Video Clip at 0% opacity still "flashes" visible

[kevina41766135]

I have a video clip that says it's at 0% opacity, but when the playhead hits the first frame of the clip, there is a visible jump or flash as the image clicks on. What might be causing this?

I'm working on a montage sequence that involves multiple layers of video clips dissolving into each other at various rates. Each clip starts at 0% opacity and is keyframed to rise to, say, 50% opacity and then drop back to 0%. At some points, there are four or five clips stacked on top of each other, all at different opacities. Some of these clips work exactly as intended, smoothly fading into and out of the image. But a handful of them have this "flashing" issue, where the start of the clip adds a sharp change to the image, even though the layer says it's at 0% opacity at that frame.

I'll admit I do not yet fully understand the different opacity blending modes (I promise to study up soon,) but changing between a variety of blend modes did not solve the problem.

At one point while trying to diagnose the problem, I was able to narrow it down to a speed effect as the cause. By nesting the clip, moving the speed effect inside the nest, and then applying the opacity keyframes to the Nested Sequence, the clip no longer "flashed" when the playhead hit the start of the clip. However, this workaround only appears to work on some of the problematic clips, while others still exhibit this problem even after nesting. That feels like a clear red flag that it's a technical bug, but the lack of similar forum posts along with my own sub-proficient understanding of opacity tells me the problem exists on my own end. Please help!

[excited_Genie16B8]

Keyframes and Speed effects don't play nice.  Try a different approach.

Set the Opacity on all clips to 50%.  Instead of keyframes, add transitions to bring them on and off.

[kevina41766135]

You're right about the keyframe/speed effect issue.

I did try using transitions instead of keyframes, and the image still pops on noticeable at the start of the clip.

I finally went the long way around and removed all of the opacity keyframes, then exported every clip individually so that the speed effects would be baked in, then recut those new files over the old ones and pasted the keyframes over. I rendered it all out and it worked! (Obviously, right?) No images flashing in at the start of a clip. Then I made one small adjustment to an opacity keyframe, and the damn problem came back! Does not make sense at all. Now I'm convinced it's a bug. I guess Premiere just has a hard time calculating too many layers of semi-transparent video all at once?

[9k305338751v8y]

Yeah, IN 2024 still having the exact same problem, I even try re-exporting, removing the keyframes, adding transitions, at this point eveyrthing but can't find a solution to this. Guess I gotta use a diffrent program for the fade in and out, or do the long way.
Still No solution for this, but thanks for addressing the problem! thought I was the only one.