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View Full Version : Using keylight without a greenscreen

Indesium
05-06-2006, 10:03 PM
I was doing a lot of work with Keylight and greenscreens for awhile, and so I worked with Keylight quite often. I'm looking to take a black and white jpeg I have though and, using keylight, make the white part (the logo is black) transparent. Everytime I try this, it doesn't work.

Is it impossible to do with Keylight? Or is there a possible problem with the image I'm trying to use? (I tried using other programs such as photoshop, illustrator, and paint but they all refuse to let me fill the white area with color)

Is there another tool/effect that will make the white transparent?
Indesium
05-06-2006, 10:20 PM
I would just like to say that I figured it out. :)

What I did was I opened the image in photoshop and under modes I changed it to RGB and was able to add color. and then in turn make the white part transparent by first making it green

But a question remains: How come Keylight, if the option to select white and black colors is possible, doesn't accept them as usable? I mean, when you first open the keylight feature, black is selected as the eyedrop color.
AAAron
05-07-2006, 12:35 AM
I donīt really see the point since a black and white image also works great as an alpha, use LAYER-> TRACK MATTE-> luma or luma inverted instead. Or you can use the EFFECTS-> CHANNELS-> SET MATTE and set it to use luma. If you want to tweak the matte its easy using levels or something similar on the layer you use as matte. Hope this helps :)

Of course this goes mainly for black and white images, even if you can use a color one too the colored parts doesent have zero luma value and will be semi transparent. Though that could be tweaked with using levels or brightness contrast.

Anyways it sound as it something weird going on with your image, since you canīt fill it in photoshop.

Last of all if the logo is to remain in black and white the easiest way is to just use darken as the transfer mode on that layer.
Indesium
05-08-2006, 12:01 AM
In the long run (so far) the logo is turning out pretty cool (I added a glow, made it look flame-like, and put a wav clip behind in to add fire sound)

The problem with the image ended up being that it was saved in grayscale and it could only be edited in grayscale mode. Basically in Photoshop I just changes the mode to RGB and that was that.

I took note of your suggestion though. I rarely use luma and alpha matte stuff so it wouldn't be the first thing to pop into my head. Could be useful though.
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05-08-2006, 12:01 AM
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