Biggest Newbie - Yet need some seriously advanced advice. Sending data packets!

Im currently heading a team of engineers working on a high altitute balloon project. We just lost 2 genius COSC majors and now have our head between our legs on alot of the radio part:

Imagine i can read and program in C,C#,C++,Java and Basic

Some advice on best way sending binary data packets over ham radio (less hardware, most compressed)

Launching a glider of a high altitude balloon, as it glides away it is going to take pictures convert them to binary (On board) then transmit them back to a floating mothership & ground location. All while keeping a heading to a GPS location (Thats a different concern)

Any advice on how to convert pictures into a easily sendable and and decodeable binary packet would be greatly appreciated (Just a algorthim would help a bunch) i have been told to use an arduino to convert pictures into a packets

And then what frequencies and protocols are necessary to send such a packet 2-50+ miles, We have a 75 watt transceiver the we have used to send tiny track gps packets through a j pole extreme distances.

As of this second im pretty clueless, but in coming 2 months this is a major goal and will but in the time and reading required to get it done.

Any advice (Besides "Shoot yourself your screwed") would be of great help

Do you have any English majors on the team?
You haven't told us anything about the processing hardware available, or the image capture hardware..

You may want to visit the diy drone sites and forums, as many of your requirements will be similar.