This is based on my own recent experience renewing my Irish passport. My first photos, taken at the local Walgreens (a U.S. pharmacy chain) were rejected. They may have been fine for a U.S. passport, but they did not meet the current Irish standards. That was about $10 down the drain. I did some searching, found a tutorial online and decided to give it a go myself.
My second pair of photos was accepted. Here's the recipe that worked for me.
Modern digital cameras are ridiculously good, but nevertheless it's not trivial to get the picture right. I found the lighting to be the biggest challenge. You want to avoid harsh light and visible shadows. Here are some hints.
I used the GIMP, a free program available for Linux and (with possible limitations, MacOS and Windows as well). Any decent image manipulation program should be able to do the job as well, but I'll assume GIMP is used here.
You want the number of pixels between the top of the head and the bottom of the chin. (Zoom in so as to show only what you need to see to complete the measurement.)
In the GIMP, the measurement tool is available from
the Tools menu or via the keyboard shortcut,
shift-M. It helps to hold down the
key while measuring to keep the measure aligned to the vertical.
The measurement appears at the bottom edge of the image window,
to the right of the zoom level.
To the left of the zoom level is a dropdown menu that allows you to
choose the measurement unit — you'll want that to be pixels
This takes two steps:
The following calculator does the calculations, assuming Irish standards (head height 34mm; photo width 37; photo height 49mm).
The aim is to select the exact rectangle to get the right proportions in the printed result. The GIMP has a rectangle select feature that does what you want.
Rif you use the keyboard shortcut.
xheight) below that.
Actually using the select tool should be relatively easy.
ctrl-Cto copy the selected rectangle to the clipboard.
Depending on how you took the picture, it may be acceptable as-is, in which case, skip this step. In my case, the background was a bit dark in the image and needed a bit of brightening. Here's how.
ctrl-Ato select the whole picture. Hit
ctrl-Cto copy it to the clipboard.
Choose a size that's convenient for you to get printed. If you want to use your own printer with photo-quality paper, use the size of that paper. Otherwise, use a size that you can print in a shop. (I chose to use 4"x6" because that's the most common size to print in the U.S.) Specific instructions for the GIMP are below.
On a 4"x6" sheet there's just enough space to fit six images, two in each row. It's up to you how much time you want to spend, but in any case, allow some space (at least a millimeter or two) around the outside edge.
Copy the final image file to a USB stick or flash card and take it to a shop that does digital prints. (Ironically, in my case, the same Walgreens that failed me before was the most convenient choice.) Print the size you chose earlier (4 by 6 inches in my case).
That's it. You just need to carefully cut out two of the images for the application. Use the measuring slot on the instruction sheet to ensure that the photo is acceptable before mailing.