Oh boy, archiving floppies!
Well...
*rolls up sleeves*, let me try to shed some light on what I've learned. My apologizes for the book! (There is a TL;DR below)
Introduction
I'm not an expert, but a lot of smart people have helped me over the years. Please be aware that I'm just typing this from my memory, so things may not be exact, etc. Anyone reading this, feel free to correct things. I own both a Kryoflux and an Applesauce and have some novice experience with both.
I can't speak to all forms of copy protection or situations, but generally speaking a modern disk imaging device like KryoFlux or Applesauce will give you the ability to better archive disks with some pretty neat features and recovery options. Both offer the ability to try and re-read any bad sectors you may encounter while reading disks. This is very helpful, as on a real Mac either DiskCopy (or whatever app) usually won't re-try and will simply fail with a generic error that the file or disk couldn't be copied. Also, usually to archive 400K disks, they won't be read on Mac OS 8 or higher (unless using DiskCopy 4.2). So you may prefer System 7.
For years this is what I battled with, and when a file or disk refused to read, I just set it aside and hoped that sometime in the future this would be resolved. Thankfully the Applesauce and Kryoflux do help you to a degree. They won't fix all damaged disks, but I‘be been amazed by what some alcohol and re-trying could do.
The Kyroflux:
It uses a standard PC 3.5" floppy drive, apparently I just happened to have one of the Sony model drive that play nice with Apple 800k/1.4 MB disks. I got mine in the summer of 2021 and used it a number of times. Their software is straightforward although you sometimes need to manually select the format, or guess from the drop-down menu. From what I recall "MFM" disk is the format for Macintosh disks (1.4MB) and the "Apple DOS 400/800K" option is reserved for earlier Mac / Apple II disks. I had to hunt around for some details about archiving Mac disks, as most people don't buy it to do that. Also, don't think the secondary port on the Kyroflux is for a Mac floppy drive, although it looks like one may fit!
I've had pretty good luck imaging disks, but have found that some disks confuse the software so they don't know what type of disk it is. It may let you archive it anyway, but it won't identify the disk type/structure. Sometimes these problematic disks would actually read in my vintage Mac just fine. It could be an error of me using the software (very likely) or maybe the disk was kinda messed up (also very likely).
The Kyroflux saves images in .img format, but you have the option to do "preservation" reads of a disk. But I haven't looked into that (although I've used it out of curiosity a few times). These .IMG files will work in a Mac emulator or can be mounted on a vintage Mac (assuming you fix any resource fork issues or file type associations with ResEdit). Overall, the Kyroflux is a neat piece of kit, and if you want to archive Mac or PC disks (and have the right disk drives) it's a good option.
The Applesauce:
As the name hints, is specifically tailored to Apple systems. Most people probably know it for archiving Apple II disks, but it works beautifully with Macintosh disks too. You just need to supply your own external 19-pin 3.5" 800K or later floppy drive. I've been using one that came with a second hand Mac Plus. Of course you'll need to change out the eject gear, lube up the gears/rails and clean away the decades of dried up crud. But once you've done that, it works beautifully. You can also use a 1.4MB "SuperDrive", but the instructions I found said it must be installed using the adapter board inside Apple external 3.5" 800K drives. Thankfully I had one with a bad drive, so I installed my SuperDrive and it worked well. Giving me the ability to archive 400K, 800K, and 1.4MB disks. I've archived probably 100 disks so far, and the software makes it a breeze.
There isn't much guess work as it's designed for Apple and Macintosh disk drives. You can optionally add sensors and such for your disk drives, but I've found it's not needed for the 3.5" disks. There are two main imaging modes, Flux, and Fast imaging.
Flux mode produces a deeper level scan which is best for awesome people to better remove copy protection and analyze the structure of the disks. Their website does a better job of explaining this, so I won't pretend to understand all the benefits. My general rule of thumb is to do a fast image first, then (if it’s a commercial disk) do a flux image, as it takes more time. Most generic disks (unless it contains something interesting), I’ll just use the fast imager process.
Fast imaging is, well, faster! It usually takes under 30 seconds for a 400K disk, about 1 minute for a 800K disk, and a bit longer for a 1.4 MB, assuming you don't need to re-try for errors. The best part is that it gives you the option to retry bad sectors as many times as you want. This gives me the chance to eject the disk, open the shutter, and wipe away grime or put a dab of 91% or 99% isopropyl alcohol to try and eradicate read errors (which surprisingly works every well!). Or clean the heads of the floppy dirve, which you'll want to do very often. Sadly, the Flux option doesn't let you re-try bad sectors. However, wizards on the Applesauce discord were able to combine info from a Flux dump and Fast image dump of my Excel version 1.00 to get it working. So... its magic?
Fast Imaging (and Flux) also let you know if files are damaged or incomplete due to bad sectors. This is VERY handy, as you can figure out if a crummy disk with bad sectors is worth battling or not. It usually is, but it'll give you a heads up if a file is effected or not.
For Macintosh disks Fast imaging lets you save a .dc42 (DiskCopy 4.2 format, basically .img) or .Moof (a bit stream format for geekier purposes like running copy protected software). For Apple II disks you have .WOZ o. The Flux format gives you an .a2r Applesauce file. This contains a bunch of extra fancy info, but can also later be extracted to a .dc42 or .Moof file. Again, the big risk is if the disk is cranky, you can end up with bad reads on a sector (which the visuals will show) and you can't re-try just those bad spots without re-fluxing it, which takes about 2x as long as a normal "fast" image of a disk.
Using a Real Mac
Using a real Macintosh with a SuperDrive and System 7.X is another option. I'd avoid PCs and Linux options just because 800K disks aren't fun to get working on non-Apple systems. I won't argue if it can be done because I've seen some stuff... but I wouldn't rely on it to archive disks.
Using real hardware has some pros and cons however. The preferred app by many is DiskCopy 4.2, as it'll capture "tag bytes" from the disks. Apparently these are usually unused on Mac disks, but for a completionist (and maybe rare cases they are used), that is good to be aware of. Personally DiskCopy 4.2 has been cranky to me and doesn't like most emulators or some Macs. However,
apparently it should run fine on most 68K and Power Macs in Mac OS 7, 8 and 9. DiskCopy 6.3 is newer, but won't capture the "tag bytes" from the floppy disk, but it will let you mount disks on your desktop after imaging them. You can also use it to mount most DiskCopy 4.2 images, but ShrinkWrap 3.5 can help with stubborn images.
Unfortunately, when making a disk image from a floppy... 9 times out of 10 the image process fails due to an error. It's probably because a sector couldn't be read and the system doesn't give you the option to retry it. This sometimes this forces me to copy files manually off the disk (which sometimes work fine, others not). But for commercial software this isn't ideal as hidden files and other data may not copy via that method, etc. Now maybe there's a good way of sector-reading floppies on the Mac that I haven't stumbled upon (or remember) it.
I've even used an iBook with a USB floppy drive to image 1.4MB disks, but of course this won't work with older 800K or 400K disks.
What to archive and Unsealing Boxes
My suggestion? Archive EVERYTHING.
EVERYTHING!! Is there already a copy on MacintoshGarden? Archive it anyway! The disk image may be missing a file or may be a different version. Not all printed labels are accurate, or maybe your disk has a patched update or Read Me file the other doesn't. It's easier to make a huge stack of disks and just archive them all. It doesn't hurt to have a second copy, because some of these archived may not have been copied right, or may be incomplete (at no fault of the archiver).
You can usually unseal a box carefully, even prying the box flaps open with tweezers to not bend the cardboard, to get to those sweet disks inside. These disks are getting up there in age. Thankfully sealed disks have a better chance of reading fine, but nothing lasts forever. So unless it's something super rare, like Alice: Through the looking glass, you could carefully unseal it and preserve the disks.
Organization and Sorting
Make yourself a spreadsheet to keep track of the disks, it'll keep you sane (...well kinda). I'll share an example here soon. I used a #2 pencil to write on the back to keep track of disks. It'll easily wipe away if needed and won't harm it. But when you have 50 floppies on your desk, everything seems to look the same (especially if they are generic disks). I usually write something like #A22 or #B33 to keep track of batches I work on.
Once I've attempted to archive the disk I have three bins to place them in. Bin 1 is "100% Good", this means that I was able to archive the disk and even if it had bad sectors, they were eventually readable via cleaning. Bin 2 is "Mostly good" the disk may have read errors, but I've tried my best. I can return to these later if I'm feeling lucky. Bin 3 is "Dead", ether they have too many bad sectors, or they have physical damage. Bin 4 is "Unknown Format", both Kryoflux and Applesauce will shrug if it can't understand a disk, I like to sort these out in case it was user error or it turns out to be something special.
Oh, and certainly take photos or scans of the fronts (and if possible backs) of the disks! Sometimes the back of the disks have a sticker or label with a serial number, version number, or copyright date, which helps date the software.
Nursing Disks to Read
A number of times I'll get the Applesauce going and one disk will be very, very unhappy. It may read initially with 12 bad sectors, but maybe you can get that down to 3 by retrying... but then it gets stubborn. Even if you attempt to re-read a disk a dozen times (I've done it before), they may not budge. Thankfully some 91% or 99% isopropyl alcohol is your friend. Cleaning the heads of the floppy drive and the platter of the disk itself has helped me. You don't want to drench it, but a dab or a swab can be very effective. Don't give up either, sometimes I've had to re-try over a dozen times, but was eventually successful!
Conclusion (TL;DR)
Both sides will claim they are the best. It's obvious that the Applesauce creators had Apple/Mac users in mind and they have a few unique tricks just for our disks. However, due to supply issues they aren't being sold at the moment (as of January 2023). This leaves the Kryoflux, which will require a power supply, a sorta specific Sony 3.5" PC floppy drive that will mingle with Mac disks, and some bravery to ensure you are selecting the right type/format disk when archiving the disks. Using a real Mac may work well, unless you get some problematic disks with bad sectors.
In a perfect world all of these tools would be easily available to everyone and all disks would read happy. But it's super understandable to have to make a choice between what you can afford (or find) and how much time and effort you want to put into things. Archiving these disks is a great thing to do, and if it's worth doing, it's worth doing right (and spending the time do things properly of course). However, do the best you can and keep your records. That way when you come across problematic disks, or things with copy protection, you can set them aside to send / share with others to try them out. I’d be more than happy to help with my Applesauce.
Both will work well enough with *most* disks that are in good shape. Both will likely let you image a slightly cranky disk... However, I've been more impressed with the Applesauce's abilities to recover bad sectors. That being said, in full disclosure, I just got the Applesauce recently and it's been top of mind. I really should do a comparison video about these little devices. As maybe my memories about the Kryoflux are a bit hazy.
I hope this helps! I'll go back and add images and links soon.
-Steve