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Old 22-04-11, 13:31
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Gidders Gidders is offline  
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Ok now lets go back to the basic tab and adjust the exposure.

Holding down the ALT key while moving the exposure slide will mask the image and show us when clipping start to occur. In this image clipping begins at about +0.55 but I would accept a tad more clipping and kept moving the slider to +0.8. Doing the same with the black levels shows us that black clipping begins at about 30 but again I would accept a modicum of clipping and took the slider up to +45.

Untitled-5.jpg
This gives us a nice contrasty image with the histogram filling the scale ... but what has happen to the noise levels?

Untitled-6.jpg 200% zoom
OMG ... so that's where the noise comes from

Untitled-7.jpg
Looking at whether is the increase in exposure or increase in blacks we can see by comparing to the un adjusted image in the middle, increasing the backs tends to emphasise luminance noise and increasing the exposure increases colour noise.

Untitled-8.jpg
If we then apply a modest smart sharpen on Photoshop say 150% and 0.5 pixel radius it gets even worse Looking at your image it looks at though you have been considerably more aggressive with your sharpening - I'm guessing something like 200% & 2/2.5 pixel radius, possibility to try to compensate for the lack of depth of field. This will emphasise any noise HUGELY!!

... continued in next post
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Last edited by Gidders; 22-04-11 at 13:47.
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