Having a prepared photo printed at a shop is usually the best combination: proper photographic paper, accurate colour, a few minutes' wait, and a surface that takes a pen where an authority requires an endorsement.
The risk is that photo kiosks and lab printers are built to print pictures, and pictures are expected to fill the paper.
The problem
A 4 by 6 print from a 3:2 camera file fills the paper exactly. Hand the machine anything that is not 3:2 and it has to decide: crop the image to fill, or shrink it to fit and leave white margins.
Both are wrong for a document photo. Cropping cuts your carefully placed head out of position; shrinking makes the printed photograph smaller than the specification.
The solution: order a sheet
Do not upload a 35 by 45 mm image. Upload a sheet - a file already laid out at the paper's own aspect ratio, with several copies of the photo positioned on it at true size and cut marks around them.
A 4 by 6 sheet is 3:2, which is exactly what the machine expects, so it prints edge to edge with no decision to make. The photos inside it come out at the size you laid them out at.
Then cut them yourself.
What to say at the counter
- Ask for a standard 4 by 6 print of the file, as an ordinary photo print.
- Ask for no cropping and no auto-enhance. Auto-enhance adjusts colour and contrast, and can shift a carefully set background grey.
- If the terminal offers "fit" and "fill", choose fit.
- Avoid the "passport photo" button on the kiosk - it re-crops your image to its own template, undoing the work.
Check before you leave
Measure one photo on the sheet with a ruler. It takes a moment, and a reprint is trivial while you are standing there and expensive once you are home.
Check colour too: if the background was meant to be light grey and the print looks warm or blue, auto-enhance was probably on, and a reprint with it disabled will fix it.
Where a shop is required rather than optional
Canada requires the photographer's name, address and the date on the back of one print; Australia requires an endorsement. Both effectively mean a commercial print. Some counters will apply their details to a photo you brought in; some will only do it for a photo they took. Ask before paying.
IDShot produces sheets sized for 4 by 6, 5 by 7, A4 and Letter with cut marks, so what you hand the counter is already the right shape for their machine.