New to Imerge Chroma Key

MKT
MKT Posts: 2 Just Starting Out

When I import a green screen photo in using chroma key in shows my main subject in black instead of keyed out. It looks like it is reversing the chroma key maybe? How do I fix this?



Comments

  • NormanPCN
    NormanPCN Posts: 4,377 Expert
    edited November 19

    Only guessing since I don't know what you did but it looks like you used one of the auto methods (low/mid/high) for the chroma key method. The auto chose to key the red color, which is in the santa suit. Choose manual mode and then with the eye dropper, like 5x5, a select a mid point tone of the green. Then you can refine the key from there.

  • MKT
    MKT Posts: 2 Just Starting Out
    Thank you I will try.
  • Andy001z
    Andy001z Lord EarthPosts: 3,580 Ambassador

    Hi, is the photo a test you took? i.e. your green screen santa? If so it might be worth downloading a greenscreen example that is professionally done, this way you can test the effect to get it working then try and adapt it to yours. The image looks not very sharp, that might give you issues, also the folds in the background will give you shades of green that might through the key.

    I ran a test on the following image in Hitfilm FREE using the 2d greenscreen effect. No changes to setting and BOOM done.

    There is the image for you to test.

  • Andy001z
    Andy001z Lord EarthPosts: 3,580 Ambassador
    edited November 20

    I tried it Imerge 2022.2 (my first attempt at Imerge keying). It seems to have a slight spill that I am having trouble getting rid off, but its not bad.

    actually put a solid layer behind it and its not bad at all.


  • Andy001z
    Andy001z Lord EarthPosts: 3,580 Ambassador

    Here best I can do, having issues keying out the green edge, most likely because Santa isn't back lit enough.


  • Triem23
    Triem23 Posts: 20,299 Power User

    Power Tip for Chromakey in any software:

    Remember you can stack multiple instances of the key. If you have a poorly lit and/or wrinkled key you don't have to try and get every area in the same key - that's hard! Key the main green and add another instance of the key for the shadowed areas. A third for Hotspots, etc...

    Now, this next tip is more useful in Hitfilm, but should be adaptable to Imerge - don't directly key the layer at all.

    In Hitfilm you'd make a Composite Shot with your media and add a color grading effect - Wheels or Hue/Saturation are good choices - and boost up the saturation of the green. Don't worry about making the rest of the image look like crap (cuz it will). You're just boosting the green for an easier key. Chroma Key this and embed that Comp where your main media is. Now you can use a "Set Matte" to pull the alpha off the boosted-green key and apply that to the media layer.