AE equivalent to PS Luminance mask.

[Mike Fizer]

I'm a newcomer to this site and video in general. I've come from stills and have limited experience with AE. One of my most used techniques in Photoshop was to use luminance masks created from one or all of the RGB channels, combined with blending layers. (Primarily Multiply and Screen)

I've finally found a similar working solution for video by triplicating the original footage in the comp and using the Colorama>OutputCycle>GreyRamp on the top layer, then using a Luma Track Matte on the middle layer with it's blending mode set to multiply.

As amended from this tutorial: http://www.videocopilot.net/tutorials/advanced_sky_replacement/

It seems a rather clunky way of working, is there a different solution that might only require one added layer rather than two?

Many thanks,

Mike

 

[arco1]

Mike,
For one of my most powerful Photoshop techniques, I use "apply image" to create a luma mask from one (or more) of the RGB channels. I've had excellent results using a similar technique in AE for some time now, but I haven't come up with any method less clunky than yours. The simplest I can do requires three layers and often more.

Seems like there needs to be an "apply image" command in After Effects, but I doubt that we'll see that anytime soon. Let me know if you stumble upon anything. In the meantime, I've started to see if I can develop a script or macro for AE that would accomplish the same thing. I'll post back here if I have any successes.


Jim
Colorburst Video