Bad Keying - Photoshop files

[M***@adobeforums.com]

This is a simple way of illustrating my problem.

I've created one .PSD of solid colour (eg red R=255, G=0, B=0) and saved this as file 1. I've then created a 2D image (eg some text, a box, a squiggle - anything) in the same red over a transparent background, and saved as file 2.

When I place file 2 over file 1 in Premiere Pro it will automatically key out the shape - and theoretically I shouldn't see anything except solid colour as both files are the same - but what I am seeing is really bad edging on the key.

In Premiere 6.5 transparency settings, I often found that White Alpha Matte was better than Alpha Channel and this would cure the problem. But - in Pro I dont have the option of White Alpha Matte and I can't see how to make a really good key.

Please advise if anyone knows the answer as I'm tearing my hair out! I often have to use this effect for masks and mattes - and i'm not happy with the edging problem

Many thanks all!

Matt

[E***@adobeforums.com]

Matt, please upload the PPro project file and the two PSD files to this site <http://groups.yahoo.com/group/APProHelp/> so we can have a look.Cheers
Eddie
Forum FAQ <http://www.adobeforums.com/cgi-bin/webx?14@@.2ccd4455> PPro Wiki <http://ppro.wikicities.com/>

[Craig Howard]

Why do you need the red bg layer if the other layer is transparent and of the "same" color as the bg?

Why are you keying this at all?

Red is a very bad color to use in any key.

What are you trying to do ? I suspect there is a better way of achieving it.

[P***@adobeforums.com]

My advice: don't do chromakey work in PPro. Use AE or Combustion or Ultra or a plugin (Ultimatte/Primatte/Boris Red/...).

[M***@adobeforums.com]

I was just mearly using this as an example to make it really simple!

I'm just saying whatever I am keying on a transparent background I am getting bad egding effects which I dont want! It's not chromakeying i'm trying to do - it's just a simple overlay of a .PSD file.

I want to keep all my graphics in Premiere as it usually does it so well - or at least it did with 6.5. I'm positive there is something i'm doing wrong, but i dont know what. If only it had White Alpha Matte as that always gave a perfect key.

[E***@adobeforums.com]

Matt, without being able to see what you're talking about I'm afraid I am of no help to you.Cheers
Eddie
Forum FAQ <http://www.adobeforums.com/cgi-bin/webx?14@@.2ccd4455> PPro Wiki <http://ppro.wikicities.com/>

[D***@adobeforums.com]

How are you creating the original PhotoShop shape? Any chance that you are using a feather-edged brush?

What happens if you create a vector shape - eg circle or rectangle - with a hard edge?

[Craig Howard]

Why are you keying an object already on a transparent bg?

Assuming the object has an alpha channel there is no need to key it again in PremPro.

[M***@adobeforums.com]

Craig - that is the problem! The alpha key in PremPro had bad edging!! And - a vector shape produces similarly bad results.

My keys sometimes have soft edges - thats the effect I may need! It worked beautifully in 6.5 with soft edges - but Pro is producting bad effects.

Try it yourself - grap a still frame of any picture - and then paint some of it out in photoshop so that it is transparent so you have a mask. When you key it back over the original file in Pro the top layer is clearly keyed over the top. In theory it should be completly un-noticable as you are keying part of the same picture over itself!

You may ask me why I am trying to do this! One example is a shot where the microphone is in the top of frame. I normally simply grab a still in photoshop where the mic isn't seen and erase the rest of the frame so I have a still image where the mic is waving around. Then key this clean view back to hide the mic! I did this all the time in 6.5. I admit there maybe other ways to do this - but this is the way I would like to do it as keying a photoshop file should be so straightforward.

[D***@adobeforums.com]

I wonder if it your technique somewhere?

Starting from a still image at frame size, as you would with a frame grab, I marked out out the area of interest with a marquee which I then feathered from the Select menu. I then copied the selection and pasted it to make a new layer. Saved the file in layered PSD format.

In Premiere Pro 1.51, I imported only the feathered layer as footage.

My test image overlaid perfectly with the automatic alpha channel applied by Premiere.

[Craig Howard]

The problem is probably in the edges you are creating by your paint technique.

Alpha mattes in PremPro work very well - eg the Tiler uses alpha channels. I use them from AE all the time (logos etc)

The microphone fix is simple and fast. Use a garbage matte.

Create a frame that is clean of the microphone and put it on a new layer Draw a four point garbage matte on the clip where the microphone is.

[M***@adobeforums.com]

David - thats excatly what I'm doing - but when I look closely I get a thin dark line around the key edge.

I know there are other ways of fixing this with garbage mattes - but sometimes I need to do very complex things where an image matte is much better.

The mystery continues!