I did benchmark a camera noise profile [1]. My input files [2] go from
ISO 100 to ISO 25600, at powers of 2 (100,200,400,...,12800,25600).
To prepare the benchmarking I did the following within darktable
1.7.0+1256~g960e920:
Create a hdr out of five images at camera base ISO 200.
Create two minimal styles: WithNR (profiled denoise ON) [3] and NoNR [4]
(profiled denoise OFF).
Discard the history stack of all test images.
Select all images and double-click NoNR profile.
Export all images as PFM(float), using the NoNR profile, replace history.
Discard the history stack of all test images.
Select all images and double-click WithNR profile.
Export all images as PFM(float), using the WithNR profile, replace history.
Here comes the problem:
The benchmark results [5] show a strong increase of signal to noise
ratio for part of the images, but the three images at ISO 1600, 3200 &
6400 show only minimal or no increase of the signal to noise ratio.
On visual inspection, there was no big change in noise appearance for
this three images. Others worked better or excellent (as usual with the
very good profiled denoise module).
In darkroom mode I checked the profiled denoise image by image, and
found that the profiled denoise module is using wrong profiles for some
of the images.
ISO 400, 800, 1600, 3200, 6400 has wrong automatic selection of denoise
profile ("using interpolated from ISO 100 and ISO 12800").
For ISO 100, 200, 12800, 25600, the selected denoise profile is as
expected ("found match for ISO ...").
After selecting the matching denoise profiles manually from the
drop-down list, I get much better signal to noise ratio [5], and
visually much cleaner files.
The used profile presets.json [1] contains entries for all nine ISO
settings.
Why does the profiled denoise module partially select interpolated
profiles, even when there are matching profiles? Does this just happen
with my denoiseprofile [1], or is it happening with other
denoiseprofiles also?
Urs
[1]
https://www.dropbox.com/s/e7we55r8ru5p14h/dt-noiseprofile-20150412.tar.gz?dl=0
[2] https://www.dropbox.com/s/w8wqjm8bzsltawi/RawTestImages.tgz?dl=0
[3] https://www.dropbox.com/s/tg6izewjrcqsuex/NoNR.dtstyle?dl=0
[4] https://www.dropbox.com/s/1v6txb7b1sk82v7/withNR.dtstyle?dl=0
[5] https://www.dropbox.com/s/9y37i3ev507b1mo/Benchmark%20Results.ods?dl=0
------------------------------------------------------------------------------
BPM Camp - Free Virtual Workshop May 6th at 10am PDT/1PM EDT
Develop your own process in accordance with the BPMN 2 standard
Learn Process modeling best practices with Bonita BPM through live exercises
http://www.bonitasoft.com/be-part-of-it/events/bpm-camp-virtual- event?utm_
source=Sourceforge_BPM_Camp_5_6_15&utm_medium=email&utm_campaign=VA_SF
_______________________________________________
Darktable-users mailing list
Darktable-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/darktable-users
