Taking good sequential stereo views (where you take the view for one eye and then move and take the second view) is difficult enough but combining them correctly to produce a good stereocard is as difficult, if not more so. You have to align the images both vertically and horizontally, and crop out sections that don't appear in both views. When you have two aligned views you still need to decided on which 3D format you want to display the images; parallel, cross-eyed, red-cyan, amber-blue ...
Of course, as with previous problems, the answer, as far as I'm concerned, is to write a piece of software to either 1) do the work for me or 2) make life as easy as possible. So without further ado let me show a screenshot of 3DAssembler.
This shows the side-by-side editing mode. There is also an overlayed editing mode as well as a preview mode to see the final 3D result. 3DAssembler currently supports four 3D formats; parallel and cross-eyed for freeviewing (i.e. without any special glasses) and two anaglyph formats, red-cyan and amber-blue. Lots of people have red-cyan glasses kicking around (I have four pairs from the Shrek +3D DVD, as well as a pair that came with the programme for The War of the Worlds live show) that you can use with 3DAssembler. The amber-blue anaglyphs can be viewed using ColorCode 3D glasses, which are becoming a popular way of presenting 3D content as they give better colour re-production than red-cyan (I have a pair of ColorCode 3D glasses I got free with a TV guide so I could watch a 3D episode of Chuck). Given that pictures are often easier to understand than words (certainly my words) here are examples of the four output formats for you to try viewing; parallel, cross-eyed, red-cyan and amber-blue respectively.
So if that has whetted your appetite for 3D photography you can download 3DAssembler and have a play around. If you haven't any photos to try it with then there are some example photos included in the download.
If you have any comments/suggestions about 3DAssembler or ideas for future versions then please leave a comment and I'll see what I can do.
v2.2.1 - 09/12/2014: Re-packaged so that there is an easy download available given that it is almost impossible to launch a Java programme from within a modern web browser.
v2.1.0 - 04/12/2010: You can now create portrait 3D views without having to use an external program to rotate the images. This release also includes a fix for a memory leak which should make the application more responsive.
v2.0.0 - 11/09/2010: You can now use zooming to help align the images properly, you can also now specify the exact values for the three alignment options using the advanced ribbon. The final image can also be cropped which helps to remove items that only appear in one view. There is also a custom anaglyph option where you can specify how the RGB channels should be produced. Added support for importing and exporting stereo versions of JPEG (*.jps) and PNG files (*.pns). There are also lots of performance enhancements and bug fixes.
v1.4.0 - 20/08/2010: Mostly bug fixes and a few bits of updated artwork. Also you should now find that 3da files are linked to the application so you can open a saved project easily.
v1.3.0 - 07/08/2010:You can now configure the auto layout feature based on the scene type and restrict the directions in which the images are aligned. There are also quite a few performance enhancements which should make the application work a lot faster. I've also opened up the source code -- you can get all the details from the Hudson project.
v1.2.0 - 22/07/2010: Quite a few bug fixes and error handling but the main improvement is that it is much easier to now move the images around using sliders instead of buttons.
v1.1.0 - 18/07/2010: A few bug fixes, but I've also added a green-magenta anaglyph format which should work with TrioScopics3D glasses (I've got four pairs that came with the Coraline DVD). I don't think this format is as good as either red-cyan or amber-blue but I've added it for completeness. Here is the same example as before in this new format:
v1.0.0 - 16/07/2010: First public release