Exporting alpha is RUINING my background help!
making an intro for a show, we have an animation where the background fades to black and the logo pushes in transitioning to the alpha channel, where the live broadcast will be held, every time i render it in (mac os studio) the blue background suddenly glitches to black, the alpha channel for the png logo is fine and the timeline display is perfect but every i go to render, it glitches out, i cant compound clip /render in place the transparent png and video together due to needing the png to be the alpha, what do i do? I also know that you need to render it in apple pro res 4444 and click the export alpha button, please help me. i dont want to learn adobe
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Looks like alpha channel is not interpreted correctly at some point the in the chain.
A few questions. This png, where does it come from? Who made it and how it was saved?
PNG by specifications should be with alpha channel saved as straight, but sometimes, some premultiply it. Resolve can also apply its own wrong settings, and if its double multipled at some point dark edges or jagged edges can appear, depending on how misinterpreted it is and when you are using pple pro res 4444 or some other formats that support alpha, you can additionally apply straight or premuplitpled alpha rendering.
Basically, somewhere along the line in this chain, something was either not applied correctly or was applied too many times over each other.
To troubleshoot it, you need to figure out where in your image processing chain this happens and change the settings to correct it.
Just a quick reminder, if you don't know. Straight alpha refers to RGB color channels not being multiplied with the alpha channel and premultipled alpha means RGB color channels were multipled with alpha channel.
https://preview.redd.it/euf7qt8jzdlh1.jpeg?width=672&format=pjpg&auto=webp&s=6f872b998f086eee44fc33635c3e0c8037fa7d09
First check what is the alpha of the png in the source clip attributes or by right clicking the png clip / image in the media pool and going to Change Alpha Mode....
Since its not clear how PNG was saved, by default it should be straight, but it could have been saved premultipled by someone. Eitehr way make sure that at source its all good.
You said, its good on its on in the source viewer and in timeline preview. Which leaves the export at developer page. If you are using Apple pro res 4444 there is option to "export alpha" and than "alpha mode" shows up with two options. Straight or premultipled. Try both and see if it helps. Maybe its just misinterpreted on export.
You need to export video with transparency you said? Why? Who would use it? Transparency in the video is usually intermediate stage. If you are doing all in resolve, than you probably don't need to export it.
If you are exporting it for someone else, depending on what program they use and how they work, exr format as image sequance can be smaller than apple pro res and supports all the transparency and bit depth you need.
If you are using Apple pro res 4444, do what I mentioned and see if that helps.