Thursday, June 25, 2015

Wavelets and Lorde

After a major professional photoshoot--the cover and feature article in Australian Vogue--Lorde, the New Zealand songwriter and singer of Royals and Pure Heroine fame--posted a selfie on Instagram. So far 148 thousand of her 2.5 million followers have loved it

My 12 year old granddaughter didn't love it. Too, too noisy. So fix it. grandpa.  (Got her RT trained since she was three and I gave her a big girl camera that took pictures of her feet and her cat and herself in a mirror)

Grandpa's two minute fix. Far less noise coupled with slightly more sharpening. The S/N was measured using ImageJ


The idea is to remove as much noise as possible and not worry about the sharpness. So there is nothing magic about the  91.59 luminescence. Could have been 100% if this wasn't a two minute fix and I had been paying more attention to the GUI fit on the screen.


Increasing the edge sharpness strength to 34 restored the original sharpness. Some small artifacts showed up as bright spots at 300% magnification. Using the denoise section of the tool removed most of them. I should note that the  tool is still being debugged and improved so these minor artifacts may not be a problem in the next build.

Final note. The denoise slider numbers in the history panel are the correct numbers. The slider settings  on the right  are the defaults when I set the sharpening strength.

To download the latest version of RawTherapee go to
 It's is open source, works great and will be forever free