Digital Light & Color

A user of a Panasonic GF1 with 20 mm lens posted this pointillistic (oversharpened?) image of trees in Central Park. It's a 16MB JPG, which is strange for a 4010 x 3008 image.

http://farm3.static.flickr.com/2599/412 ... c3f6_o.jpg

I opened it in Picture Window Pro and discovered that with the slightest tweak of color or brightness, even brightness level, it falls apart. The leaves turn into a mess of chaotic little spots.

Oddly enough, the Fast Stone viewer program can brighten or darken it gracefully. So can Raw Therapee, which the EXIF says was used on the image.

I don't expect PWP to work with everything wrapped in JPG format, but I wonder what is it about the image that throws off PWP in particular.

Well, I guess it is the preview window, a quick and dirty rendering at reduced sizes. So either zoom in to 1-to-1 preview, or just Apply to see the proper result.

Perhaps you are missing the importance of having a transform editing "Preview" view that is free of anti-aliased artifacts when doing serious image editing... I personally find the non-"anti-aliased" Preview view at 1:1 invaluable.

In another thread JS provided this explanation... ...

image windows are anti-aliased and preview windows are not. To anti-alias preview windows would slow down previews considerably, effectively defeating the purpose of preview. If you preview at a zoom factor of 1:1 or greater anti-aliasing is not an issue and this is what you need to do to preview sharpening, etc.

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