HI Folks,
Does anyone have experience taking SEM images to produce stereo pairs for 3D imagery, similar to looking at topography in air photos?  I believe that the stereo pairs can be obtained using a small tilt angle of the stage (3-5 degrees?), and then overlapping the images to be viewed through red/blue glasses. Or perhaps numerous images from different orientations might be needed to obtain computer-generated images that can be rendered into a 3D model that can be rotated on the computer screen similar to SketchFab images?  Does anyone have a protocol for how to obtain these types of 3D images?  We will be using a Zeiss Supra FESEM. And then, is there software you would recommend to render the images into the 3D configuration?  I’m thinking that the resulting images would look something like the product of AFM images where we can look at the artifact  morphology in different directions by rotating the mouse or touch pad.

Any information by way of journal articles, technical reports, or your own in-house lab guides will be appreciated.  I’ll collate any responses and post to the NAGT Teaching Mineralogy resource pages.
Thanks in advance,
Dave Mogk

Yeah, this is pretty easy to do.  I find about 5 degrees works pretty well, and you can experiment with your samples.  "Taller" samples may benefit from a slightly smaller angle.  Just acquire your image, tilt, acquire again.  Make sure your acquisition time is sufficiently short so there is no drift in the image because that will show up as a skew and damage the stereo effect.

For the data processing, there are several software packages available depending on your OS and preferences.  Search for anaglyph or stereo pair.  However, I've mostly used Fiji (imagej).  You can put them in a stack, align (usually something like stackreg works well), sometimes you need to translate one a bit, and then turn them into RGBs.  If you have a lot of skew (because you wanted a 4k stereo pair...) then you can try an affine transformation for the alignment, maybe you'll get lucky.

To be honest, the best way to view these in my opinion is to place them side by side on  your screen (maybe you have to rotate them 90 degrees so the tilt axis is vertical) and then cross your eyes.  This has the advantage that you can do it immediately on the SEM while acquiring the images so you'll know if you captured good images.

Zack

From: Mogk, David via MSA-talk msa-talk@minlists.org
Sent: Wednesday, October 16, 2024 2:16 PM
To: MSA-Talk@minlists.org msa-talk@minlists.org
Subject: [MSA-talk] Stereo-Pair Images on SEM?

HI Folks,

Does anyone have experience taking SEM images to produce stereo pairs for 3D imagery, similar to looking at topography in air photos?  I believe that the stereo pairs can be obtained using a small tilt angle of the stage (3-5 degrees?), and then overlapping the images to be viewed through red/blue glasses. Or perhaps numerous images from different orientations might be needed to obtain computer-generated images that can be rendered into a 3D model that can be rotated on the computer screen similar to SketchFab images?  Does anyone have a protocol for how to obtain these types of 3D images?  We will be using a Zeiss Supra FESEM. And then, is there software you would recommend to render the images into the 3D configuration?  I’m thinking that the resulting images would look something like the product of AFM images where we can look at the artifact  morphology in different directions by rotating the mouse or touch pad.

Any information by way of journal articles, technical reports, or your own in-house lab guides will be appreciated.  I’ll collate any responses and post to the NAGT Teaching Mineralogy resource pages.

Thanks in advance,

Dave Mogk