Simple question about transition styles

Yes, I've tried to look it up in the manual, and I've googled it, but so far I'm out of luck - so:

What is the difference in how "video style" transition works, vs a "film style"?
I'm sure there's a principal for each there, but I couldn't find an explanation for it.

In my battle with wonky transitions, I discovered that if I change one that's acting glitchy from "video" to "film" (or vice versa, sometimes) the problem I have goes away. Now my transitions become smooth again.

What is the main principal on how each one works?




BTW, I never had problems with transitions not being smooth before the 18.1 update. I could select all my clips and add a single transition to them all, and it would work. Now I can do the same, but then I have to go back and check EACH transition and start changing its attributes until it's smooth again. Then if I change a transition, chances are it messes up the next one that was previously fine.

Something changed with the update, I don't know what it is, but it's creating a lot more extra work for me. Could be something I don't know / understand on how it handles a transition for a group of clips.

So I finally found this when I started reading through the manual (and yes I searched before, I just didn't get any hits for "transition style")

— Style: The different Dissolve transitions (Cross Dissolve, Additive Dissolve, and so on) expose this drop-down that lets you choose different ways for the outgoing clip to blend into the incoming
clip during the dissolve. There are six different options to choose from:
— Video: A simple linear dissolve; the outgoing clip fades out as the incoming clip fades in.
— Film: A logarithmic dissolve, simulating film dissolves as created by an optical printer.

The simple linear dissolve is what I usually need, but it comes out glitchy more often than not, and swapping it to "film" usually fixes it. I still don't know why that happens, but at least I have tools to try and fix it for each clip. Sometimes after render I may still get glitchy ones, or even spots where the transition is smooth, but a second or two later I get a glitched out / blacked out spot where there is NO transition, just plain clip.