I need to include png images of text in a photo book, but I don't know how to achieve the best quality. Are there any general guidelines?
For example, should I use a DPI above 300 and let the printer handle any downscaling needed? Is output sharpening advised?
The book will be printed on matte photo paper by a photo lab, but I don't know what print process will be used.
Background: I'm using the photo lab's own software to design the book, as I don't have the software or knowledge to create a pdf where I could include vector text.
Note that I do understand the purpose of DPI, and that rasterised text is not ideal. My instinct is to increase the resolution of the text image at fixed physical dimensions, but I'm unsure if there are any hidden downsides to that (e.g. in supplying a higher DPI than the printer is capable of) or if anything else should also be done.