If you are using a Mac you wont have those color variations between programs, unless you've whacked out your colorsync settings. I always export as a TIFF image. If memory serves me correctly Poser doesnt use the LZW compression, but if you see it as an option apply it. The compression is lossles and does save some space. With the TIFF format you can also hold layers and chanels to handle alpha maps, etc. When you export an animation you can either choose some Quicktime settings for compression at render time or render out the Movie with no compression (Compression/None). That way you can use Quicktime to later make several different versions of your movie from one clean source.