I haven't kept up with all of the responses, so I'm not sure what kind of camera Maggie is using, but my D70 automatically shoots compressed raw images. So, even though your cf card indicates you have around 90 exposures, you actually have double that. This may or may not be what Emily was referring to.
Leslie
Emily,
I have never seen an option of compressing a raw image in my canon 10D, thus can not understand what you mean by "raw is a compression too". Is it a "jpeg-like" downsampling of the original data or just a bit depth differences of say 16 bit image vesus 8 bit?
will try to google but it will be helpful to know the technical details of what it means and what are the logics applied in compression of raw files.
thanks,
achal
