Last year we worked on a book with around 1500 of photos and other illustrations. Picture files can take up a ton of storage space and the quality of the photo can be affected by the file format as well. Knowing the right file format to us is important in ensuring we have the highest quality image that is needed.
Jpegs
Jpegs are probably the most common type. These are compressed files, making them smaller and therefore easier to upload onto the internet or send in an e-mail. Lossy compression is used with jpegs, meaning the file will lose some of its image data each time it is saved. The more compression applied, the more data is lost, making this a bad option for editing but a good option for general personal use. Digital cameras are generally set to save images as jpeg files, so most of the modern images that we work with here have to be converted to tiff.
Tiffs
Tiff files are generally the standard for publishing or printing. These files can either be compressed or left uncompressed. When compression does occur, it’s in a small amount so as not to lose any image data.
Although tiffs seem like the optimal file type, for everyday, non-publication use, jpegs are probably the better choice. Tiffs take up a lot of storage space compared to jpegs and aren’t as easily uploaded online or sent via e-mail due to their large file size.
Psd: Our New Choice
At the InDesign seminar Ariane and I attended last fall, our instructor spoke of the benefits of using native Photoshop (psd) files instead of jpeg or tiff. Tiffs tend to be fairly large when their layers aren’t compressed, and psds can be saved without the bulk. We have started experimenting with this type of file in our current projects and so far it has been successful.
The Results
For best printing results, saving the file as a tiff first will avoid multiple compressions compared to saving it as a jpeg. Definitely do not compress the image more than once, as multiple compressions degrade the image. At Capital A we accept all of these file formats, as long as the resolution is high, giving us a quality image to work with.