You will get the best result with a digital file that is formatted in full size with 180 DPI. With a lower resolution you will start to see pixels. The website will always open a digital file with 180 DPI. If you take a file with a lower or higher DPI, your file with a different size will be opened in our Webshop. The best is a full size file at 180 DPI.
It is best to save your file as a .jpg. Recommended color mode is Adobe RGB (1998). A manual that can help you prepare your files can be found here. You can upload files up to a maximum size of 150 MB. As soon as you have uploaded your file, you can see the quality of your file at the image quality.