1. What format is ideal for imaging PC floppy disks? From the list of options I am really not sure what to choose. I also am not sure how to process the data after imaging either. Do I need to write the data back to a floppy or is there some way to extract the useable content for access with a VM or other typical disk tools (i.e. an .IMG file)? I was especially interested in a KryoFlux unit to help me recover what I can from disks that have some possible bad spots but I am at a loss as to what to do with the data I get.
2. I have some old 5.25" floppies my dad used with a Commodore PET and Commodore CBM. They were written by an 8280 unit (I believe). What format should I use to capture those floppies? I played with those Commodores as a kid but I really have no idea what disk format they used. I have a similar question there too as to how I can read the data with something like an emulator.
2. The 8280 was an 8" drive! If your floppies are 5.25" I would try with the general CBM DOS sector image first. Vice does emulate the PET models and gives you tools to get access to the files https://en.wikipedia.org/wiki/VICE .
The 2040 is 48 tpi and should be readable with a 96 tpi drive in doublestep mode. But they had a different sector layout to the later cbm drives! Tracks 18-24 had 19 sectors instead of 18 on later drives!
I don't know if that is covered by the dtc decoder!?
Thou vice can help to get the files off such d67-images...
Oh, that's great news! So if I image them using the "preservation" mode I will get all the data?
I have a lot of these disks that I would like to try and image now and take the time to process them and go through the data later. But of course in the process I want to be sure that I capture everything on the disks before I discard them.
So is it best for me to use the preservation mode or just the -i23 argument? I assume that preservation mode will still capture the data on all the (readable) tracks?
That is a matter of opinion. Personally, I usually dump as a preservation stream and then feed the preservation stream back in to the Kryoflux software or other tools to decode it. That saves a lot of hassle and disk wear when the format is unknown or if it turns out there is copy protection. But it does mean you have to re-dump at least entire tracks if there are read errors, instead of automatically retrying. If you are absolutely 100% sure about the disk format, then you might not need a preservation stream dump.