Photoshop/Indesign CS6: The JPEG

In this post I intend to clarify:
1) what a jpeg is
2) how a jpeq's quality can be manipulated in Photoshop/Indesign.



JPEG/JPG is a very popular file format for digital photography. It stands for Joint Photographic Experts Group (that's a kicker huh?). It is a lossy compression method that can be compressed based on one's needs. Lossy compression in I.T. terms simple means it can become smaller by losing data (thus by losing quality).

When using Photoshop or Indesign one will notice a choice when exporting or saving a JPEG file. It depends on what you are using but it should look something like this:

Either in qualifying terms like 'low, medium, very high' or a quantitative scale from 0-100. Either way when choosing the size it is important to understand that choosing a lower quality will sacrifice the quality- so unless it is necessary for size purposes- DON'T DO IT!


Here is an example of a jpeg file (zoomed in at 300%) at the highest quality versus the lowest quality.

Notice the grid like pixels that are more clearly defined in the second photo. This JPEG has lost some of the data once associated with it and now shows what photographers call digital artifacts. To avoid artifacts it is extremely important when saving to maintain the highest quality standards.