I have set up a project at 300 ppi in photoshop and the printer wants a 600dpi pdf. How can I do that please?
In Image Size, uncheck "resample" and change ppi to 600. This doesn't change the file in any way. Then save out a new PDF.
You need to realize that ppi is just metadata. It's not a property of the file. It's just a way to translate pixels into a physical print size. Pixels per inch. It means exactly what it says.
The bigger you print your file, the lower the ppi number, and vice versa. Print size determines ppi.
So if what the printer is really saying is that your file doesn't have the necessary pixel resolution, you can't "fix" that. You need to make a new file with more pixels.
Thank you. I need to keep the file to A6 size with bleed, therefore maybe I need to set up a new psd file.
I have set up a project at 300 ppi in photoshop and the printer wants a 600dpi pdf.
In addition to what @D Fosse said, you need to change the joboptions when saving as Photoshop PDF. The default is to save in Acrobat 5 (from 2001) and to downsample images above 450 ppi to 300 ppi. If you change the ppi to 600 in Photoshop, it will then drop to 450 if you don't also change this setting in the Compression tab.
I noticed that you said your project is 300 ppi "pixels per inch" and the printer wants 600 dpi "dots (of ink) per inch". I don't know if that is part of your question or not. You are correctly saying ppi. Most likely the printer is simply confused about terms, as only the printshop can control the output of ink to paper.
Thank you. I'm going to have to check with the printer precisely what he wants. It's a learning experience!