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Old Sep 29, 2010, 7:20 PM   #221
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Martin,

Is there any difference in using your package to increase local contrast and using an unsharp mask ? The effects look quite similar and wiki says:

"Unsharp masking may also be used with a large radius and a small amount (such as 30–100 pixel radius and 5–20% amount[5]) which yields increased local contrast, a technique termed local contrast enhancement.[6][5] USM can increase either sharpness or (local) contrast because these are both forms of increasing differences between values, increasing slope – sharpness referring to very small-scale (high frequency) differences, and contrast referring to larger scale (low frequency) differences."
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Old Sep 30, 2010, 12:55 AM   #222
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USM is a fast but coarse approach because it uses a simple circular area. Mine is mapping the detailed edges down to every tiny leaf or strand of hair so gives a much more precise result. Quick comparison:

Original/USM(radius 50, strength 20%)AutoHDR(Detailed)

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Old Sep 30, 2010, 4:29 AM   #223
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Also worth noting the difference USM has on the histogram: For the same example as above, AutoHDR (bottom histogram) has extended the range used by every part of the image and the individual histograms for the sky and foreground now overlap. The 'detailed' preset I used affects highlights more than shadows so you can see it's affected the top end more than the bottom but it hasn't lost any detail. USM's unsophisticated impact on the other hand has led to clipping of the histogram (middle histogram) and loss of detail in the shadows. If the original histogram (top) had extended further towards the right then USM would have clipped the highlights as well.

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Old Sep 30, 2010, 12:03 PM   #224
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Very nice detail to let us chose to add or not your watermark. Thanks.
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Old Oct 1, 2010, 6:10 PM   #225
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Please try v1.119 if you haven't downloaded it yet. I've just spent ages tuning the code and have finally got rid of the last bit I really wasn't happy with. The results are looking pretty good from my testing so far
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Old Oct 1, 2010, 7:11 PM   #226
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Thanks Martin. I use Sagelight 48 bit editor and unsharp mask doesn't clip any of the histogram. To get similar effects to yours I need to brighten the shadows as well as use unsharp.

Photo-Plugins have a free local contrast enhancer photoshop plug-in (that works with Sagelight)
http://www.photo-plugins.com/Plugins...ncement-2.html
... however from what I can see it doesn't do anything significantly different to unsharp mask. Am I missing something ?

Do you know what the technical differences between local contrast enhancement and unsharpening are ?

For anyone wanting a quick HDR look, your package seems a good way to go in most situations ... just as effective as mucking around with multiple exposures on scenes that don't need it.
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Old Oct 3, 2010, 4:23 PM   #227
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Hey Martin, maybe I'm doing something wrong but, with this version I'm seeing more noise and over saturated colors. With the previous versions I was mostly doing "artistic" and I really didn't need to tweak at all.
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Old Oct 3, 2010, 4:48 PM   #228
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Can you post an example? The new version should show less noise but otherwise be very similar to previous versions.
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Old Oct 3, 2010, 5:56 PM   #229
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Here they are...
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Old Oct 4, 2010, 1:46 AM   #230
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Thanks. Can you post the original as well? Or is that the original? In which case can you post the older processed version that you liked. Old versions of AutoHDR can all be downloaded from the 'History' link at the bottom of the main webpage.

[Edit] are you sure it's not just this picture which is a bit garish because of all the cartoon colours? Below is a comparison of an old version (1.94), and the new version with no smoothing in the middle and soft smoothing on the right. In the old version it ignored softer edges which gave smooth results in places but it was an imperfect algorithm which created some other noise and artefacts. In the new version it picks out everything so you can see the much more uniform noise from the original image but there is no new noise created by the program. The smoothing algorithm then denoises that if you want. The saturation looks just the same in all three.

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