Lensboards for Macro Stereo :confused::confused::confused:

[Mark Sawyer]

Let's say you want to do stereo at near-macro distances. You'd need to angle the optical axis for each lens inward a little bit so they both pointed at the main subject. Was this done historically? It seems it must have been, but I've never seen nor heard of one. Was there a stereo lensboard for any format that was adjustable in that respect, for different distances?

(Note to forum: emojis don't work in the subject heading. :) )

[pgk]

Well, I have one of a pair of stereo lenses from the mid/late 19th century which came on a 'half-board' that was clearly intended to be adjusted. I assume that it was so that the inter lens distance could be adjusted for different focus settings, but not having the camera nor other lens and board I can't check. Single lens stereo cameras for static subjects would have been highly adjustable though. Here's one that has the two lenses mounted on a split board so I assume that their separation can be altered: https://www.antiq-photo.com/en/collections/museum/cameras/stereoscopy/chambre-photographique-a-tiroir-stereoscopique-a-bascule/

[Mark Sawyer]

Thank you, pgk! From the sliding-in-the-slot mount to the camera you linked to, it appears the spacing can be altered, but not the angles. Perhaps you're right that it was done with single lenses shot separately.

[Chauncey Walden]

Mark, I'm sure you know the Macro Realist just had closer spaced lenses and the 4 lens Nimslo could be used for macro by putting a diopter on the 2 inner lenses. Otherwise I think it would just be handled with offset frames within the camera. I know it is not totally correct to do so but I tended when taking macro photos using a sliding mount to center the mount with perpendicularly mounted camera on the subject and then shift the mount an equal distance right and left from center and repoint the camera at the subject. Worked fine when doing stereo photos of insects in amber. To put it another way, a 2 lens stereo camera has offset film frames but a single lens camera must use a movement of the entire camera for the offset. Not strictly ortho but works good.

[Mark Sawyer]

Shifting the plate position instead of the lenses? Now that's a solution I hadn't thought of! Thank you, Chauncey!

[brighamr]

another way of doing macro stereo is with two cameras thru a half silvered mirror/beam splitter

very tricky to line up but with two Sinars or other technical cameras it is possible to perfectly line up the images and then off set by a mm or whatever you calculate you need
i've done this in the past to get multiple exposures at the same time with a lens on each camera into the mirror but i guess you could use just one lens on the other side of the mirror

best

robin

[Maris Rusis]

And another way of doing macro stereo still life pictures is to put the subject on a turntable and rotate slightly between exposures. The background and lighting should be uniform or alternatively rotate with the subject. Did this with 35mm way back last century. Can't find (not surprising) the technical notes.

[Mark Sawyer]

And another way of doing macro stereo still life pictures is to put the subject on a turntable and rotate slightly between exposures. The background and lighting should be uniform or alternatively rotate with the subject. Did this with 35mm way back last century. Can't find (not surprising) the technical notes.

That would, of course, require two separate exposures, hence, as you said, still life only. I'm being picky about using a conventional stereo camera, an admittedly arbitrary restriction on my part.

[Drew Bedo]

Could careful use of front movements be made to work. . . .?

[Mark Sawyer]

Could careful use of front movements be made to work. . . .?

I don't think so. The movement needed for a close-range subject would be angling each lens inward so that each points directly towards the subject.