Q: What is difference between Cross-Dissolve Video and Film?

Hi,

Here is a comparison between fade made with opacity, then cross-dissolve film, then cross-dissolve video, all in one row of a video collage.

Viewer


Scope


I can see absolutely no difference between all this, but I'm surprised I don't see any between cross-dissolve film and video as they are two options of the same transition. I tried with saturated color also to see if this was a saturation related thing but no difference either.

What do I miss ?

Thanks!

Step through the transitions one frame at a time and you'll see the difference.

@Jim Simon
I still don't see any, but a technical explanation would be much appreciated.

You're looking at the footage when you step through (not the scopes)?

A video dissolve is steady and continuous, a smooth ramp from one clip to the other. The film dissolve effect attempts to replicate the effect created on an optical printer, where the progression from one clip to the other is not uniform and the light levels of each clip will determine what the frame looks like at any given moment.

You can most easily see the difference in high contrast clips. What you're testing above is not a good example. You want abrupt changes between the two clips.

@John
Thx for detailed explaination but I still don't see the difference even with 100% SMPTE bars



Can you provide a valid exemple so I can in which contetx it do has effect ?
Or maybe it doesn't do anything cause these doesn't fade from another layer ?

Use normal footage. The difference between Film and Video in Cross Dissolve is pretty obvious.

Shoot indoors with low light and outdoors in bright light. Then dissolve between the two shots. Or shoot outdoors in bright light and dissolve to black. Then step a frame at a time and observe the difference.

The difference can be subtle. Here are 4 different dissolves one after another.

Dissolve Variations.jpg (125.18 KiB) Viewed 4898 times

@Charles Bennett
Thanks for taking time to upload!
I can see difference between these, they are less subtle than film VS video option of the cross-dissolve transition (which isn't showcased in your timeline)

@John
Don't need to shoot I can just take photos online,
or go with black and white image



There is a clear difference indeed in this case, video is the one is the slower ramp (cause linear)
so maybe it is more related to what it is crossfading too, and if there no media, then film and video modes behaves the same

In real situation, I suppose this has to be tested case by case then.

Thanks for the investigation!

The Additive Dissolve is almost identical to a film dissolve.

A video dissolve is linear, and happens at a constant rate.

A film dissolve has essentially an S-curve, so it starts quickly, slows down in the middle, and speeds up at the end (or you could change this to starting slow, speeding up, and then ending slow again). Chemical film dissolves done in a laboratory have a distinctive look where things start getting crushed at the end. To tell you the truth, when I remaster film projects, I try to avoid that kind of look and I "de-crush" it when possible so it's a little less loggish and heavy... but it depends on the project and depends on the look.

Whenever I conform features -- even digital features -- I always use film-style fades and dissolves, because it just subjectively looks better to me. A linear fade or dissolve just looks like "TV" to me, kind of cheap and tacky. Modern editors don't think about it, but it was a "thing" when Avid first started in the early 1990s. It's yet another artistic choice, and it's not necessarily right or wrong... it's more a question of "what looks right to you?" Old school film editors will almost always, always use a film-style fade or dissolve.

@Marc Wielage
Thanks for the detailed explanations !

It is indeed more clear now, I guess what was mostly needed is working example, cause what my initial tests reveals is that Film and Video mode will not behaves differently if transition fade to void.
We saw later that that it worked as expected with black shot to white shot transition (ot any shot to shot transition).

So there are some edge cases, where the behavior difference doesn't show up.

The thing to look for is that the brighter areas will hold longer than the darker ones with a film dissolve, as if the highlights of the image which is fading out are "clinging" to the shot. You can also recreate various optical effects with keyframing, holding certain portions longer than others, or speeding up or slowing down the dissolve. But if there's little contrast in the shot, the difference may be hard to see.

I am one of the old school film guys, and I always use the “film” dissolve, as it looks much better to me.

I've always seen highlights opacity hold longer/come on more quickly on film dissolves vs cross dissolves.

Reminds me of adjusting opacity when using 1.0 gamma rather than 2.4 or whatever

Video dissolve is linear. Every pixel will change at the same pace. Film dissolve emulates how a film behaves. Light passes slower on thicker density portion of a film stock (aka dark). So the lighter portion of of an image changes more quickly compared to the darker portion. Remember the calculation is done through bought sources.

I am one of the old school film guys, and I always use the “film” dissolve, as it looks much better to me.

I think that's the better paradigm to hold on to. I kind of cringe when I see a big-budget show or feature that's using linear fades or transitions, because it's just a little too "electronic" to me.