I need to flatten my layers on a project before sending to print.
I opened the layers panel and selected all the layers but when trying to merge them it is not highlighted. Can someone help a novice?
Are you sure you're selecting primary layers and not sub-layers? I do suppose there could be some flavor of content would disqualify a layer from merging (groups created while Ungrouping Remembers Layers is in effect comes to mind), but I never merge layers so I haven't encountered that condition. I certainly can't reproduce it here now.
It could be one of those quirks that clears up with a reset of preferences.
I was told that when sending to be printed digital to make sure I flattened the layers. I have a solid color on the bottom that bleeds off all sides and then other text and art on top of it. I will save as a pdf. Could it be fixed in preflight?
export PDF as PDF X1a--that will generate a flattened PDF
There is a big difference between layers in an InDesign document and layers in a PDF file. I assume that the flattening referred to is the PDF file, not the InDesign document. (Modern workflows sent PDF to the print service provider, not InDesign documents and assets - images, fonts, etc.)
Unless you use a PDF export option that explicitly requests that InDesign layers be preserved in the resultant PDF, the PDF file has no layers at all. None of the PDF export options provided with InDesign preserve InDesign layers in PDF. Thus, layers in your InDesign document are totally irrelevant to your PDF output.
If by “layers” you are actually referring to transparency, that is a separate matter. Flattening transparency prior to the printing process at the RIP or DFE does degrade quality on output. However, if you have a Luddite print service provider that insists on no transparency, the PDF/X-1a PDF export options will flatten transparency and also ruin color management.
Thank you all for your expert information. It was a great help!