February 27, 2013 | 3
Why is this beetle so crisp?
The clarity results from the image being not a single photograph but a composite. I took 50 exposures at different focal depths and merged them in a file sharp enough to cut diamonds.
This extra-clean look is increasingly common, and for a reason. Digital cameras and focus-stacking software are now affordable enough that “stacking” as a genre is positively thriving. Check out Flickr’s many groups devoted to the technique.
Since the method creates optically impossible images- no lens can produce a sharp image over an extended focal plane- stacks exude a surreal quality. An experienced eye can pick them, as most stacks transition from sharply focused to completely blurry with little subtlety. The in-focus bits are insanely crisp, and the out-of-focus bits are butter creamy.
I have been experimenting with disguising the telltale focus boundary. Since the point of stacking is to increase sharpness, blurring over the stack’s focused parts would be counterproductive. Instead, I settled on boosting background detail the old-fashioned way.
Once I had taken all the exposures to be included in the regular stack, without moving the camera or the beetle, I stopped the lens down, boosted flash power to compensate, and took one more photograph. This final capture left a similar but softer exposure with more native depth of field:
When the high DOF image is added to the stack as background, the image acquires a more realistic aspect while retaining its Whiz-Bang stack sharpness. Compare a stack with an additional small-aperture background file (top) to a stack without one (bottom):
The improved image is still the result of severe digital manipulation, but it doesn’t look as much like it.
To purchase a print of the weevil: http://bit.ly/WrVlmp