Very interesting Klaus; Did some tests on contrasty high altitude mountain snow scenes and by setting the red channel to zero the 'grain' all but disappeared, further I was able to use greater sharpening and the denoise function worked exceptionally well. Very big difference!
On the same imagery the blue at zero was not so effective but I will now make some tests with other imagery and try to standardize some settings. It would be interesting if, with Saturation set to zero, the Colour Temperature somehow directly related to thy Channel Mixer settings (probably just too complicated). More work .. I probably now need to rework a whole bunch of data ... but seriously thanks again. David On Wed, 2011-04-13 at 22:14 +0200, Klaus Post wrote: > Hi David! > > On Wed, Apr 13, 2011 at 17:47, David Vincent-Jones > <[email protected]> wrote: > I am finding that sharpening of my monochrome images appears > to create > fairly heavy noise, even when done in moderation. I have tried > the > 'denoise' feature and find it makes little or no change. > > The "denoise" also functions as a noise floor for the sharpening > algorithm, so in general you should try to > > Secondly, when doing BW, you can sometimes reduce noise by eliminating > a channel that is "stretched" due to white balance, so if you have low > WB temperature, eliminate the blue and if you have a medium to high, > eliminate the red. > > I just did a few tests on high contrast, high ISO BW images, and I can > see your issue, since color noise is converted to luma noise. I will > do a few tests, but it seems like it could be a solution to heighten > the maximum value for denoise, to 150 for instance. I don't want to > set it too high, since we begin to get artifacts in some cases. > > In part this may occur since I tend to manipulate the tone > curve fairly > extensively with monochrome. > > As I understand it sharpening needs to be applied subsequent > to all > other functions ... does the program know that? > > Yes - sharpen/denoise is the last function to be applied in the chain. > > > > Is anyone out there also finding this same situation and is > there a > solution? > > David > > Best regards, Klaus > _______________________________________________ > Rawstudio-users mailing list > [email protected] > http://rawstudio.org/cgi-bin/mailman/listinfo/rawstudio-users _______________________________________________ Rawstudio-users mailing list [email protected] http://rawstudio.org/cgi-bin/mailman/listinfo/rawstudio-users
