Originally Posted by Super Eye
By the way if you go the digital-to-digital firewire route, it won’t be lossless. Digital-8 uses DV compression while DVD uses MPEG-2 so you’re going from one compressed format to another. It may be better than going from the analog S-Video or it may not. But it won’t be lossless.
This is indeed something to factor into your workflow choice, airspeed: I touched on it but didn't clarify as well as Super Eye just did. The compression or "loss" interactions will vary depending how you hook things up and what you use as the final files.
Going from Digital-8 firewire to Mac firewire, there should be little to no loss because its a digital>digital copy. Depending on the capture software you use, this original version will be lossless or have whatever compression that software applies. Its been years since I used iMovie, so I can't remember how it handles DV capture, but I'm pretty sure it does let you capture the unaltered Digital-8 output and save it as a backup (while compression might later be applied to any edited or retouched version). I also don't remember if iMovie wraps the original camcorder capture in a Mac-specific file container, or a more compatible format like AVI.
One way or the other, the original Mac capture can be converted to something cross-compatible like AVI, MP4 or MKV without much difficulty or quality loss. From this you can make smaller-size compressed files for tablet or phone use, and/or DVDs compatible with dvd players. (As Super Eye said, converting to dvd player format from camcorder DV will incur some additional MPEG2 loss.) The original capture files might be playable in a BluRay player if burned as a plain backup data dvd.
Going from camcorder firewire to dvd recorder firewire will involve automatic conversion/compression from original camcorder DV to dvd-compatible MPEG2. This is the big reason some people prefer to start with a Mac/PC capture instead: with the computer, you always have the original digital-8 quality archived, but with the recorder, you suffer an immediate conversion loss (that will become worse if you decide you want "tablet" or other files later). This is a subjective decision, of course: the ease of use of the recorder may be more important to you than the potentially slight loss of quality going from camcorder to dvd to tablet file (doubled conversion).
A tablet or phone screen isn't big enough to make double conversion loss really glaring, so it may not be a problem. Double conversion is a bigger issue if everyone involved eventually abandons dvd players, and instead starts viewing the smaller files derived from the dvds on a huge television. In that scenario, you may wish you had captured the original camcorder quality with a computer instead.
One clever compromise trick that works for some people is to rip the dvd thru a utility like MakeMKV, which will wrap the dvd MPEG2 video into a more-compatible MKV file (with no compression or loss of the dvd quality). MKVs will play in almost any media device, with no need for a disc player. The drawback is the resulting MKV file will be huge, the same 4.3 GB size as the source dvd. This may be impractical to play on some devices, also you lose the menu from the dvd (the copy just plays as one continuous movie file).
The above applies to your Digital-8 tapes: analog-8, VHS and VHS-C are a different sort of compromise. These will be messed with by conversion to digital regardless, and in many cases a DVD/HDD recorder will make easier/less troublesome analog captures than any computer setup. You will still face the double conversion loss if you convert the dvds to tablet-type files, OTOH you might encounter issues with analog> computer capture that negate any advantages of starting with a computer file instead.
Capturing analog video to a MacBook is a bit more difficult than with a Windows PC, mainly because the most-discussed software is Windows-only, and the dozens of Chinese analog>usb video devices tend to come with only Windows drivers. There are a few Mac-centric USB capture dongles like the original, genuine EZcap and Elgato. But they might not be necessary: you might be able to use your Digital-8 camcorder as a makeshift firewire "capture card" instead.
If your camcorder has an analog A/V input port, you should be able to patch your VHS vcr thru it. The camcorder would then convert the analog VHS signal to digital DV and pass it via firewire to your Mac (capturing with iMovie or whatever). The camcorder does the same thing if you load it with an analog-8 tape: converts the signal to digital, and sends it out the firewire port. You'd just need the correct firewire cable, and a Thunderbolt>Firewire adapter if your MacBook only has Thunderbolt and USB. If you lost it, you might also need to replace the special cable that came with your camcorder (red-white-yellow VCR A/V connections on one end, and usually a mini-headphone-type plug on the other).