Scientific Photography

by Jackson Chu

We all have indispensible tools we use in science. A sturdy bucket for sampling intertidal critters and seaweeds. Our trusty calipers for measuring morphometrics. Our favorite R-package for numerical ecology. All these are important for doing science. My favorite tool for scientific communication and outreach are pretty photos! A good photo can captivate and create interest in your work and, more importantly, let you communicate science to a much greater audience.

3 sponge classes

Three classes of sponges. Left: a calcareous sponge (Sycon sp.). Middle: a carnivorous demosponge (Asbestopluma occidentalis). Right: a juvenile hexactinellid (glass) sponge (Aphrocallistes vastus). All scale bars  = 1 cm.  © Jackson Chu. All rights reserved.

How did I take those photos?

There are a few key ingredients: (1) a digital slr, (2) a  50mm lens or 28mm lens, (3) a reversing ring, and (4) a flash that can be used off camera. (e.g. with an off-camera sync cord)

My science photography kit.

My science photography kit.

My science photography kit.

As a graduate student living on mac and cheese, I cobbled together my used camera equipment from various online sources (e.g. eBay). The camera brand really makes no difference. I would estimate I spent ~$300 for everything:  $200 for the camera, $50 for the lens, $2 for the reversing ring, and $50 for the flash. Because I am always working with small (but not microscopic) invertebrates, one trick to close-up (macro) photography is to mount the lens backwards onto the camera using the reversing ring.  A 50mm lens mounted backwards onto a camera will give you a 1:1 magnification ratio (1 cm object will be 1 cm on the camera sensor).  A backwards mounted 28 mm lens will give you a higher magnification ratio of 3:1. There are also other alternatives that yield similar results: macro-focusing teleconverters, extension tubes, or dedicated macro lenses.  In order to get proper lighting, a flash will have to be oriented close to the object. You can do this in one of two ways. Modern day flashes can be wirelessly triggered from the camera. Otherwise, an off-camera flash cord can be used.

Most of the time I’m trying to take photos of my live study organisms.  What’s worked for me is to use a shallow, flat-bottomed glass tray filled with filtered seawater. Petri dishes work great for tiny 1-cm critters like carnivorous sponges. Glass baking dishes are great for >5 cm sized critters like nudibranchs and seapigs. I usually slip my neoprene laptop sleeve underneath the tray of seawater to create a black background in my photos.

Here are some examples!

Nudibranchs from Scott's Bay

Some nudibranchs from Scott’s Bay, Bamfield. Left to right: orange peel nudibranch (Tochuina tetraquetra), white lined dirona (Dirona albolineata), opalescent nudibranch (Hermissenda crassicornis), and clown nudibranch (Triopha catalinae). © Jackson Chu. All rights reserved.

Scotoplanes globosa

Sea piglets. Juvenile sea pigs (Scotoplanes globosa) sampled from 1500 m in the northeast Pacific Ocean. Each sea pig was ~5 cm in length. © Jackson Chu. All rights reserved.

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The Octopus of Saanich

By Jackson Chu and Danielle Ludeman

As part of the Oceans Network Canada observatory, the Victoria Experimental Network Under the Sea (VENUS) provides real-time measurements, images, and sound to researchers and observers on-shore.

Anyone, from scientists to the general public, can access the network’s data and monitor environmental changes as they happen (see here for a previous post on accessing and graphing VENUS using R). The VENUS instrumentation is found in the coastal waters of the Salish Sea and is the sister network to the offshore NEPTUNE Canada regional cabled ocean network

Video and data provided by Jackson Chu

Captured in this time-lapse video from Saanich Inlet is a juvenile, ~10 cm long, Pacific Red Octopus (Octopus rubescens), which had temporarily moved underneath the VENUS Camera Array for a month. When the oxygen levels drop to near zero, it decides to pack up and move somewhere more hospitable. You would to if you had a dozen squatters (Munida quadrispina) hanging around your neighborhood all day!
Note: You can see the white ball sponges (Suberites sp.) contracting in the video – the first time this behavior has been captured in situ on the bottom of the ocean. You can check out another time lapse of a contracting sponge done in the lab, Tethya wilhelma, and one of a freshwater sponge Ephydatia muelleri.

Metadata:
Location: Saanich Inlet, 96 m depth
Camera: Olympus C8080WZ
Exposure Settings: 7mm @ F5.6, 1/30s, ISO100, with offcamera strobe in custom housing
Time start: Sept. 14, 2012 @ 07:47:42 UTC
Time end: Oct. 09, 2012 @ 14:47:28 UTC
Total # of images: 1691 8MP still images (3264p x 2448p) taken in doublets (10 s interval) every 30 mins
Workflow:
Images were batched processed to 1440p x 1080p dimensions (Adobe Photoshop) and made into a 15 frames per second (fps) time lapse movie (Avidemux). The time lapse video was then stabilized and re-rendered (Adobe After Effects) because the images did not perfectly overlay on top of one another which resulted in shakey raw footage. Oxygen data profile for the time sequence was downloaded from the VENUS website, processed (Matlab), and plotted (Adobe Illustrator, Adobe Photoshop). The Oxygen profile was then overlaid onto the time lapse video (Adobe After Effects), and an animated time marker was added using keyframes before finalizing the video by pillarboxing into a 1080p HD-video with audio accompaniment (Adobe Premiere Pro).