Sunday, November 27, 2011

Comparing JPEG Compression Quality - Nikon vs PhotoShop

The Gory Details

Was curious as to how Nikon's D50 in-camera JPEG compression compared to that of PhotoShop Elements 6 (PSE6). According to the D50 manual, Nikon's "Fine" jpeg compression is 1:4 and their "Basic" compression (i.e. smaller file size) is 1:16. I was thinking of using Nikon's "Basic" compression quality to save a few steps in PSE6 when making images for auctions or quick forum posts. So, I took two identical shots of the trusty Citizen Wingman, with the only difference being the selected image size: everything else set manually, and no change in lighting. Here they are both, "Fine" image on top, click either one to see it's full-size image.

The above are the images as delivered by the camera without any editing other than cropping and re-sizing to act as clickable thumbnails. As you can see, they look much of a muchness. However, at the pixel level, a different story unfolds . .

Above is the logo from the Fine image, blown up 16X time fullsize in PSE6 (but not resized, I used Windows screen capture to get the image). Not bad, really. The Basic image detail below, however, came as a bit of a shock! (scroll up and down to compare the two).

The color rendition of the logo is pretty poor and there may even be an artifact or two to be seen. Gone is any notion of cutting out jpeg compression from my auction image workflow in PhotoShop!

Next, out of interest, I used PSE6 jpeg compression (level 7, whatever that means) on the Fine image and, for a somewhat smaller resultant file size than that given by Nikon's "Basic", got this:

Pretty good, I thought. So, at least in the compression department, PhotoShop beats Nikon handsomely, IMHO.

Best regards, xpatUSA

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