How to process parallel images using a MAC. Photoshop is available. No Windows options pls, thanks.

There are no easy solutions on the Mac like Stereo Photo Maker, but I have been aligning my stereo pairs (often shot w/o slide bar) since Photoshop 3.0 first added layers. I had previous experience mounting Realist and 2x2 slides for 10 years before that so Photoshop still seems like a breeze to me.

In Photoshop, I copy the right image on top of the left, reduce transparency to 50% then look for the foreground object that I want to be at the stereo window, I drag the image to roughly the right spot then using the arrows keys I nudge the image until it is lined up. Then I go into transform mode, drag the center point to the area that I just lined up (usually bottom left or right) then rotate the image until there are no rotation errors. Next I crop the image to get rid of what is not in both images (this is a good time to check the amount of your parallax to see if it will work for your intended output..I will zoom into an area that has the most parallax and use guides to measure the total pixel displacement). Then I bring transparency on right image back to 100% and turn the layer on and off rapidly to see how it looks. Often I will have to do a very minor levels adjustment as the exposures may be ever so slightly off. Then I duplicate the image, delete the right image layer on one and the left on the other and save them as L & R....

When I shot w/o a slide bar I often have to use transform>distort on one of the images to get it to match by looking for straight lines that I can use as cues. There is a lot of intuitive guesswork in using the distortion properly.

Sooner of later I will probably install Windows 7 on my Mac and begin using SPM just to save time. I hope this helps you get started. I am sure others may have worked out a different methodologies in Photoshop but this works well for me. Good luck.