studio lighting for a cruisebook photo's

My ship and I are deploying on monday for 6 mo deployment and they decided at the last minute to do a cruise book. This is similar to a yearbook of sorts. Anyways I need to shoot the portraits of about 280 sailors for a 4" x 4" picture for the book. I have a 40d with a nifty 50 and the 480 ex flash. They want a sky blue or sky background. What should I do for lighting. The studio will be a small room with haze grey or light green walls. Iam trying to go cheap as possible since this is out my pocket. I see tons of lighting setups on ebay for 75 bucks are they crap? oh they will be wearing us navy dress blue or white uniforms so color variance in clothing is not an issue.

If they want a sky blue background, could you not just do the photos on deck?

I guess im being anal but the problem then would be variance in sky color and it would be impossible to do the shoot in 1 day. Plus new crew member come on board during various point of the 6 mo time span.

OK, didn't think of that, sorry.

You may want to try just using some regular halogen bulbs, make a diffuser to throw over them, and manually set the white balance. Probably the cheapest way of doing it, and all the supplies could be gathered in one run to Home Depot.

Can you get a piece of sky blue BG paper and bring it with you? Probably space will be a problem with this I would think.

Can you get permission to repaint one wall of this temporary "studio" sky blue and then repaint when done? Easy setup, no storage, and less work for each shooting session, plus consistent BG color which would work with dress whites or blues.