Experiments in Tilt-shift Specimen Photography

Once the amateur’s naive approach and humble willingness to learn fades away, the creative spirit of good photography dies with it. Every professional should remain always in his heart an amateur. –Alfred Eisenstaedt

Dikelokephalina sp., Ordovician Period, China
Dikelokephalina sp., “relict capstone,”Ordovician Period, Dra Valley, Morocco. This is a big bug! By using a tilt-shift lens it was possible to keep the entire specimen in focus from cephalon to pygidium down the long axis of the body. All specimen images in this post were taken with a Canon EOS 7DII/90mm f/2.8 TS-E (tilt-shift lens). Natural light. Trilobite about 23 cm long.

As a student of photography I am always struck by the relentless, compromise-demanding nature of the art. All the important variables of photography are always working against each other. Decreasing aperture (higher f-stop) means greater depth of field but demands slower shutter speed or higher ISO. Slower shutter speed threatens motion blur, and higher ISO degrades image quality. The fastest, sharpest lenses are primes, which are big, heavy, clunky and monstrously expensive—leaving you less money to spend on other equipment! The list of compromises goes on and on.

Large unidentified as aphid, Ordovician Period, Morocco
Another big bug! Large unidentified asaphid, “Ordovician deposits of Tassmamte,” Tanssikhte, near Zagora, Morocco. Despite being close to the specimen (and at a funny angle), I was again able to keep the whole specimen in focus simultaneously by using a tilt-shift lens. Natural light. Specimen is about 14.5 cm long. 

Macrophotography and close-up photography, my favorite areas of photography after super telephoto work, are plagued by shallow depth of field. Depth of field in a standard lens is a function of three independent variables: aperture, focal length, and object distance. In macrophotography (or just being unusually close to the subject as in close up photography), the object distance is very small and so is the depth of field. To compensate for this, the photographer typically shoots at high f-stops, which in turn requires brilliant illumination or high ISO. Very high ISO or f-stops degrade image quality due to noise or diffraction, respectively.

But are there ways to cheat the laws of physics and increase depth of field? As it turns out, there are two ways (sort of—but there is payback in other areas): image stacking (not discussed here) and the Scheimpfluge principle. The latter is the physical basis of tilt-shift lenses. Tilt-shift lenses can shift the lens parallel to the focal plane (sensor) and tilt the optic axis of the lens, also relative to the sensor. These changes, alone or in combination, can produce a number of special effects. Readers unfamiliar with tilt-shift photography who have watched the television series Wallander may have wondered what the heck was going on!

Ogyginus corndensis, Ordovician Period, Builth-Wells, Powys, Wales, United Kingdom
Ogyginus corndensis, Ordovician Period, Builth-Wells, Powys, Wales, United Kingdom. For flat specimens, un-tilted tilt-shift lenses work just like a typical high-quality manual focus prime. Artificial light. Trilobite is 10.8 cm long. 

But the unique capabilities of tilt-shift lenses come at a cost, and are primarily of three kinds. First, tilt-shift lenses are premium quality professional lenses with price tags to match. My Canon 90mm f/2.8 TS-E is beautifully made engineering marvel. It feels more like a Leica or Rollei lens in the hands than the typical consumer-grade lens. Second, tilt-shift lenses are all manual. There is no autofocus. Third, tilt-shift lenses are very awkward to use. And, and this is a huge “and” in a practical sense, the increase in depth of field only occurs in the direction of tilt. Be ready to work for the shot.

Trumpet vine flower, Houston, Texas
Trumpet Vine Flower (Campsis radicans), Houston, Texas. This hummingbird nectar flower is hard to photograph because of its tubular, three-dimensional shape. Natural light. Flower is about 8 cm long.

My initial interest in tilt-shift began with being in the field tying to capture images of bird food-plant flowers for my digital bird photography website twoshutterbirds.com. It is often difficult to keep large, three-dimensional flowers completely in focus, and the lens I usually use for this application (Canon 100mm f/2.8L IS Macro) sometimes doesn’t do the job well.

Although tilt-shift lenses are expensive and a pain to use, they definitely have their place in a natural history photographer’s bag of tricks. Now it’s just finding the time to practice!

Canon gear
Digital 35mm Canon gear used for specimen photography: 100mm Macro (left), 7D DSLR (center), and 90mm TS-E (tilt-shift) with tilt and shift positions to their maxima.

©2016 Christopher R. Cunningham. All rights reserved. No text or images may be duplicated or distributed without permission.