutter speed to almost stop the subject.  Because the lighting was so poor and I didn't want to use a flash so as not to blind a player at an inopportune time, this necessitated using an ISO of 5000.  The resulting images were fairly noisy compared to what I normally like to see, but useable for this purpose. 

I then tried to get shots with more intense action.  At the shallow depth of field enabled by an aperture of f/3.5 and the speed of the subjects, keeping the focus point on the subject became THE CHALLENGE.  And it was not obvious that expanding the focus point would help because of the way the players were constantly crossing the camera view.  I gained a new appreciation for photographers of these kinds of sports just keeping focus on a subject.  I realize experience allows you to anticipate, but still it is not easy.  

Here is another one with a bit more action - similar settings.  

It gets more interesting when you try to shoot through a congested play.

Hmmm ... part kangaroo? 

Here is another one.   

Never had a chance!

But of course I really wanted to get one of those shots where the subject was really straining to do something heroic.  That I think takes a lot of experience to anticipate and know where to be when.  I did get this one where an attempt to block a shot appears to result in a blow to the jaw. 

After the basketball game, my next focus tracking experiment was butterflies.  For this one, I expanded the focus point, but even that was not enough.  I was unable to follow a butterfly in flight at close enough distance to be interesting and keep it in the frame, let alone with focus locked on.  I needed a bigger subject and slower relative motion so that I would not be the limitation. 

So, I tried seagulls.  There were several on the rocks circling and diving in slow irregular patterns.  With some practice and maybe a bit more tweaking of the AF parameters, I could get better, but I was happy to capture this fellow flying right at me.    

For the camera / photo enthusiasts, the shot specifics were:

Camera: Canon EOS 1D Mark IV

Lens: Canon EF 24-105mm f/4L USM at 105 mm at 6.5 meters

Exposure: 1/160 at f/22, and ISO 250

Settings: Manual Mode, Partial Metering, no flash

Some time ago I switched to back button focusing (using the AF-on button for focus lock rather than the shutter release button) and worked through changing my habits so I was locking focus and keeping stabilization on at the right times.  So, it felt good to dig into understanding the finer points of another mode of auto focusing.

After practicing on these very challenging moving subjects, the next time I try to capture the bride coming leisurely down the aisle, it will probably seem like a piece of cake! 

May you always stay focused on the right things!

Posted by Warren

Ayer Photography of Vermont         

For more information on Canon's AF system for the Canon EOS 1D mark IV and other cameras, see this article in their Digital Learning Center.  

If you are unfamiliar with "Back-Button AF" and would like more information, check out this link in the Canon Digital Learning Center.  

 


Posted by ayerphoto at 5:16 PM EDT
Updated: Wednesday, 19 June 2013 6:50 PM EDT
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Saturday, 1 June 2013
Photographing Family
Mood:  celebratory
Topic: Photography

Photographing family poses (no pun intended) its own challenges.  You may be the designated photographer by virtue of experience or equipment, but it is not the same as a paid engagement.  By definition it is a family event and not a photo session.  And while you understand that all they want is some good "snapshots," you would like to use some of your experience to make them better than "just snapshots."   

In doing family portraits at a wedding for example, most families are very cooperative in posing requests, since in our culture at least such photographs are part of the day.  And even if some of the participants are not interested, they know the bride is and so they make a reasonable effort to work with you. 

At a casual family affair, however, their patience for photographic perfection often comes in very small doses.  I was struck by this at a recent family event to celebrate a 65th wedding anniversary.  It was a small quiet event in keeping with the celebrants' wishes, but my wife did not want to miss a rare opportunity when most of the family was together to get some group portraits.  Everybody said, "sure, no problem!"  

But my wife had recently been watching some training videos on posing groups and thought it might be a good idea to employ some of their suggestions for helping people look their best.  Their reaction?   

You got it!  That was way too formal for them!  At that point we had the good sense not to suggest we set up lights and settled for a simple bounce flash.   

For the camera / photo enthusiasts, the shot specifics were:

Camera: Canon EOS 1D Mark IV

Lens: Canon EF 24-105mm f/4L USM at 35 mm (dist = 2.3m)

Exposure: 1/80 at f/6.3, and ISO 640

Settings: Manual Mode, Evaluative Metering, ETTL flash bounced off side wall    

While not the portrait I had in mind, it was a great "moment" and one that probably captures the joy of the day better than any formal shot could have done!  In families with a good sense of humor, it is best not to take yourself too seriously!

We did manage to get some more serious images, both of the anniversary celebrants and of their children.  

Quite an accomplishment to be married 65 years!   

And of course we managed a few candid shots along the way. 

and on the other side ...

More images can be found in one of our event galleries

May your years together with the ones you love be long, sweet and many!

Posted by Warren

     Ayer Photography of Vermont           


Posted by ayerphoto at 11:29 AM EDT
Updated: Saturday, 1 June 2013 1:24 PM EDT
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Saturday, 25 May 2013
One Off-Camera Flash Lighting
Mood:  quizzical
Topic: Photography

I am always looking for ideas for better lighting that are not only improvements in lighting, but are easily portable.  In some situations you have all the time in the world to lug gear to the shoot location, but in wedding photography, there are many situations where, if it isn't very portable, it is useless because you would never have time to go get it and set it up.     

I recently had occasion to watch a training video by Cliff Mautner on KelbyTraining.com titled, "One Flash Wedding Photography."  In some sense it was a variation on techniques also taught by Walter Van Dusen and Michael Greenberg.  Michael uses a flash attached to the camera by a cord and then one hands the camera one way and the flash the other.  He uses settings that are forgiving enough to make it work.  But, it is a young man's technique.  I found it physically exhausting with a Canon 1D series camera with heavy L-series lenses attached and therefore not practical for a wedding reception for me.  

Walter's technique used a video light on a pole operated by an assistant, often his daughter according to his blogs.  This has a number of advantages, but requires additional equipment with a specialized use. 

Cliff's version required one speedlight mounted on a monopod with a simple modifier.  It must be set up ahead of time, or operated by an assistant.  Like the others, you work out the settings for a specific distance and feathering arrangement and then simply tweek as you go.  This technique has the advantage of requiring very little additional equipment that we do not carry anyway, but does require new teamwork for a certain class of images, where the technique might be applicable. 

I wanted to write this blog to solidify in my own thinking: what I tried and why it works, so I would not forget, should I choose to try it later in a real situation.   

The objective is to use one speedlight to create directional lighting, very quickly in situations where you would not have time to set up something more complex.  Wedding receptions are notorious for creating such situations.  In fact Cliff's training example centered around the first dance, where the subject is moving and the ambient lighting is usually terrible to put it mildly.   

We experimented with some of the key aspects of the technique that might not seem intuitive, unless you are very familiar with your equipment and how it works.      

We tried it out in our living room on a dark and dreary day, which sort of simulates the reception with the lights turned down low.  Our one flash is mounted on a monopod tilted at about 60-degrees up from straight ahead.  We mounted an Ultimate Light Box to diffuse it, so the light to the subject is a combination of bounce off the ceiling and feather out the edge of the light box modifier.  We used Pocket Wizard Plus II and III transceivers and the speedlight was manually set to 1/4 power.  The speedlight on the monopod was then positioned about 12 feet from the subject.      

The camera / shot specifics were:

Camera: Canon EOS 1D Mark IV

Lens:  Canon EF 70-200 f/2.8L IS USM at 90 mm

Exposure: 1/40, at f/5.6, and ISO 640

Settings: Manual Mode, Evaluative Metering, Off-Camera Manual Flash    

Flash Stops The Action /  Motion

The first lesson we get out of this exercise is that the flash is "stopping the action or motion."  If we have read anything about modern flashes this is probably something we remember.  And we may have tried to take advantage of it once or twice and it may or may not have appeared to work.  Like most things, this truth has limitations - it is "true" and useful only under certain conditions, which you may or may not have fully explored. 

In this case you can see I violated one of the cardinal rules of photography.  My shutter speed was only 1/40 of a second, well under the recommended 1/90th dictated by the focal length of my telephoto zoom.  And it was still quite sharp - helped along by the fact that my lens had image stabilization and the fact that my dominant light source was my flash.  What constitutes "dominant" according to Cliff seems to be about 2 stops - meaning if the proper exposure for the light from the flash is about 2 stops (4X) or more brighter than the ambient then the very fast speed of the flash will in effect "stop" the action or motion.

While you may not think I pushed it too hard with the example above, I tried a couple of others and got similar good results (the samples below are straight out of the camera).     

This image was again taken with the same flash settings, same f/5.6 and same ISO=640.  The difference was the shutter speed was down to 1/25 and the focal length was up to 115 mm.  If we push it even further we get the following.   

Again straight out of the camera.  Basic settings the same, but the shutter speed was slowed again to 1/15 and the focal length was upped to 200 mm.  Again, the image was quite sharp in the focused details. 

But, it does have limits.  I found if I turned the image stabilization off, softness began to show up, and if I tried to slow down to 1/6 I was not steady enough to keep it tack sharp.  

ISO and Aperture Control Flash Exposure, Shutter Controls Ambient

This is another lesson we should know in theory, but we do not often exploit to control contrast.  And there are limits, but there is a useful range that can be exploited to craft the image to your liking.  

Cliff suggests in setting up the off camera flash that we meter the ambient and then set the ISO and aperture to be two stops under exposed for our chosen shutter speed.  Then we adjust our flash distance and power to provide the proper exposure on our subject for the chosen ISO and aperture (f/5.6 and ISO = 640 in our example).  This means our subject will be two stops brighter, where lit by the flash than where lit by the ambient.  Here is the first of a series of three images that demonstrate the differential control.  The first is our nominal image taken at 1/25, f/5.6, ISO = 640, focal length = 70 mm.   

 For the next image, we left everything exactly the same and only changed the shutter speed.  We increased it by two stops up to 1/100th. 

In this case the exposure of the subject is essentially the same, while the ambient is darker.  The contrast between something well lit by the flash to something lit primarily by ambient is increased.  

If I go the other way, and slow the shutter speed from 1/25 by approximately two stops to 1/6th we get this result.   

Here you can see the background lit primarily by the ambient is now significantly brighter, while the subject is still lit about as she was.

Not a perfect demonstration setup because there was some flat window lighting coming from behind the camera that did not extend all the way back to the brick.  But even so, I think the difference was enough to demonstrate the principle that to first order, you set the exposure on the subject with the flash, aperture and ISO, then tweek the shutter speed to get the preferred contrast to the background or ambient lit portion of the subject.  

Cliff is not alone in teaching this kind of approach. Doug Box, for example, uses a variation in his instructions for one-flash photography with his "Doug Box" softbox, as well as in his book, "Professional Secrets of Natural Light Portrait Photography."

There are many factors that go into making a great photograph. The trick sometimes is to have thorough understanding of what controls what, so that when you approach a new situation, you know how to improve it. For me, it is experiments like this that help to internalize the knowledge and move it from nice theory to practical techniques to improve real images.  

 Posted by Warren

Ayer Photography of Vermont


Posted by ayerphoto at 5:43 PM EDT
Updated: Sunday, 26 May 2013 3:31 PM EDT
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Wednesday, 8 May 2013
Wooded Reflections
Mood:  a-ok
Topic: Photography

Behind our house is a strip of woods that blocks the afternoon sun in the summer months and just provides some interesting textures in the winter.  The trees are tall and close together which means there are few low hanging branches.   

I have long thought that at the right time of day the textures of the wood and the mottled greens should make for a good photographic backdrop.  Results, however, have been mixed.  I have learned that white balance is tricky as it is easy to wind up with too much green reflected in the skin tones of your subject; and it is often so well shaded as to make the lighting mostly flat, or spotty - neither of which make for great portraits. 

So, it seemed like an experiment was in order to try some new lighting combinations to see if we could improve on whatever we had tried before.  Today's test was to use one off-camera flash mounted in a Doug Box softbox.  We metered the background average ambient and positioned the flash to provide about 1 to 2 stops brighter lighting on the subject.  I am a little vague on the ratio because the background is not consistent but actually has hot spots and dark shadows all at the same time.   

Our first results offered some promise, but the prevalence of dark shadows made some of the shadows on the dark side of the face a bit too dark for my taste.  So, since it was still morning and the sun was still reflecting some light in from the east especially off the lawn outside the wooded area we decided to add a gold reflector to pop a little bit of fill into the shadow side.  We found it was reflective enough to actually make it brighter than our main light, which we did not want.  But after tweeking the positioning we eventually arrived at a nice compromise - some fill to soften the shadow, but not so much as to compete with and flatten out the main light. 

Here is one of our results.  

The camera / shot specifics were:

Camera: Canon EOS 1D Mark IV     

Lens: Canon EF 24-70mm f/2.8 L USM at 66 mm (dist. = 2.6 m)    

Exposure: 1/100 at f/4.5, and ISO 200

Settings: Manual, Evaluative Metering

Lighting: Canon 580 EX II Speedlite off camera in softbox + reflector

While the hot spots from the distant clearing in the background might suggest otherwise, the background was darker than our subject for the most part.  We wondered then about the applicability of the same basic setup to the reverse - that is, where the backdrop was a lot brighter than the lighting at the subject position?

So, we basically turned around and shot into a more easterly direction where we saw a lot of very well lit lawn and other foliage in the morning sun.  While we had to stop down our exposure and up the power on our speedlite, we were able to produce similar results with a very different backdrop as you can see here.   

The camera / shot specifics in this case were:

Camera: Canon EOS 1D Mark IV     

Lens: Canon EF 24-70mm f/2.8 L USM at 70 mm (dist. = 2.6 m)    

Exposure: 1/250 at f/7.1, and ISO 200

Settings: Manual, Evaluative Metering

Lighting: Canon 580 EX II Speedlite off camera in softbox + reflector

Interestingly, since the light hitting the reflector was significantly brighter in this location, feathering it just right took a lot more care to find an acceptable compromise - it was easy to overwhelm the main light which we did not want to do.

So we wrote it up as a successful experiment in reflections in the woods.

Posted by Warren

Ayer Photography of Vermont              


Posted by ayerphoto at 4:26 PM EDT
Updated: Sunday, 26 May 2013 5:14 PM EDT
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Thursday, 8 November 2012
Tips For Buying A Used Lens
Mood:  quizzical
Topic: Photography

When I bought my first DSLR and a lens to go with it, my primary criteria were utility and affordability.  Since I could only afford one lens to start with I wanted it to be applicable to a wide range of photography situations and be within my affordable budget.  As digital cameras improved and my skills with them, upgrades soon were in order.  I purchased lenses that would allow me to photograph in situations where my first lens was wholefully inadequate and I would get the largest improvement in capability for a reasonable cost.   

Eventually when you have the range of wide angle to practical telephoto covered, you begin to notice the short comings in the lenses you purchased to start out.    

For me, the two that bugged me the most were the lack of clarity and lack of sealing characteristic of the less expensive lenses.  At one point finding dirt and dust invading the interior of lenses I used everyday caused me to vow to only buy professional level lenses.  These lenses usually have far superior weather sealing and it is rare to get dust and dirt inside the lens.  In fact I have never seen it on any of my L-series Canon lenses (of course I do not go out in a wind storm or ever set my camera down in a dusty environment to push my luck, either).    

Having bought my first few L-series lenses, I began to notice the significant inprovement in sharpness across the frame in some designs over their non-L counterparts.  This just reinforced my determination to stick to the pro-level lenses unless there was a significant reason to get a lens not available as an L.    

Once I made this jump, however, my ability to add lenses to my collection slowed down, as they were often significantly more expensive.  As a result when I had the opportunity to purchase a used L-series lens to fill a gap in my arsenal I wanted to consider it seriously.  In my case the lens was being offered by a friend, who had used it regularly for wedding photography.  

Since the whole reason to consider purchasing an L-series lens in the first place is function and quality of the resulting images, if it was not an improvement over what I already had, then it was not a good deal.  In a private sale you do not have the luxury of gettng a money back guarantee or any of the usual protections of dealing with a retail channel.   

So, the question comes up, how do you know a used lens is a good deal.   If a professional has used it, you have some confidence that it once was a good lens, but it has probably also been used extensively.  What do you look for?   

As I answered this question for myself, I thought others might benefit from what I found.    

I was fortunate in that my friend actually let me take the lens for a couple of days to put it through its paces.  I also found an article online at the Photography Talk forum that gave 12 Tips for Avoiding Buying a Lemon Lens on Craigslist.  So that was my starting point.  It was not a complete list for me, so I thought I would write my own rather than just post a link.         

 1.  Their first tip was simply a reminder that it is better to know from whom you purchase.  And even, then it is prudent to inspect what you are buying before you pay, to make sure it delivers on the promise that caused you to want the lens in the first place.  In my case the used purchase price for the L-series lens while a discount off a new L, was still significantly more than a comparable non-L lens.

2.  The second tip was to make sure the lens was compatible with your camera - make sure it has the correct mount for your camera and if you are planning to use it with extenders or other accessories, make sure of that compatibility.  In my case I had researched the specs of the particular model and already knew that it was compatible with my lens mount and my 1.4x tele-extender.  Once I had the actual unit in hand, I mounted it on my camera and verified that all the functions were working.  For example that autofocus, stabilization, etc. worked with the lens alone and with the extender, which in my case they did.  The next step was to assess how well they worked.     

3.  The third tip was to shoot a few frames and check the results on a computer, so you can really see detail subtleties.  The LCD on the back of the camera can tell you if there is anything grossly wrong, but not subtle quality issues.     

4.  The fourth tip was to inspect the lens construction.  The article suggested wrapping your hand around it.  It should feel solid and be tightly constructed and definitely not wobble in any way.  The exterior should be clean.  The focus ring should not rattle.  In all probability the rubber parts of the lens will have signs of wear, which is to be expected in a used lens, but should be cosmetic only and not degrade the functionality.    

5.  The fifth tip is to give the focus ring a complete turn be conscious of how smooth and easy it operates.  Do the same with the zoom control if it is a zoom lens.  They should turn smoothly through the entire range of settings and not hesitate or get stuck.  I also mounted the lens on my camera and proceeded to autofocus on a variety of subjects at varying distance in varying light and noticed how smoothly and quickly the lens responded.  I also tried it in extremely low light trying to force it to hunt for focus just to see how smoothly it responded.  I then put the camera in manual mode and set it to different aperature settings.  To see how the camera responds can be done by taking images and also my looking into the lens and pushing the DOF button on the camera that tells the lens to shut down to the desired setting.  You can see the blades moving - they should be very quick and smooth.   

6.  Next, they suggested inspecting the front element of the lens by tilting it at an angle so that a strong light can reflect from it.  This will reveal defects in the lens coating.  You should look for a consistent finish and no marks or scratches, swirls, or places where the coating as disappeared.  It is suggested that a few small specks are no big deal, but they are more leverage for paying less than asked.  In my case it was this inpection that revealed a couple of shallow scratches on the front element.  I agonized over how big a deal this was.  The price was lower than a current new lens, but would this be a deal breaker?  I went out and shot many images under lots of different lighting and varous distances and depth of field.  I then examined the images on my computer and searched the area that should be impacted by the scratches.  The net for me was that I could find no evidence of the scratches in any of my final images.  (After I bought the lens I also used it at a wedding the first weekend and could not find a trace of them on any of my images - and this represented my typical shooting conditions).  So, while these scratches "bothered me" and I wished they were not there, I could find no technical reason to reject the lens because of them. 

7.  The seventh tip is to then inspect the camera end of the lens.  They suggest that scratches are normal on the mount itself, but the rear element should be free of defects under reflected oblique light.  In my case the rear mount was in near new condition and the rear element was spotless, raising no concerns.     

8.  After inspecting the surface of the rear element, it is suggested that you open the aperature to the widest aperature and move the focus ring.  The glass should move in and out somewhere depending on its construction.  If there are no moving elements, then you are holding a "lemon" lens.  While this is listed as a separate tip, I would think it would have had trouble passing a focus test without any moving elements.    

9.  Now it is suggested that you switch to the smallest aperature.  When mounted to most DSLR's this may not actually do anything unless you push the DOF button.  In my case I put the camera in manual and pushed the DOF button and adjusted the aperature to varous values.  Looking into the lens you should see the aperature blades "pop" to the proper setting when you push the DOF button and then pop back when released.  Movement of the blades should be quick and smooth.  This is a good time to shine a light on the blades and make sure they open symmetrically and there are no marks or hesitations.  In my case one blade had a few very minor scratches but in all tests movement was smooth and exact.  

10.  The tenth tip is to open the aperature to its widest setting and shine a light into the lens.  You may spot some marks that look like spider webs.  This is probably fungus inside the lens and you do not want it.  They suggest that if you notice small dust particles, do not be concerned.  On this point I disagree.  Whether they will be a problem depends on where they are and they could move.  I have had lenses without good sealing that had wound up with particles on some internal elements and these were visible in the images it took.  In my evaluation of the L lens, it was clean.    

11.  The final inpection point suggeste is to view through the front of the lens and look at the aperature blades or diaphragm.  Check to see that they are clean and still have a matte finish.  If you see any shiy surfaces, these are likely to be a film of oil and are an indication that it is a lens you should avoid.    

12.  Inspecting a lens is time consuming, but taking your time to do it right is the only way to avoid buying a "lemon."  Remember that you are probably buying the lens because you want it to be an upgrade over what you already have.  It will not be an upgrade it if has some serious problems that degrade the images and you are better off saving for another lens.    

In may case, I have gotten a lot more experience with my lens than I had in the initial ispection.  I have found a softness in focus in the corners, for example.  The question was whether or not this is a fundamental characteristic of the lens.  I compared my resuts to some of the detailed reviews on imaging-resource.com and found that what I was seeing was close to what they measured on a brand new lens. 

A last issue with a used lens has to do with accessories.  If the lens is old enough, accessories may be difficult to get.  In my case the owners had lost the original tripod mount, but found a third party replacement which they gave me.  It basically will fit on the lens but will not rotate as it should.  I have checked on the Internet and found lots of others who have had this problem with these third party rings.  Unfortunately it seems to be impossible to get new ones from Canon anymore, so this is the best I can do for now. 

I did check compatibility of the lens with my existant 1.4X teleconverter.  It fit properly and both autofocus and image stabilization worked correctly.  

Image stabilization is hard to check.  You can tell if it works at all just by focusing on a distant object and engaging autofocus while hand held.  Without autofocus on, you will see the object move with you in the viewfinder, but should be stable when you engage autofocus.  So, you will know it is an improvement over no stabilization, but would require many test images to see if you got the typical improvement of a new lens. 

Hopefully this has been helpful if you are in the market for your first used lens.  

Posted by Warren

Ayer Photography of Vermont       

UPDATE # 1:  After using the lens for a while, I am still very happy with its optical performance, focusing, etc.  What I was very unhappy with is the cheap tripod mount that is non-canon hardware.  I had used it for what I thought was for an extreme test - that is with a 1.4x teleconverter in place and all went well enough.  The problem came later when during an engagement shoot I wanted to mount on a tripod without a converter so I could also adjust off-camera lights.  I could not get it on the tripod with a quick release plate.  The quick release lever hits the camera body and will not let the lens lower into place.  If the mount had allowed the lens to rotate as it was supposed to I could have rotated 90 degrees for more clearance, locked it into place and then rotated back and shot as I wanted.  Because I could not do this I had to mount the tripod back on the camera leaving the whole set up very unbalance and extremely front-heavy.  

I resolved to try another mount if I could find one and discovered almost accidentally that the Canon mount appears to be back in stock and have ordered one.  It is about 10X the price of the knock-off, but if it actually works, it will be worth it!            

UPDATE # 2:   Well the authentic Canon Tripod Mount B arrived today.  I slipped it on my lens, it went on smoothly and precisely, and it rotates smoothly without catching or wiggling.  I mounted the lens on my Canon 1D mark IV and lo and behold I was able to mount the camera and lens onto the tripod, which I was unable to do with the knock-off!  Of all the photographic gear I would have thought a tripod mount would have been one of the easiest pieces to copy, but apparently it is harder than it looks.  Simply because it works, the authentic version is worth the cost - the knock-off has been consigned to the trash.        


Posted by ayerphoto at 4:50 PM EST
Updated: Thursday, 30 May 2013 8:09 PM EDT
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Saturday, 11 February 2012
12 Elements Of A Merit Photograph
Mood:  sharp
Topic: Photography

The season of photographic print competitions will soon be upon us.  In fact the annual print competition of the Vermont Professional Photographers is now only a few weeks away.  Ugh!  I still have to do some final edits and get my entries printed and mounted for exhibition.  I always plan to start early, but somehow the time seems to slip away; and before I know it, I am facing the possibility of needing expedited shipping to get them back in time.   

Within the various affiliates of the Professional Photographers of America, you will always hear one common refrain - entering print competitions will make you a better photographer.  Sure, there will always be a photograph here and there that you may have thought should score better than it did - and with some justification, since it is a subjective judgment after all!  But there will be many more that you will agree could have been better - and picked up a few clues as to ways to do just that.  Sometimes the clues relate to how to take the image differently, and other times it is how to post process it for better effect.  At the very least, when you look through the lens to take a new picture after having been through print competition, you do tend to "see" a little differently, a little more critically, a little more aware of the light, and a little more aware of what translates to a print better.    

It is always helpful, as I contemplate which images to enter, to go back and remind myself of what the judges will look for.  It is not necessarily the same things with the same priorities that a wedding customer would look for, but they do have significant overlap.   

Within the Professional Photographers of America affiliates and their various print competitions, there are 12 elements that the judges look for in an image to determine whether it rises to the level of being "merit worthy."  That is, worthy of recognition at a national level.      

The twelve elements are subjective and you will rarely find even five judges with similar backgrounds who will give the same score.  In observing a few competitions, there are always a handful of images that will garner a 15 or more point spread from highest to lowest individual judge's score.  For most prints, however, while they will rarely agree on an exact score, there is usually a pretty strong consensus for whether a print is a merit contender or not.  Interestingly, it seems that if a print is a good example of most of the 12 elements, it will score high.  If it seems to miss the mark on most elements, it will score low.  It is usually where the image scores high on only one or two elements, but low on others that the judges will be widely split - depending on how they personally tend to prioritize the different elements.  

The twelve elements have been defined and used within PPA to describe what is necessary for the success of an art piece or image.  While other organizations will have their own lexicon, you usually find they are looking for the same things - just defining them a bit differently.  The presumption is that any image, art piece or photograph will reveal some measure of all twelve elements, while a visually superior example will reveal obvious consideration of each one.  The elements as defined within PPA are:

The Photographic Exhibitions Committee (PEC) of PPA uses the 12 elements above as the “gold standard” to define a merit image.  They believe that the use of these 12 elements connects the modern practice of photography and its photographers to the historical practice of photography begun nearly two centuries ago.

Happy shooting!     

Posted by Warren

Ayer Photography of Vermont              

one of our galleries ...

 


Posted by ayerphoto at 6:34 PM EST
Updated: Saturday, 18 February 2012 10:38 AM EST
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Sunday, 1 May 2011
Ansel Adams' Zone System
Mood:  a-ok
Topic: Photography

As part of our own growth as artists we are constantly trying to train ourselves to "see the light" and more, get the camera to capture what we "see."  One starting point in any such process is the ...   

Zone System

From Wikipedia, the free encyclopedia

The Zone System is a photographic technique for determining optimal film exposure and development, formulated by Ansel Adams and Fred Archer in 1939–1940.[1] The technique is based on the late 19th century sensitometry studies of Hurter and Driffield. The Zone System provides photographers with a systematic method of precisely defining the relationship between the way they visualize the photographic subject and the final results. Although it originated with black and white sheet film, the Zone System is also applicable to roll film, both black and white and color, negative and reversal, and to digital photography.

Principles

Visualization

An expressive image involves the arrangement and rendering of various scene elements according to photographer’s desire. Achieving the desired image involves image management (placement of the camera, choice of lens, and possibly the use of camera movements) and control of image values. The Zone System is concerned with control of image values, ensuring that light and dark values are rendered as desired. Anticipation of the final result before making the exposure is known as visualization.

Exposure metering

Almost any scene of photographic interest contains elements of different luminance; consequently, the “exposure” actually is many different exposures. The exposure time is the same for all elements, but the image illuminance varies with the luminance of each subject element.

Exposure is often determined using a reflected-light[2] exposure meter. The earliest meters measured overall average luminance; meter calibration was established to give satisfactory exposures for typical outdoor scenes. However, if the part of a scene that is metered includes large areas of unusually high or low reflectance, or unusually large areas of highlight or shadow, the “effective” average reflectance[3] may differ substantially from that of a “typical” scene, and the rendering may not be as desired.

An averaging meter cannot distinguish between a subject of uniform luminance and one that consists of light and dark elements. When exposure is determined from average luminance measurements, the exposure of any given scene element depends on the relationship of its reflectance to the effective average reflectance. For example, a dark object of 4% reflectance would be given a different exposure in a scene of 20% effective average reflectance than it would be given in a scene of 12% reflectance. In a sunlit outdoor scene, the exposure for the dark object would also depend on whether the object was in sunlight or shade. Depending on the scene and the photographer’s objective, any of the previous exposures might be acceptable. However, in some situations, the photographer might wish to specifically control the rendering of the dark object; with overall average metering, this is difficult if not impossible. When it is important to control the rendering of specific scene elements, alternative metering techniques may be required.

It is possible to make a meter reading of an individual scene element, but the exposure indicated by the meter will render that element as a medium gray; in the case of a dark object, that result is usually not what is desired. Even when metering individual scene elements, some adjustment of the indicated exposure is often needed if the metered scene element is to be rendered as visualized.

Exposure zones

In the Zone System, measurements are made of individual scene elements, and exposure is adjusted based on the photographer’s knowledge of what is being metered: a photographer knows the difference between freshly fallen snow and a black horse, while a meter does not. Much has been written on the Zone System, but the concept is very simple—render light subjects as light, and dark subjects as dark, according to the photographer’s visualization. The Zone System assigns numbers from 0 through 10[4] to different brightness values, with 0 representing black, 5 middle gray, and 10 pure white; these values are known as zones. To make zones easily distinguishable from other quantities, Adams and Archer used Roman rather than Arabic numerals. Strictly speaking, zones refer to exposure,[5] with a Zone V exposure (the meter indication) resulting in a mid-tone rendering in the final image. Each zone differs from the preceding or following zone by a factor of two, so that a Zone I exposure is twice that of Zone 0, and so forth. A one-zone change is equal to one stop,[6] corresponding to standard aperture and shutter controls on a camera. Evaluating a scene is particularly easy with a meter that indicates in exposure value (EV), because a change of one EV is equal to a change of one zone.

Many small- and medium-format cameras include provision for exposure compensation; this feature works well with the Zone System, especially if the camera includes spot metering, but obtaining proper results requires careful metering of individual scene elements and making appropriate adjustments.

Zones, the physical world and the print

The relationship between the physical scene and the print is established by characteristics of the negative and the print. Exposure and development of the negative are usually determined so that a properly exposed negative will yield an acceptable print on a specific photographic paper.

Although zones directly relate to exposure, visualization relates to the final result. A black and white photographic print represents the visual world as a series of tones ranging from black to white. Imagine all of the tonal values that can appear in a print, represented as a continuous gradation from black to white:

 

 

 
Full Tonal Gradation

From this starting point, zones are formed by:

 

 

 
Eleven-Step Gradation
Note: You may need to adjust the brightness and contrast of your monitor to see the gradations at the dark and light end of the scales.

Eleven Symbolic Tones
           

The Zone Scale
0IIIIIIIVVVIVIIVIIIIXX

Zones as tone and texture

Adams (1981, 52) distinguished among three different exposure scales for the negative:

He noted that negatives can record detail through Zone XII and even higher, but that bringing this information within the exposure scale of the print is extremely difficult with normal processing.

Adams (1981, 60) described the zone scale and its relationship to typical scene elements:[7]

ZoneDescription
0Pure black
INear black, with slight tonality but no texture
IITextured black; the darkest part of the image in which slight detail is recorded
IIIAverage dark materials and low values showing adequate texture
IVAverage dark foliage, dark stone, or landscape shadows
VMiddle gray: clear north sky; dark skin, average weathered wood
VIAverage Caucasian skin; light stone; shadows on snow in sunlit landscapes
VIIVery light skin; shadows in snow with acute side lighting
VIIILightest tone with texture: textured snow
IXSlight tone without texture; glaring snow
XPure white: light sources and specular reflections

For cinematography, in general, parts of the scene falling in Zone III will have textured black, and objects on Zone VII will have textured white. In other words, if the text on a piece of white paper is to be readable, light and expose the white so that it falls on Zone VII. This is a general rule of thumb. Some film stocks have steeper curves than others, and the cinematographer needs to know how each one handles all shades of black-to-white.

Technique

Effective film speed

The ISO standard for black and white negative film, ISO 6:1993, specifies development criteria that may differ from those used in practical photography (previous standards, such as ANSI PH2.5-1979, also specified chemistry and development technique). Consequently, the Zone System practitioner often must determine the speed for a particular combination of film, developer, and enlarger type; the speed determination is commonly based on Zone I. Although the method for determining speed for the Zone System is conceptually similar to the ISO method for determining speed, the Zone System speed is an effective speed[8] rather than an ISO speed.

Exposure

A dark surface under a bright light can reflect the same amount of light as a light surface under dim light. The human eye would perceive the two as being very different but a light meter would measure only the amount of light reflected, and its recommended exposure would render either as Zone V. The Zone System provides a straightforward method for rendering these objects as the photographer desires. The key element in the scene is identified, and that element is placed on the desired zone; the other elements in the scene then fall where they may. With negative film, exposure often favors shadow detail; the procedure then is to

  1. Visualize the darkest area of the subject in which detail is required, and place it on Zone III. The exposure for Zone III is important, because if the exposure is insufficient, the image may not have satisfactory shadow detail. If the shadow detail is not recorded at the time of exposure, nothing can be done to add it later.
  2. Carefully meter the area visualized as Zone III and note the meter’s recommended exposure (the meter gives a Zone V exposure).
  3. Adjust the recommended exposure so that the area is placed on Zone III rather than Zone V. To do this, use an exposure two stops less than the meter’s recommendation.

Development

For every combination of film, developer, and paper there is a “normal” development time that will allow a properly exposed negative to give a reasonable print. In many cases, this means that values in the print will display as recorded (e.g., Zone V as Zone V, Zone VI as Zone VI, and so on). In general, optimal negative development will be different for every type and grade of paper.

It often is desirable for a print to exhibit a full range of tonal values; this may not be possible for a low-contrast scene if the negative is given normal development. However, the development can be increased to increase the negative contrast so that the full range of tones is available. This technique is known as expansion, and the development usually referred to as “plus” or “N+”. Criteria for plus development vary among different photographers; Adams used it to raise a Zone VII placement to Zone VIII in the print, and referred to it as “N + 1” development.

Conversely, if the negative for a high-contrast scene is given normal development, desired detail may be lost in either shadow or highlight areas, and the result may appear harsh. However, development can be reduced so that a scene element placed on Zone IX is rendered as Zone VIII in the print; this technique is known as contraction, and the development usually referred to as “minus” or “N−”. When the resulting change is one zone, it is usually called “N − 1” development.

It sometimes is possible to make greater adjustments, using “N + 2” or “N − 2” development, and occasionally even beyond.

Development has the greatest effect on dense areas of the negative, so that the high values can be adjusted with minimal effect on the low values. The effect of expansion or contraction gradually decreases with tones darker than Zone VIII (or whatever value is used for control of high values).

Specific times for N+ or N− developments are determined either from systematic tests, or from development tables provided by certain Zone System books.

Additional darkroom processes

Adams generally used selenium toning when processing prints. Selenium toner acts as a preservative and can alter the color of a print, but Adams used it subtly, primarily because it can add almost a full zone to the tonal range of the final print, producing richer dark tones that still hold shadow detail. His book The Print described using the techniques of dodging and burning to selectively darken or lighten areas of the final print.

The Zone System requires that every variable in photography, from exposure to darkroom production of the print, be calibrated and controlled. The print is the last link in a chain of events, no less important to the Zone System than exposure and development of the film. With practice, the photographer visualizes the final print before the shutter is released.

Application to other media

Roll film

Unlike sheet film, in which each negative can be individually developed, an entire roll must be given the same development, so that N+ and N− development are normally unavailable.[9] The key element in the scene is placed on the desired zone, and the rest of the scene falls where it will. Some contrast control is still available with the use of different paper grades. Adams (1981, 93–95) described use of the Zone System with roll film. In most cases, he recommended N − 1 development when a single roll was to be exposed under conditions of varying contrast, so that exposure could be sufficient to give adequate shadow detail but avoid excessive density and grain build-up in the highlights.

Color film

Because of color shifts, color film usually does not lend itself to variations in development time. Use of the Zone System with color film is similar to that with black and white roll film, except that the exposure range is somewhat less, so that there are fewer zones between black and white. The exposure scale of color reversal film is less than that of color negative film, and the procedure for exposure usually is different, favoring highlights rather than shadows; the shadow values then fall where they will. Whatever the exposure range, the meter indication results in a Zone V placement. Adams (1981, 95–97) described the application to color film, both negative and reversal.

Digital photography

The Zone System can be used in digital photography just as in film photography; Adams (1981, xiii) himself anticipated the digital image. As with color reversal film, the normal procedure is to expose for the highlights and process for the shadows.

Until recently, digital sensors had a much narrower dynamic range than color film, which, in turn, has less range than monochrome film. But an increasing number of digital cameras have wider dynamic ranges. One of the first was Fujifilm’s FinePix S3 Pro digital SLR, which has their proprietary “Super CCD SR sensor” specifically developed to overcome the issue of limited dynamic range, using interstitial low-sensitivity photosites (pixels) to capture highlight details.[citation needed] The CCD is thus able to expose at both low and high sensitivities within one shot by assigning a honeycomb of pixels to different intensities of light.

Greater scene contrast can be accommodated by making one or more exposures of the same scene using different exposure settings and then combining those images. It often suffices to make two exposures, one for the shadows, and one for the highlights; the images are then overlapped and blended appropriately[1], so that the resulting composite represents a wider range of colors and tones. Combining images is often easier if the image-editing software includes features, such as the automatic layer alignment in Adobe Photoshop CS3, that assist precise registration of multiple images. Even greater scene contrast can be handled by using more than two exposures and combining with a feature such as Merge to HDR in Photoshop CS2 and later.

The tonal range of the final image depends on the characteristics of the display medium. Monitor contrast can vary significantly, depending on the type (CRT, LCD, etc.), model, and calibration (or lack thereof). A computer printer’s tonal output depends on the number of inks used and the paper on which it is printed. Similarly, the density range of a traditional photographic print depends on the processes used as well as the paper characteristics.

Histograms

Most high-end digital cameras allow viewing a histogram of the tonal distribution of the captured image. This histogram, which shows the concentration of tones, running from dark on the left to light on the right, can be used to judge whether a full tonal range has been captured, or whether the exposure should be adjusted, such as by changing the exposure time, lens aperture, or ISO speed, to ensure a tonally rich starting image.[10]

Misconceptions

The Zone System gained an early reputation for being complex, difficult to understand, and impractical to apply to real-life shooting situations and equipment. Much of the difficulty may have resulted from Adams’s early books, which he wrote without the assistance of a professional editor; he later conceded (Adams 1985, 325) that this was a mistake. Picker (1974) provided a concise and simple treatment that helped demystify the process. Adams’s later Photography Series published in the early 1980s (and written with the assistance of Robert Baker) also proved far more comprehensible to the average photographer.

The Zone System has often been thought to apply only to certain materials, such as black-and-white sheet film and black-and-white photographic prints. Adams (1981, xii) suggested that when new materials become available, the Zone System is adapted rather than discarded. He anticipated the digital age, stating

I believe the electronic image will be the next major advance. Such systems will have their own inherent and inescapable structural characteristics, and the artist and functional practitioner will again strive to comprehend and control them.

Yet another misconception is that the Zone System emphasizes technique at the expense of creativity. Some practitioners have treated the Zone System as if it were an end in itself, but Adams made it clear that the Zone System was an enabling technique rather than the ultimate objective.          


Posted by ayerphoto at 2:33 PM EDT
Updated: Sunday, 1 May 2011 3:08 PM EDT
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