Today’s Question: I’ve started making greater use of online printing and wonder if you can provide advice on how best to prepare files for this. For example, when I use my own printer I set the resolution to 300 ppi, but is that useful if I’m sending the file to an online printer? If I do use that resolution, it enlarges the file size often beyond what’s acceptable by the online printer. To decrease the file size I then reduce the pixel width, but does that reduce the quality of the final print? Are there other settings I should be using to best optimize an image for online printing?
Tim’s Quick Answer: Reduced resolution (as well as JPEG compression) can most certainly have a negative impact on print quality. I therefore recommend using a print service that allows you to upload large image files.
More Detail: There are two basic approaches I recommend when preparing images for online printing. My personal preference and recommendation is to resize the image and otherwise prepare it for the final output size, just as though I were printing the photo myself. The other option is to prepare the image at its native resolution and allow it to be resized by the printer.
I also recommend saving the file as a TIFF image, not JPEG. Even at a high quality setting it is possible for there to be visible artifacts when a JPEG image is printed, which are caused by the nature of the JPEG compression. I prefer to resize the image to the final output size at 300 pixels per inch, but you could also leave the file at the native size and allow it to be enlarged at the time of printing.
Some online photo printing services limit the file size you can upload, but this will not enable you to ensure optimal print quality for your photos. I therefore only recommend using an online print provider that will allow you to submit large files. For example, I have used Bay Photo (https://bayphoto.com) with very good results, and I’ve been able to upload large TIFF files for printing.
