JPG vs. RAW comparison

[Doug Nelson]

Excellent side-by-side comparisons of identical images, one JPG and one RAW, before and after adjustments.

http://www.luminous-landscape.com/tu...-follies.shtml

[patriciakay]

Hello Doug...

What an interesting comparison.....I have just a few weeks ago started shooting RAW and i am really impressed with the quality of my photos now...so much more control on the final output and of course perfect for doing HDR!!!

Thank you for the link..looks like a lot of interesting reading there!!!

Patricia.............

[duwayne]

I have done several of these experiments myself trying to develop a set of guidelines and/or criteria for when to use RAW and when to use JPEG. I am not starting with the assumption that one is optimum for all conditions.

At the bottom of his page, the author states "As so frequently happens on the Net, people bring their own biases and preconceptions to what they read." He should have also included ".......what they write." I think all he has proven is that if you're going to take a badly exposed photograph you better shoot it in RAW so you can use the one-button fix in Lightroon.

Attached are two images (JPEG on left, RAW on the right) taken with a 10.2MPixel Nikon D80 at ISO 100 using dual RAW+JPEG Fine capture. They are magnified 800% to actually see the individual pixels. No image modifications were made in RAW converter or Photoshop. I was actually looking for JPEG compression artifact. Comparing pixel to pixel the only difference I found was due to the noise left in the RAW file.

My conclusion is that there are no JPEG artifact created when using the Fine setting in the D80. I think it's like using a very high (12) quality setting to save JPEG filew in Photoshop. The only compression is of adjacent identical pixels. If this in the case, no information is lost.

I would like to see experiments other have done.

[CJ Swartz]

Shooting raw can produce a better image if a person is shooting at a higher ISO (400 for some cameras, 800 - 1600 for others) when the camera's noise reduction algorithms are so strong that they mush the image. From the reviews I've seen at DPreview, the Nikon 80 does not suffer from this problem, but many cameras do, including some DSLR's. DPreview's DSLR reviews now include examples of images shot in JPG and raw format and generally shows that any apparent differences in image quality at higher ISO can be attributed to camera processing differences which can be avoided by shooting in raw and using a good raw converter.

Operator error is another factor that motivates some to shoot raw files more than straight JPG - I've read a number of stories about folks downloading their images to find that they had forgotten to change the white balance or ISO -- when shooting raw, those memory lapses are easier to fix. That is probably not a major factor for lots of people who don't make adjustments between shoots.

My Fuji 5200 is well known for having an over-zealous noise reduction algorithm, but I can shoot JPG at 100 ISO in good light with no problem. When shooting 800 ISO, I usually shoot raw and believe that my own adjustments work a bit better than the in-camera processing.

duwayne, you may never have any need to shoot raw.

[duwayne]

Thanks for the reply CJ - I have done the same type of test up to ISO 1600 using outside shots. Same results - slightly less detail but more noise in the RAW. I ran a noise filter on the RAW file to reduce the noise to the level in the JPEG and the detail was also reduced to the level in the JPEG.

From looking on the web, I think there is a lot of differences between cameras. I started out shooting RAW because everyone said I should. I am now down to less than 5% RAW. It's only under special conditions that I use RAW+Fine JPEG "just in case". I rarely use the RAW file.

[pixelzombie]

RAW gives such a higher quality that i'm surprised more people don't use it, but if jpeg is good enough for your needs then by all means keep using it...