Today’s image provides a pleasant counterpart to yesterday’s mild disappointment. I have never worked with a macro lens before, and I was quite pleased with the results I achieved in my first effort. I am far from knowing what I am doing, and some of the results I achieved were largely accidental I think, but that is no reason not to be pleased.
This is a peony in my backyard. I pulled back a bit from the really tight shots I had been getting to capture nearly the entire flower here. Normally you would have to carefully set up your strobes to turn your background black, but this happened naturally. This plant was in the shade when I first started working, but when I was nearly done the flowers on the top of the plant were just getting kissed by a mere hint of sunlight. That was apparently enough to create this effect, as the camera was metered on the sunlight and everything else was underexposed. I used very minor tweaks in Aperture to bring it to full black.
One thing I had not anticipated was the extremely narrow depth of field (DOF) in most macro photography. I know that depth of field is a physics problem based on three variables:
the aperture opening – wider means less depth
the length of the lens – longer means less depth
the distance from subject – closer means less depth.
Obviously for macro photography the last factor will always tend towards a narrow depth of field, but without having consulted a DOF calculator, I did not realize that it overwhelms the other two factors. Even closed down to f/32, I was getting only about 2.25 inches of focal depth here, which does not cover an entire flower at all. In addition, I noticed something that is sort of obvious but that I had not previously though of consciously: the two factors of lens length and distance from subject cancel each other out for any given framing. For example, I was using a 200mm macro lens, and this shot was taken about 3.9 feet from the subject. If I used a 50mm macro lens, I would have to be shooting about a foot from the subject to get the same size and framing.* If you consult a DOF calculator, you will find that 200mm/3.9ft and 50mm/1 ft yield very similar results at the same apertures.
In the shots where I was even more tightly focused than you see here, the working depth of field was really just a sliver of an inch, creating challenges for macro work that I had not really anticipated. But as I said, I am very pleased with this result, and with some others I managed to capture yesterday.
* This image also includes a modest crop that affects the image but not the analysis above.