I have come across this issue twice now. A client will send me an ad (pdf) created with inDesign. The copy has an outline turned on, the line size is set to 0, therefore invisable. When this happens you cannot see it on the pdf, but when it is sent to be printed the insides of the letters are filled in, but usually only on fonts that are less than 14 point. Not sure how I found this, a fluke for sure. Once the outline is removed the problem goes away. Just thought I would share.
Can you post some photos please?
Sure the first one is what the client sent to me, notice the insides of the letters are filled in.
The second is a snapshot of the Swatches panel noting the outline.
Your screenshot has the headline copy selected and shows that it has a stroke applied. However, the headline does not appear to have any problem with filled in letters. It is the body copy that has that problem. Can you show the color specs and any other possible information about the copy that actually has the problem?
I believe what the questioner is saying is not that the text has been converted to outlines but rather that there is a zero point stroke of black applied to the live text. They are saying that the problem is being caused by this unnecessary applying of a stroke with no weight.
I'm guessing some of the letter insides are accidently filled with a screen of overprinting black, you would not see this when the PDF is viewed in Acrobat if the view overprinting preference is (correctly) set to Always because the green background already has a 30% tint of black. The printer may be removing the overprinting when processing the PDF and causing black tint to replace the green background in some of the letters, note that not all of the small letters are filled in. The error should appear in InDesign when overprint preview is not used and in Acrobat when the view overprint preference is set to Never.
Even on the small letters that are filled in, it's totally random: e.g. not ALL of the lower-case "a"s are filled incorrectly.
If that copy is indeed live text with the same specification, it should have been all or nothing.
I'd say it's a RIP error at the printer's end or a corrupt font.
Can you upload the original PDF for us?
It does seem the printer has some setting that is creating the problem. Having a stroke should not give the effect you are seeing. If you are recieving PDFs to place it is good practice to preflight PDF files before placing them in InDesign. Gwg.org have preflight profile for magazine adds (from 2015) that are in AcrobatPro. You can create a hotfolder or droplet to preflight adds. using these.
I notice it is not on all counters you get this, so it could be the way that the characters are drawn, and you may find it is more common in some fonts than others. (It can be the font designer that made the stroke in the wrond direction.)
I'm curious what happens if you open the PDF in Photoshop as a CMYK document (essentially using PS as a RIP)... i.e. do the weird counters show up there?
Okay... I still believe this is a RIP error.
Did your printer provide any sort of proof before this went to press? and did this show up then?
Whether or not the errant 0-width stroke has anything to do with it is impossible to determine, but it's the prime suspect. That being said, it certainly doesn't need to be there so ask your client to fix that issue (Is it the same client every time this happens?). You might want to create your own preflight fix-up to find and remove any 0-width strokes in future PDFs in case they forget.
Background: Even with a "0" width, a stroke will always render at least 1 pixel. e.g., I rendered it in PS at 1200 ppi and the attached is the result. You can also see this on the screen in your ID file: If you make the fill "None" but leave the stroke, then zoom in, you will see a 1-pixel line no matter what size. (If you want some real fun, turn on GPU on a Mac! see second attachment!
It still might be worth submitting this as a bug, as InDesign should just probably say No if a 0 width stroke is applied. 🙂