Photoshop Elements >

JPEG Quality Levels

0 through 12

With Photoshop Elements, you can select a JPEG quality level from 0, the poorest, through 12, the best.

Compression

When you select the quality of the JPEG file that you're about to save, you're deciding how much compression to use.

The compression makes JPEG files smaller.

JPEG files use lossy compression.

Some of the pixels are discarded when the photograph is saved.

What's discarded?

JPEG compression is based on what our visual system is sensitive to.

We're more sensitive to contrast variations, than to color  variations.

So, unneeded color information is discarded more than contrast information.

 Again, we're sensitive to contrast variations.

But, the contrast variations we can see have to be large.

We don't see fine variations in contrast.

Let's say you have a photograph of a chess board on a picnic table.

The sky in the photograph, with many fine contrast variations, can be compressed.

The chess board, with many large contrast variations, can't be compressed as much as the sky.

The sky is high frequency variation, the chess board, low frequency.

To see the difference in high and low frequency variations, go to High Pass & Gaussian Blur Filters Compared with Step Wedges.

Which Quality Level?

Smaller files enable web pages to load more quickly, and allow photographs in e-mails to be sent and downloaded more rapidly.

Larger files are better for making prints.

If a file will be used for multiple purposes, save it with different quality levels.

For example, you could save red_car_truck as:

• red_car_truck_copy_quality_12

• red_car_truck_copy_quality_3.

The original, red_car_truck, is preserved.

red_car_truck_copy_quality_12 will be used for printing.

red_car_truck_copy_quality_6 will be used for e-mails.

The chart below shows how the file size changes depending on the quality level.

Quality Level	Original File Size	New File Size
0	31.90 KB	33.75 KB
3		46.15 KB
6		55.31 KB
9		69.72 KB
12		103.45 KB

The photographs below show the increase in quality from level 0 to level 12.

Quality Level 0 - 33.75 KB

Quality Level 3 - 46.15 KB

Quality Level 6 - 55.31 KB

Quality Level 9 - 69.72 KB

Quality Level 12 - 103.45 KB

Original - 31.90 KB