I get a lot of questions about doing closeup and macro studio photography with large format camera systems so I decided to write this article and walk you through a typical process. First, I went down to my local florist and picked up some large white Calla Lilies that I thought would make interesting subjects. For this project I decided to use my 8×10 large format camera with the Fuji 300mm lens and Tri-X 320 film. My Tri-X 320 sheet film is rated at EI 250 based on my testing procedures. My normal development time in D-76 1+ 1 is 8 1/2 minutes. I use the 300mm lens on the 8×10 because this is the standard lens for 8×10 and it makes for great closeup and macro work. I have over 800mm of bellows draw on my camera so I can go up to 2+ on my magnification ratio if I want. I also use a +2 diopter for super macro work.
Setup and Artistic Choices
After looking at the lilies I decided to take advantage of the beautiful white flowers and use a black background to add more drama and contrast to the scene. Then I decided to use a tall rectangular vase because it felt modern and contemporary to me. I thought the tall white Calla Lilies looked sophisticated so I wanted to take the scene in that direction. If I had used a vase with softer or more round lines it would have produced a much different result.
I used natural light from a window on the right side of the flowers to hopefully allow the translucent flowers to radiate as well as create a natural shadow from right to left. For this particular scene I had limited space between the background and the subject so I had to make a decision what zone to place the background on vs. the white portion of the flowers. I use the Zone system in my black and white fine art photography so my metering, development and printing is based on this system.
With large format you have to account for your bellows extension because your film gets further away from your lens and it needs more light to properly expose the film. This is commonly referred to as bellows factor. There are a number of ways to approach this but I have a method that I have been using for a long time that is very accurate. In my case this time I was using a 300mm lens and had 400mm of bellows extension. I simply take a soft tape measure and measure the distance between the lens and film back. I divide the bellows extension (400) by the lens length (300) and square that to get the bellows factor (BF). The calculation is as follows: (400/300)2. In this case my BF was 1.77. In order to get the amount of exposure compensation I need to perform another calculation using the log() function. This may seem complicated but it really isn’t and is actually very quick. I take the log() of my BF log(1.77) and divide by a log() of 2 log(2) and I get my exposure compensation. The calculation is as follows: log(1.77)/log(2) = .82 which is a little over 2/3rd of a stop. Two-thirds exactly would have been .75. In this specific case since I didn’t have a full stop of exposure comp I decide to open up the aperture 2/3 stop from f/45 to f/32 1/3. You can probably figure out that for a BF of 2 you need 1 stop of exposure compensation or double the exposure time. For 1 stop you could open your aperture up one stop of double your exposure time.
Next, since I am using Tri-X I have to factor in reciprocity failure and add adjust my exposure time. The baseline recommendations for reciprocity corrections can be found in the Kodak datasheet for Tri-X. Over time I have built my own tables based on experience starting with the Kodak guidelines. You need to calculate your total exposure time including reciprocity only after all corrections are made (e.g., bellows factor, filters, etc). My metered exposure for the first photo was 2 seconds and for reciprocity I had to add three seconds for a total of 5 seconds. For the second exposure my metered exposure was 8 seconds and my reciprocity correction was 29 seconds for a total exposure of 37 seconds. With reciprocity you also have to reduce development time based on the degree of failure. For the first exposure I reduced my normal (N) development time by 10% and the second 15%.
In this first photograph I metered the background for Zone 0 which is -5 stops of exposure compensation from Zone V. If you are not aware of it your meter measures your scene at Zone 5 (18% gray) by default. If I had left my meter as set without dialing in -5 stops of compensation the background would have been neutral gray and that was not what I wanted. This is mainly because of the short distance between the subject and background. However, I was worried about my whites and where they would fall based on making the decision on placing the background on Zone 0 (pure black). My background was pure black as expected on the negative and my white and mid-tones were probably about a stop below where I would have intentionally placed them.
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For the second photograph I went the other direction and metered the white part of the Lily and placed it on Zone VII which is +2 stops of exposure compensation and let the shadows fall where they wanted. As you probably expected I got better whites and mid-tones and my background showed texture and detail and was not exposed properly.
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You might be asking yourself what the solution is? There are a number of options that I could have pursued depending on my workflow and local variables. If I were scanning and printing digitally either of the two exposures would produce a professional quality print because of the power of Photoshop and the use of layers. If I had to pick one exposure over the other I would probably go with the second exposure because it had better detail and I could always burn the background to be black as intended or layer in mid-tones and shadows. If I were in the darkroom I would also probably go with the second negative and start with a number 2 VC filter and find the proper exposure for the whites in my flowers and then deal with the shadow detail and background my changing my VC filters until they looked right. More or less an optical approach to the Photoshop method.
Based on my above session I made some adjustments and took a new exposure early the next day. I moved the flowers about eight feet from the background and leveraged the morning sun coming through some blinds. By moving the flowers further away from the background I used the principle of light falling off and being able to get the black background without having to meter for the background at -5 stops (zone 0) and then deal with the flat mid-tones. If you compare this to the first two exposures above you will see a significant difference. There are no right or wrong answers in art, just differences. I wanted to use the blinds to create shadows across the vase and flowers and still hold good highlights and shadow detail.
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