I didn't know whether to post this in FPV or Aerial Photography or even Autonomous Flight.
A month or so ago, I answered a question about sending video over OpLink with basically a simple no, but I have been thinking about it. Whatever reason you have an OpLink link going, it would be very interesting to capture a picture and send it back to the ground.
Some quick calculations say that setting the OpLink data rate at 256kbps and getting less than half of that, say 100kbps would send an uncompressed image of say
64x64 16 color grayscale (2k bytes, 16k bits) in 1/6th second (plus some processing overhead for actual capture and display) which is functional for careful smooth FPV and would be interesting for watching an Autonomous Flight.
A little more head scratching and you realize that you probably don't want the Revo or OpLink to connect directly to a normal camera. Once you add an on-board processor to capture images or a smarter camera, you can reasonably get color and compression and it becomes a lot more functional. A really quick test with imagemagick gave a useful image of 106x58 16 colors in just 2.3k bytes which would transfer in 1/5th of a second but it takes a fast CPU or significant time (2 seconds on my desktop PC) to compress this high res picture. Compression is much faster for lower resolution source pictures. Find a good compromise among image resolution, image size in bytes, and compression time, and this could be useful for sedate autonomous FPV with an option to send a higher resolution image if the plane was flying autonomously and you saw an interesting "live" image.