jpeg Compression Quality

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I just purchased a Fujifilm MX-1200 and have been experimenting with the 3 Quality options: Fine, Normal and Basic. I have compared pictures taken at High Res (1280 X 960) in both Fine and Basic quality and cannot see any difference in quality. Even when I magnify them. I also have compared the sample images in the camera review IR web site and also cannot see any difference. This includes the Musicians, Dave's box and the test pattern. What am I missing? What should I be looking for? Saving images in Basic mode packs a lot more images into memory.

-- Bernie Hellrigel (hellrigel@radstone.com), January 27, 2000

Answers

print them out 8 X 10. Look at areas of high contrast and detail.

-- benoit (foo@bar.com), January 27, 2000.

In addition to the things benoit mentioned, look carefully at straight, diagonal lines.

-- Steve (milwaukeechrome@aol.com), January 27, 2000.

You have stumbled across one of the dirty little secrets of the TIFF format snobs. Jpeg is made to produce a compressed file size that will not show any artifacts at normal viewing. Point 1: Critics of Jpeg ALWAYS try to gt you to blow the picture up, either on the screen or by printing and try to get you to look in specific areas to hunt down defects. Frankly, if you have to go to that much trouble, it isn't worth the search. Point 2: Jpeg was designed to work best with natural scenes and so another thing the critics try to do it get you to focus on hard edges or lines which tend to show signs of compression faster than other surfaces. It is nothing wrong with the JPEG that you may see fuzzing at these hard intersections. Still, you may need to zoom in on the actual edge to see it...back to point one!!

-- Robert Maclellan (rmaclellan@buffalo.com), February 10, 2000.

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