Hi all,
I'm fighting the high ISO noise of my A550 camera, but I still cannot
achieve the reasonable output. Even the new profiled denoise filter doesn't
help much.
Below is the example of the ISO12800 image. I do not take images on such
high ISO but it makes this problem more visible for this purpose. This
behaviour may be observed even at ISO1600 and higher. The RAW image below
is totally unaltered RAW for comparison opened side by side in dt and in
Lt. Only the base curve is applied at dt side because otherwise the image
looks very ugly and not comparable to the Lt from the visual point of view.
Link to unaltered RAW image:
https://dl.dropboxusercontent.com/u/9454436/sony_noise/raw_not_altered.jpg
As you can see the image looks almost the same in both tools. Just note the
bright red dots. The Lt shows less of them especially on the right side of
the paper Christmas tree. These red dots cannot be removed by any of the dt
denoising filters unless the image becomes almost blurred.
Now see the next image below. This shows what can be achieved in dt and in
Lt. While only activating the luma and chroma denoise sliders in Lt
produces the acceptable and (to me) pretty usable output where only some
luma noise remains, with dt I cannot achieve similar output by no means.
The most strange finding is that no one from all the denoising filters
available in dt can remove these bright red dots unless it is pushed to not
acceptable high strength producing the blurred image. The only strategy I
found to be somehow working here is as follows:
1) turn off the sharpen filter
2) apply the hot pixel filter at its maximum strength
3) set the color smoothing of the demosaic filter to maximum
These three steps do remove the bright red dots. But the image still
suffers of the high chroma noise. The only possible way to get rid of it
while maintaining the image sharpness at the level comparable to the Lt I
found is the profiled denoise set to less than default strength. But as you
can see there still remain far more chroma noise than in the Lt case.
Link to altered RAW image:
https://dl.dropboxusercontent.com/u/9454436/sony_noise/raw_altered.jpg
Because I've got to that point I didn't know what to do more, I profiled my
camera. But even though my profile seems to me to be a bit better than the
one packed with dt, it produces no visible difference here.
I would like to ask all of you experienced in fighting the high ISO noise
for your experiences and recommendations. It would be great to get to know
that the problem is in between the chair and the keyboard, not in the
excellent dt tool!:-)
If someone is interested, the original RAW image can be found here:
https://dl.dropboxusercontent.com/u/9454436/sony_noise/DSC09533.ARW
Thank you in advance for any reply!
Suni
------------------------------------------------------------------------------
Try New Relic Now & We'll Send You this Cool Shirt
New Relic is the only SaaS-based application performance monitoring service
that delivers powerful full stack analytics. Optimize and monitor your
browser, app, & servers with just a few lines of code. Try New Relic
and get this awesome Nerd Life shirt! http://p.sf.net/sfu/newrelic_d2d_may
_______________________________________________
Darktable-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/darktable-users
