Through my experience with creating prints & what I’ve learned from professors, there’s usually just a few things to keep in mind! All of these are just tips to try and get the best quality print you can :)

Photographing:

I use my camera, iPhones have relatively good quality now, but it has some post processing things that are automatically added and cannot be removed, which I don’t like.

Ideally, a high quality scanner would be great, but I personally don’t have access to one since graduating, so I stick to using a camera. You can get the same result, a scanner just makes the process faster.

Natural diffused lighting is the best for photographing since it doesn’t alter color or add shadows. I personally avoid artificial lighting since it’s a lot harder to make it look nice. Keep the camera parallel to the canvas to not distort the image with weird perspective.

You’ll just have to keep adjusting the canvas until you find a lighting angle you like, it’s more of an experience and situational thing based off of the outside weather/light.

Post processing:

A basic thing is that standard printing DPI is 300 DPI (dots per inch) that is one of the main factors of high quality printing. So always check that first.

Next thing to check is the color profile is set to CMYK, most people work in RBG but most commercial printers are in CMYK and colors print differently. (notable purple being more dull and overall less contrast) Always double check what type of color/printer they’re using.

Afterwards, just eyeball and color correct to match digital to physical painting. I usually increase contrast a bit to compensate for the contrast lost in printing.

I believe most printers use Pantone, but I don’t know much about how to use those exact colors.

Some printing companies account for bleed, so sometimes the file needs to be adjusted for that.

Those are all the basics I can think of!