jollydave
Although knowing the version of Premiere Elements and the computer operating system on which it is running are important, it is important to know what you seek when
you say "..produce an image file from part of my video in timeline...."
1. Do you want to generate a screen capture (freeze frame), exporting it in the sharing area/Image category as a jpeg
OR
2. Are you referring to producing a portion of your Timeline video to a disc image in the sharing area of Premiere Elements 13?
If what you want to do is related to "1" above, then full step by step details should be found in the following link
ATR Premiere Elements Troubleshooting: PE11: Freeze Frames, Single or More Than One at a Time
If what you want to do is related to "2", then there are some considerations we need to explore.
Please review, supply more details. Any questions or need clarification, please do not hesitate to ask.
Thank you.
ATR
