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ljb2of3
05-11-2007, 11:25 PM
Hello all, I'm new to catalyst, and am wondering how to achieve transparency on a layer, to show the layer behind.

For example, one of my cues calls for a city scape image with clouds rolling behind it. I'm putting my clouds movie on layer one, and my city scape on layer two. At the moment, I have a black background everywhere I want to have clouds show through. Unfortunately, there are a lot of dark spots in the city image, so I end up seeing clouds all over the place when I use transparent black. White has the same issue.

Is is possible to use some other color, such as bright pink, and key it out? Or, to use the transparency (alpha) of an image to cut out parts of the image? We are using photoshop to create our images, so I can save in just about any format.

Thanks!

-Landy

tharding
05-11-2007, 11:40 PM
For Still images save in PNG.

Cheers

Toby

ljb2of3
06-11-2007, 01:30 AM
Ok, I'll give the PNG a shot tomorrow, just for reference, is this also possible with movies?

Thanks,
Landy

tharding
06-11-2007, 05:00 AM
You can use the Animation Codec set at Million+ colours. This allows an alpha channel. However it is very processor intensive and can restrict what you can play back smoothly.

There is now a basic Chroma Key style colour effect built into the software. Colour effect 6 - Transparent Colour. Works best if there is a hard edge between the image and the colour background.

Cheers

Toby

SourceChild
06-11-2007, 06:34 PM
Hello all, I'm new to catalyst, and am wondering how to achieve transparency on a layer, to show the layer behind.


Hey Landy,

Color Effect 3 is Transparent Black.
Color Effect 4 is Transparent White.

If you make your movies and you are smart to eliminate much of the gray scale from the actual graphic, you can have light images on trans black or dark images on trans white and when you use these two color features it will show the image with the white or black invisible.

Other than that, you should use the PNG feature on stills.

This is the most processing friendly way to do this.

Mr_P
07-11-2007, 01:47 AM
Tiff images with transparent backgrounds also work as well as pngs

FinnRoss
09-11-2007, 05:09 PM
Tiff images with transparent backgrounds also work as well as pngs
Tiff, when used with JPEG compression, also far less processor intensive than PNG, about 1/5 less work for computer usually.

PSD also works but puts more of a drain on the system, but still less than PNG.

SourceChild
09-11-2007, 07:12 PM
Tiff, when used with JPEG compression, also far less processor intensive than PNG

Very good point, I didn't realize this.

Mauricio Caicedo
14-11-2007, 04:11 PM
You can also use color fx 6 (transparent color) Adjust hue and saturation to match the color you want to key out.

SourceChild
16-11-2007, 11:12 AM
You can also use color fx 6 (transparent color) Adjust hue and saturation to match the color you want to key out.


Yes, however, like Toby mentioned, this is very processor intensive