Accidental anaglyphs

October 16, 2020

Everyone knows that the very first thing you should do to improve your specimen photography is to use a tripod: it eliminates hand-shake and gives you much crisper photos. In most respects, my photographs have got much, much better since I’ve been habitually using a tripod.

But it has meant I’ve not been able to benefit from happy accidents like the one that gave me this 3D anaglyph of the Archbishop‘s Cervical S in dorsal view:

(Do you have red-cyan glasses? Yes? Good! You will be able to appreciate all the delicious morphological information in this photo. No? Go and order some right now — they cost literally a dollar.)

The reason I was able to make this very useful image is because back in the old pre-tripod days I would sometimes accidentally move a little bit between taking two more-or-less identical photographs. Here are the two images that I was able to composite into the anaglyph above:

Each of them is pretty uninformative alone: who can tell one nondescript area of brown bone from another? But when combined, they are extraordinarily more informative. If you don’t have 3D glasses then (A) get some! and (B) you can get some idea of how helpful the 3D information is from the crude wigglegram below, which simply switches back and forth between the two images.

And I can’t overstate how enormously helpful I have found these accidentally sourced anaglyphs as I write the descriptive part of the Archbishop manuscript. Even at this level of crudity, they have shown me several important points of morphology that I would certainly have missed if I’d been working only from my orthogonal-view photos, and saved me from more than one misinterpretation.

The moral is twofold:

  1. When taking specimen photographs, use a tripod — but deliberately get some pairs of shots where the camera is moved to the side by about 7 cm (the distance between the pupils in an average human).
  2. If you don’t have any red-cyan glasses, get some!

3 Responses to “Accidental anaglyphs”

  1. Sean JS Chen Says:

    You may be interested in trying out some photogrammetry software like MeshRoom so you can reconstruct 3D models of your specimens from photos you have taken.

  2. Mike Taylor Says:

    Thanks, Sean. I would love to be able to make my own 3D models instead of constantly spamming Heinrich with requests to help me out, but my experiments with Agisoft PhotoScan have never once yielded an adequate model. The least inadequate models I’ve been able to make are shown in two short videos:
    * https://www.youtube.com/watch?v=nIuJj9QJiMM
    * https://www.youtube.com/watch?v=c567EuIjnow

    I love the idea that MeshRoom might work better for me — and that this one is open source really helps. I’ll check it out when I have a chance.

  3. Mike Taylor Says:

    Rats — MeshRoom is a non-starter for me, as I have a MacBook and it only builds for Windows and Linux. Any other suggestions?


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: