Matte Fringing

[JMitchell]

I'm curious if anyone has any methods to get rid of the matte fringing caused when trying to composite two renders together. I know how to do it in Photoshop (layer > matting > remove black or white matte).

 

The thing is, that seems like such a superfluous step, especially when working with hundreds of frames of an animation. I assume there is a way to either have that done straight out of Max, OR to do it to an actual video file in a video compositing software (preferable Final Cut Pro or Shake because that's what I use primarily). I just don't know of any way to do it.

 

After Googling for a bit, the closest thing I could find was this:

http://discussion.autodesk.com/thread.jspa?threadID=548701

 

If I understand it correctly, they are simply suggesting un-checking "pre-multiplied alpha" when saving the Targa. Maybe I'm missing something but when I tried this it came out exactly the same. The only difference is that when I tried removing the black matte in Photoshop, that didn't even work so I was even worse off than the old method.

 

Any suggestions or links would be appreciated. Thanks.

[kippu]

as far as i know that matting comes only in photoshop and not in the other compositing packages

[JMitchell]

No, it most definitely shows up in Final Cut Pro.

[Crazy Homeless Guy]

i did a quick test in aftereffects. i am not sure if works the same as it does in photoshop, but try....

 

effects | channel | ...and the either 'remove color matting' or ' set matte'

 

i didn't play around with it enough to see if it is usable for an actual project.

[kippu]

it used to show up in my photoshop also but when i added them in sony vegas ...it went away

[Stephen Thomas]

In my opinion it could be an antialiasing issue. I have had this problem before when doing photomontage, if I render against a black background the rendered image takes on a little of the black around the edges. When I then paste this as a layer with alpha mask in PS over the background image, the black edge remains.

 

However, if I use the background image as a viewport background in max and render the same image with alpha, this time when I paste into PS the antialiased edge is a perfect match for the backgorund image and seems to 'disappear'.

 

Not sure if this helps, but could be the same problem you are experiencing.

[Stephen Thomas]

Sorry, just re-read the original thread, it's not the removal your having a problem with is it, more how to deal with this for a large number of frames?

 

Doesn't Photoshop alow you to set up a type of batch process to apply the same set of commands to a number of files automatically?

[anthony cortez]

For my last project, I used Combustion's Matte Controls operator > Shrink or Erode to get rid of the fringing on a sequence of rendered frames.

 

Here's a link for some more info about un-premultipling images...

 

http://www.digitalartform.com/alphaChannel.htm

 

good luck!

[Tommy L]

Either do a batch command in PS or Use AE with the import options set to premultiplied-matted with colour. You may have to adjust the colour swatch accordingly, depending on your fringe/background colour.

[erickdt]

I would suggest doing a batch command as well. Go to the actions pallete in photoshop. Create a new action. Do whatever steps you need to do (be careful as it will record literally everything you do). After you're done hit the "stop" button and you have your action. Then simply go to file-automate-batch and follow the steps in the dialogue. Hope that helps!