Delanie -- PinPoint can't use JPEG Sorry. The FITS files contain information needed by PinPoint like the exposure start time (for proper motion calculations) and the approximate RA and Dec (to avoid having to search the entire sky). By doing a Google search "convert JPG to FITS" I found many utilities and web sites. I haven't tried any of them. Use caution on web sites, some nasty sites use your search phrase to suck you into one that delivers malware. Use caution on any downloaded programs as one might be malware itself.

I would find a way to save your original images as FITS. Any non-trivial astronomy is going to need that format.