Right-click on the still on your project timeline and select Field Options/Flicker Removal.
I do this as a rule with all of my photos. Flickering is not a problem with all photos, but setting Flicker Removal is good insurance against it.
Criminy. You'd think I would have noticed something like that.
Thanks, Steve, I'll give it a try...
Another follow-up question: When I exported, I accepted the PRE defaults of "Bitmap" (.bmp). I later noticed I could have selected other formats (TIF, GIF, etc.). Does it really make any difference, either with respect to quality or my jittery-ness problem, which format I choose?
Not at all. Although GIFS generally don't have the color range of the other formats.
Well, good news! I got it working. My freeze frame is now rock-solid!!
I did the Flicker Removal - that's a good tip to know. It's now on my "cheat sheet".
One odd thing I noticed was when I opened the "freeze frame" .BMP that PRE had generated, the .BMP itself had interlace lines in it! Obviously I didn't want that, so I did the freeze frame again. But this time, the exported .BMP was fine (no interlace lines).
I don't think I did anything differently. About the only thing I can think of is that currently the clip is Time Stretched and Frame > Blended. Maybe when I did the original freeze frame (that gave me an interlaced .BMP) it was either not Time Stretched and/or not Frame > Blended?
I always recommend, when you save a Freeze Frame from a video project in Premiere Elements, that you deinterlace the picture and set it to square pixels, 640x480. That will give you the best results.
In version 8 you need to create a Share preset for still at these settings. (The settings are no longer available from the Freeze Frame menu.) But in previous versions of the program, if you click the Settings button after choosing to export your Freeze Frame as a photo file, you'll find an option screen where you can make the settings for frame size and pixel aspect ration. The Keyframe and Rendering page has a checkbox for setting the picture to Deinterlace.