Preview app destroying pdfs

Hello Everyone.

I am wondering if anyone else is experiencing similar issues with the preview app and pdf documents.

At work I get tasked with printing large a1 posters and I use a Mac compared to most staff as I find it quicker for myself. I have a choice of either using acrobat, or preview to view my pdf documents that people send to me.

Acrobat I have to say is still the best pdf editor out there, considering I am not paying for it, but the company is.

People have sent tons of pdf files to print, and from time to time I preview them on my Mac. Even though the poster printer is able to print directly from pdf, if that pdf file has been previewed via the preview app, then its no longer the original pdf.

In other words, I have not made any changes to the pdf document, but because I did open it in preview, it seems to change the structure of the pdf file.

I did several test, and the files that were never opened via preview print directly in the printer via pdf, but the files that I open in preview to take a look (change nothing) and simply close, seem to make printers crash.

My conclusion is, as preview has this auto save mode, it seems to also save it self as a Mac version of a pdf. which for some reason is unreadable in a lot of cases, leaving me with no other option, but to export the poster as a jpeg just to be able to print it.

Took me a whole day or trying to figure out what was going on.

I had to change my default app from preview to acrobat for all pdf formats, and even if its slower, at least the file stays in tact.

Conclusion is not all pdf's are equal. Im the only Mac user in the office, and seem to make a fool out of myself with simple issues as such.

Has anyone else experienced this issue with preview?