A couple of weeks ago I asked what would be the best format to choose when 35mm film slides are converted to disk and consensus was that TIFF with LZW would do fine (if I remember rightly)
I sent 100 slides to karmaan who advertises on ebay. He communicated well and although his default is .JPG files he agreed to convert them to my chosen format instead. They have just arrived on disk and each file is 30-50MB !!! so no problems with the resolution either
All that for £18. Recommended
Anna