Spatial denoise of DSLR raw

[Terka]

Can images like high 12800 iso D800 be denoised? Decreasing resolution/blurring is ok.
http://s23.postimg.org/z1hhxf2jv/nikond800_iso.png

[yup]

Terka!
I think Non Local Means can solve problem for denoising, need only tune parameter. Try Ximagic denoiser (work with ACS and Gimp).
yup.

[lisztfr9]

For the Gimp there is a tutorial using non-linear filter (nl filter). Also you can applied this filtering through a mask, there is a discussion on Flickr explaining that.

There is chroma noise too, so... i tried once to denoise my raw files, the best tool is your raw converter coming with the camera.

On the Fujifilm x10 now they take 4 images to recompose 1 single with relative low noise, imho it's a very good idea.

[Yellow_]

Darktable, open source, offers camera sensor noise profiling and removal in raw. Many camera noise profiles have already been created and camera model is auto detected at raw import. However its only available for Linux & Mac. Its also offers OpenCL.

[Terka]

Thank you for suggestions. I mean use avisynth filters using Fritzphoto. On really high iso samples appear group of pixels eg 8x8 pixels, that create fake details that are difficult to remove. Compare the blue gradient iso 100 vs iso 12800 under the letter "t" (last character of sign "..ofot")

[lisztfr9]

Avisynth, as the name suggest is not suitable for that particular task, and fritz pro isn't aimed for that either. You will be able to use a general purpose spacial denoising filter only.

Denoising, i mean converting from raw to jpg is a very complicated task, first of all it involves procedures only relatives to you camera (demosaicing...), it's sensor, even barrel and concussion distortions.

But you can apply a denoising filter through a mask with Gimp, for example preserving dark parts (as your deep blue artifacts). Gimp as at least 2 filters for that, and the nl filter for example will keep details between pixels when contrast is low, etc.

Basically, duplicate your image, apply a denoising filter, and apply it through an inverted mask, so the filter will work only on low light..

http://registry.gimp.org/node/4235


1) From raw to jpg it's a long and abrupt path, involving more than can be thought, -> There are more things in heaven and earth, Horatio, Than are dreamt of in your philosophy. - Hamlet (1.5.166-7)

2) Gimp is you friend, masks allowing you to control the result. Or your raw converter (i guess there are some free too), Gimp can open some raw files too.

[sh0dan]

If you use Linux, Rawstudio implements the fft3d-filter de-noising and sharpening algorithm, with a similar functionality to 'limitedsharpen' added on top. Obviously it is only a 2D version.

Almost all code was re-written, since ff3dfilter was very inefficient in terms of multithreading. All paramters have been combined in to a single "luma denoise" and "chroma denoise" and "sharpen" values.

[Terka]

sh0dan thank you.

[Terka]

one more thing - which resize method to use to reduce the noise by resize?

[Lyris]

It's not Avisynth, and it's not open source, but so far I haven't found better spatial filters for this task than the ones that come in Adobe Lightroom.

[Motenai Yoda]

I think best filter for photo denoise is nik noise reduction, but is only for ps and not free
Imho LR and Topaz ones do a sharpen after denoise...

also working hard in ps with channel maskering, filtering and switching (cmyk and rgb channels are somehow compatible) can do many times better than an automatic filter