In a comment on a Fossil of the Week post last month, Wooster Geologist Alumnus Dr. Bill Reinthal suggested I describe the processes I use to create images of rocks and fossils for this blog, publications and other outlets. This is a good idea because I can produce an outline of our macrophotography techniques for students and others to use as a reference. My only caveat is that I’m not a professional photographer by any means — I’m a scientist who does a lot of photography, trying to retain whatever useful ideas I’ve stumbled across. Like Bill, I’m still building on skills we learned in the Junior Independent Study Geologic Methods course during the last century! I also want to point out that all our departmental faculty and staff do photography and do it well. The following techniques are from my personal perspectives and experiences.
The image above is typical of my lab photography. It is a limestone bedding plane showing trace fossils in convex hyporelief (thus the sole of the bed; the bed is positioned upside-down). This rock is from the Eagle Mountain Ranch exposure of the Middle Jurassic Carmel Formation in southwest Utah, collected during our epic, star-crossed March 2020 expedition. Note the deep black background that provides the ultimate contrast with the edges of the slab. The rock appears to be floating in space with no distractions around it. The dominant light is coming from the upper left, following paleontological tradition for consistency. The yellow scale was added to the image later “in post” as the pros say.
This is the copy stand arranged to take the top image, minus the camera. I believe the four large lights go back at least to the 1970s, and the platform that holds the camera dates to before World War II! The components — A indicates the four main light bulbs (daylight color temperatures); only the back left one is on to produce the required upper-left dominant light source. B is a fiber-optic gooseneck spotlight pair; it is used with smaller specimens so is off. C is a vertical pole that holds the camera mount; the mount can be clamped anywhere along it. D is the camera mount, which has a wingnut-and-spring system to move it vertically in fine increments. (Tighten that wingnut well or the springs can snap the camera up into your face!) E is the copy stand board covered with black velvet to produce the beautiful light-absorbing background. The essential scale cards are always nearby. F is a white piece of cardboard with small light to fill in deep shadows opposite the main lit parts of the specimen. Usually reflection alone is enough fill light, but sometimes I need an extra boost.
The fancy camera is mounted! This is our latest departmental camera, purchased just last month. It is a Nikon digital single-lens reflex (DSLR) camera, model D5600. The zoom lens attached here is 18-55 mm focal length. I also use a 40 mm lens for really close work. This camera is a dream with its tilting touch screen, superb automatic focus, and multiple shooting controls.
Typically I use the aperture-priority shooting mode, shown by the yellow arrow. This gives me control of the depth-of-field since the shutter speeds can be slow with the sturdy mount. I use “live view”, which allows me to see the composed image on the camera screen. I simply lightly touch the screen where I want the primary focus and the camera takes the picture. Amazing. Occasionally I use exposure adjustments, but most of the time the lighting is good enough as is.
Here is a closer view of the most prominent trace fossil taken with the 18-55 mm lens. By the way, I have no idea what trace fossil this is. Could it be sea anemone burrows? Snail burrows? If you recognize it, let me know!
This image shows as close as I can get with the 40 mm lens, which is closer than any of our previous cameras could do. The rock is an oolite from the same outcrop of the Carmel Formation. Note the crinoid bits scattered amongst the ooids. This is the upper end of the size range for which we do microphotography.
When I’ve finished a photography session I download the images from the memory card into my MacBook Pro computer and do the post-processing with Adobe Photoshop. Most of this work is cropping, with some exposure adjustments and occasional dodging and burning in (terms that only make sense if you remember the days of film and darkroom printing!). The last item I add is the scale bar.
All the image versions on this blog, of course, have been reduced in size for quicker loading on the web. Any images I make that could be useful to others are uploaded in their original dimensions into the Wikipedia system (here is my Wikimedia index page) and designated public domain.
If you have any questions, please ask in the comments, by email or on Facebook! Later I’ll have a similar post on our microphotography systems.
These three entries on our laboratory photography systems (macrophotography, microphotography part 1, microphotography part 2) are designed to show our current and future students what we can do in our department.