keying problem premier pro
 

This sequence worked fine last week.

But now I'm having a problem keying graphics over a background. The background turns green. if I turn off the layer I'm keying, the background becomes visible again.

In one area I reduced the dimensions of the graphic, and that fixed the problem. But I have another area using an even smaller graphic and it still won't key.

I think it's a memory problem, and I've run into it before. but I can't remember what I did last time to fix it.

Do I have a memory setting allocated wrong?

Thanks

added: I found this info on the Adobe Premiere Pro user to user forum http://www.adobeforums.com

Why are my stills showing up as black or green?

Some people experience this when putting a large number of stills on the timeline. It is an inconsistent problem and difficult to reproduce. The following are suggestions some people have reported to improve the situation:
Make sure the color depth of the stills is 32 or 24 bit. If one doesn’t work try the other.

Reduce the resolution of the stills. Large images often cause the problem. If you are not panning/scaling the stills, convert them to the same size as your project frame size.

Convert the still files to a different format. Different people experienced success with different formats.
creig bryan (http://www.adobeforums.com/cgi-bin/w...b4c9@.3bb4870a) says:

My posted but as I know of, yet untried by others) solution is to lay any clip (usually black video) in a track above the green/black stills and set the opacity on that clip to 0. I've now found that I can also eliminate the problem by rendering the pix clips in small chunks.

kcmoore11 (http://www.adobeforums.com/cgi-bin/w...70f9@.3bb84a39) reports that increasing the pagefile (swapfile) size resolved this problem. (See Windows Help and Support for instructions.)
Mike Morrell (http://www.adobeforums.com/cgi-bin/w...b6a2@.3bb4870a) says:

So I loaded PP1.5 on another machine (workstation #2), copied the files to its drive and repeated the process. Voilà, this time PPro works fine and there are no green stills. I also copied the prproj file from workstation 1 and tried it and it works fine on workstation 2 as well. This does tell me that there is some workstation specific setting or hardware that is conflicting with PPro 1.5 and it is not simply a PPro 1.5 bug.

Mitch411 (http://www.adobeforums.com/cgi-bin/w...2a1d@.3bb8cffe) said:

The other person that I mentioned previously has resolved the problem. In that instance the black video after rendering resulted from a bad connection to the IDE scratch disk. The clue for her was that when she attempted to play the rendered media files with Windows Media Player, she got an I/O device error message. When she switched the scratch disk to a different drive, no more problems.
I'm not certain if the problem was with the drive jumper settings, a bad IDE cable, daisy chaining through a slow device, or something else. Anyway, it's something for you to look at.

solution discovered!
 

My background was an oversized graphic that was zoomed in and panning from left to right.

After setting this up last week, I had trimmed the head and the tail of the graphic, which eliminated the keyframes, so apparently the computer didn't know what to do with it.

I reset the keyframes and everything works fine again.

Thanks for all your help ~ NOT! :)