Interesting question, I'm not sure, to be honest.
I I dare to doubt whether real "flux" images even exist at this point.

Actually, you would have to tap into the drive's read head directly (like with an oscilloscope) and digitize the analog streams directly, using an ADC (A/D converter).

Kryoflux/Greaseweasel can't do that, of course.
On the floppy connector they attachs to, they see the same signals as the normal floppy controller would see.

These signals already have passed through several amplifier and filter stages.

So I think that the "flux" in Kryoflux is a bit of a marketing thing.

It's better than using the standard floppy controller and creating an ordinary IMA file (sector-based), but still not as accurate as it could be.

This topic will be closed soon by a mod as it related to abandonware which is forbidden on this forum (even mentioning and not linking is strictly verboten).

Mod will probably say to discuss this with the makers of this (very nice) collection.

Whew. That's a bit hard. It's like not being able to discuss current events happening in world.
On the other hand, it's their forum and their rules.. 🤷‍♂️

To me, this discussion is more about the current state of preservation, not about sharing abandonware.
If disk images are really of authentic nature (RAW).
But okay, maybe this can be discussed in a separate thread, without mentioning a specific collection.

Closed.
Ask the people that maintain the project.