My sharpening workflow for base ISO mages with the new features in RT (aka extreme pixel peeping)

@nosle

@heckflosse I go, in your workflow do you also play with the contrast threshold under AMaZe+VNG4?

For my Nikon D700 the default of 20 works good. But for files from other cameras I use different settings.

Do you always use the same contrast threshold value for the three of Demosaicing, Sahrpening and micro-contrast?

If I use Microcontrast, I use the same value for Sharpening and Microcontrast. The value for Demosaicing is different.

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proposed procedure for tweaking contrast threshold in amaze+vng4 demosaicising:
First set sharpening threshold to a value, where sharpmask shows still marks in flat regions e.g. between 7 and 10. Then tweak contrast threshold of demosaicising to a value short above a point, where sharpmask doesn’t change any more. In the next step the obove mentioned procedure of heckflosse can follow.

Is a procedure like that ok?

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Yes, that’s a good procedure :+1:

@hholt It should be possible to automate the process of finding a good threshold for AMaZE+VNG4. I will try that.

If it’s possible to automate a good threshold for AMaZE+VGN4, perhaps it is also possible to use that process to automate a threshold for sharpening and microcontrast?

That should also be possible. But step by step :wink:

My first tests to find a good threshold for AMaZE+VNG4 are promising. It won’t be completely automated because the user still has to define the area where the threshold is calculated from. This will be implented as a tool like a spot whitebalance picker, means you click on a point in the image (for example blue sky) and the threshold will be calculated from the surrounding 36x36 square.

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How does one enable the sharpening contrast mask display? I cannot find any button to click on.

Hi,
Can someone explain me the colors in the mask? What they mean ??

Cheers

The button is right of the focus mask button. Currently it has the same icon as the focus mask button. That will be changed soon.

The colours are the colours of the image. They mean nothing. They are just background for the mask.

The brightness counts. Bright parts are taken from AMaZE, dark parts from VNG4

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Thanks.

It turned out that it is possible. In my current tests I get an almost perfect auto-calculated contrast threshold for AMaZE+VNG4. Almost because currently the granularity of the slider is 1 and for that reason the auto-calculated threshold may be off by < 1. Changing the granularity of the slider to e.g. 0.5 would allow to get even closer to a perfect match.

The auto-calculation is done by an iterative process which at current granularity of 1 adds only < 1 ms to the processing time. Changing granularity to 0.5 would add < 2 ms to processing time.

Now I have to make the gui part. Damn, I hate gui coding…

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It’s posts like these that get me excited :slight_smile:
While Lightroom has its hidden-behind-the-hood demosaic process, RawTherapee has more than half a dozen and they are in constant development. I can’t wait to try out the new features. It’s so nice seeing a bunch of good folks working on pushing the limits of what we can get out of our cameras.

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You can already try them out (except the automated calculation of dual-demosaic contrast threshold).

@heckflosse where would I download the appimage ? I run debian linux

RawTherapee-dev-5.4-412-gb626b4e9.AppImage

@heckflosse sweet will try out :smiley: