Jeremy C. Reed wrote:
I have a solid color background. Then a layer above that is a pattern of repeated logos. All are selected as a group. When I choose Fill and Stroke and change Opacity to less than 100% the final PDF doesn't show that layer anymore. (Even 99% does not work.)
Xpdf shows it drawn but then it is immediately replaced with the solid background.
In inkscape itself, it appears correctly.
When I change opacity back to 100% it works again. Any ideas how I can opacity be less than a 100%?
When opacity is less than 100% a soft mask is used in the PDF file. Soft masks are something that not all PDF viewers correctly support. The PDF files created by Inkscape with opacity less than 100% renders fine in Adobe Reader and recent versions of Evince.
Generally whenever the PDF output does not appear correct you should check it with Adobe Reader as other PDF viewers sometimes have bugs or unimplemented features. This should probably be added to the Inkscape FAQ.