Hmm, I didn't get a new-post notification for your reply despite being subscribed to this thread.
I am working under the assumption that the disk_* values under the man_Other category refer to the kind of physical drive used to image the media, possibly without prior knowledge of what's on the disk. If I'm not mistaken, I'd interpret the existing definitions as:
- disk_360 => 5.25" DD drive
- disk_12M => 5.25" HD drive
- disk_720 => 3.5" DD drive
- disk_144M => 3.5" HD drive
I believe that the common 8" disk drive distinctions (among Shugart-interfaced drives that can be connected to an SCP with an adapter) are:
- single-sided, 77 tracks
- double-sided, 77 cylinders
SS and DS 8" drives use distinctly different media, with DS drives commonly being able to detect when SS media is inserted and alert the controller with a bus signal (much like 1.44M 3.5" drives can tell DD vs. HD media apart). There was also 8" media made with index hole windows for both SS and DS drives so that either kind of drive could use it, but I don't know if such media would behave consistently when moved from one kind of drive to another. With that kind of media, you can't infer ahead of time whether the data will be SS or DS.
I'm not aware that it was common to refer to 8" media and drives by their nominal capacity like it was for 3.5" and 5.25" media/drives, so I don't know what capacities would make sense. I've generally seen 8" media referred to generically as SS or DS, or less generically by manufacturer-specific drive+format designations like RX01 or RX02 by DEC, or Type 1 or Type 2 or Type 2D by IBM. It was even common to mix FM and MFM on the same disk; I believe it was customary for track 0 side 0 to be FM with 128 byte sectors regardless of the formats on other tracks,. And then DEC used FM sector headers with MFM sector data on their RX02 drives to make things more interesting. It makes sense to me to define disk_* values for 8" SS and 8" DD drives, since those are distinct physical drive types.
In any case, I'd recommend defining a disk_other value, because I'll bet that somebody shows up with a distinctly different drive type that none of us have seen before. A distinct "none of the above" value seems like a good idea to me, since you've clearly put in a lot of thought towards making the SCP file format extensible for broad use.
As an aside, I've recently used my SuperCard Pro to image and archive some software for the TRS-80 Model II line of computers which was previously thought to be lost, after finding it in a large box of dusty old 8" diskettes that were apparently store demo copies at some long-dead Radio Shack Computer Center. It'll find its way to a public archive eventually. Three cheers for SuperCard Pro!!