JPEG Files on the Nikon D3300 - dummies

JPEG Files on the Nikon D3300

By Julie Adair King

Pronounced “jay-peg,” this format is the default photo setting on your Nikon D3300, as it is on most digital cameras. JPEG is popular for two main reasons:

  • Immediate usability: All web browsers and e-mail programs can display JPEG files, so you can share pictures online immediately after you shoot them. You also can get a JPEG file printed at any retail photo outlet. The same can’t be said for Raw (NEF) files, which must be converted to JPEG for online sharing and to JPEG or another standard format, such as TIFF, for retail printing.

  • Small files: JPEG files are smaller than Raw files. And smaller files consume less room on your camera memory card and in your computer’s storage tank.

The downside (you knew there had to be one) is that JPEG creates smaller files by applying lossy compression. This process actually throws away some image data. Too much compression produces a defect called JPEG artifacting. This figure compares a high-quality original (left photo) with a heavily compressed version that exhibits artifacting (right photo).

The reduced quality of the right image is caused by excessive JPEG compression.
The reduced quality of the right image is caused by excessive JPEG compression.

Fortunately, your camera enables you to specify how much compression you’re willing to accept. You can choose from three JPEG settings, which produce the following results:

  • JPEG Fine: The compression ratio is 1:4 — that is, the file is four times smaller than it would otherwise be. Because very little compression is applied, you shouldn’t see many compression artifacts, if any.

  • JPEG Normal: The compression ratio rises to 1:8. The chance of seeing some artifacting increases as well. This setting is the default.

  • JPEG Basic: The compression ratio jumps to 1:16. That’s a substantial amount of compression that brings with it a lot more risk of artifacting.

Note, though, that even the Basic setting doesn’t result in anywhere near the level of artifacting you see in the right image in the figure. The defect in that example has been exaggerated to help you recognize artifacting and understand how it differs from the quality loss that occurs when you have too few pixels.

Refer to the figures again. In fact, if you keep the image print or display size small, you aren’t likely to notice a great deal of quality difference between the Fine, Normal, and Basic compression levels. It’s only when you greatly enlarge a photo that the differences become apparent.

Given that the differences between the compression settings aren’t that easy to spot until you enlarge the photo, is it okay to stick with the default setting — Normal — or even drop down to Basic to capture smaller files?

Well, only you can decide what level of quality your pictures demand. For many, the added file sizes produced by the Fine setting aren’t a huge concern, given that the prices of memory cards fall all the time. Long-term storage is more of an issue; the larger your files, the faster you fill your computer’s hard drive and the more DVDs or CDs you need for archiving purposes.

But in the end, many prefer to take the storage hit in exchange for the lower compression level of the Fine setting. You never know when a casual snapshot will be so great that you want to print or display it large enough that even minor quality loss becomes a concern.

And of all the defects that you can correct in a photo editor, artifacting is one of the hardest to remove.

If you don’t want any risk of artifacting, change the file type to Raw (NEF). Or consider your other option, which is to record two versions of each file — one Raw and one JPEG.