I'm having issues capturing/solving my Nikon Z7 8256 x 5504 fits images (91 M) on the RPi. USB2 is probably one bottle-neck. In addition, when plate solving, my plate solving takes 2 minutes (when I'm able to get an image). Working with a previously saved fits file, I've just found that downsampling by 4 rather than the previous downsampling by 2 reduces the time from 126 sec to 106 sec. As shown in the attached log file.

Of interest in the log file is the message "2019-05-06T13:57:54 Index files index-4202 to index-4208 are missing. Astrometry.net would not be able to adequately solve plates until you install the missing index files. Download the index files from www.astrometry.net". It then proceeds to solve the image apparently using 4204-05.fits. Is this indicating I don't have a properly installed set of indexes?

I had to download the missing indexes 'by hand' as I couldn't see all of/use the dialog. With VNC Viewer I'm unable to see the complete astrometry index file list dialog (it doesn't fit on my VNC screen 1152 x 864) so I can't click on the relevant entry lines. The dialog doesn't appear to be scrollable for me (unlike the Mac OS version of Kstars).

Are there successful strategies out there to plate solve (large images) quickly and still be able retain the original higher res image files?

Thanks
Jerry