Transparency issues!

 I spent quite a few (close to 20+) hours  rotoscoping  with  Mocha.

I didn't think that the original video track which was 400x300 pixels would be any problem having been embedded  into  a 1920 x 1080 composite shot.

However this caused  it to have black borders which occluded the background footage!

But I thought "Hey, I'll just Demult it; no prob!" but that turned my "good" footage semi-transparent. I tried duplicating it a couple of times and used various blending modes with not much success. Several other ideas I came up with wielded pretty much the same results.

So I resorted to positioning black planes behind my foreground which fortified the opaqueness but it just is  not going to work through the whole shot. 

And to make a long story longer: I suddenly realized that I probably could have used the shape data I had already masked to create a black solid to shadow the image (can't believe this didn't come to me sooner!)

However, success still eludes me and since I was interrupted n the middle of my attempts, I don't know yet if it will work.

No doubt there is  a super simple way I should have dealt with the whole project (beyond working with the correct resolution to begin with).

Any  suggestions or thoughts would be greatly appreciated.

Also I have several projects nearing completion and plan to start posting them soon (I hope).

Thank you in advance!

Comments

  • Triem23Triem23 Moderator

    How about luminance keying? Similar to Demult but with more control. If you don't have pure black in what you want to keep, that might do it.

    Or, can you garbage matte? You should be able to use Hitfilm's masking tool to prettt quickly set up masks to remove the borders... Yes, that's more roto. 

  • Hue and RGB key, set to RGB, will exclude only the specific colour (Black)

  • "And to make a long story longer: I suddenly realized that I probably could have used the shape data I had already masked to create a black solid to shadow the image (can't believe this didn't come to me sooner!)

    However, success still eludes me and since I was interrupted n the middle of my attempts, I don't know yet if it will work."

    It should work just fine.  As you said, apply that mask to a black plane, drop that plane to the bottom of your layer stack, and turn off its visibility.  Drop a grade above that plane.  Go to your main roto'd layer and add the Set Matte effect, and use the grade as the source for the effect.  Depending on how the roto got applied to the plane, you may have to click the "Invert" checkbox on the Set Matte effect, but it should work.

  • @jsbarrett Wow!...I just now finally saw your comment!

    I'll have to try that on something.

    Since I last posted in this thread I have restarted the project over a couple more times [but only redid the RotoWork once...well the main RotoWork, anyway!]

    I realized that I shouldn't have to fix as much as I was and that was due to terrible tracking issues [the footage I'm working with was a screen capture so the resolution is pretty crappy] 

    It's been  a huge learning experience all around.

    I'll give the details when I finally post the video in the next few days.

    I'm still a  newbie but have learned loads about how 2d and 3d work together!

    Another perfect example of how I bite off more than my, then current, masticating capacity can handle!

    Thanks again for the suggestion; it sounds like it will come in very handy!

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