Recent discovery -- maybe everyone else already knows this trick

Moderator: jsachs

Post Reply
jsachs
Posts: 4203
Joined: January 22nd, 2009, 11:03 pm

Recent discovery -- maybe everyone else already knows this trick

Post by jsachs »

I recently stumbled across a way to bring out colors in washed out highlights in images, namely to darken them using the HSL color space. While I always realized lightening images in HSL tending to wash them out, it didn't register that darkening them does the opposite. For the next release, I have updated Transformations.pdf and Curves and Histograms with examples.
Darkening HIghlights.jpg
Darkening HIghlights.jpg (137.94 KiB) Viewed 2458 times
Jonathan Sachs
Digital Light & Color
pierrelabreche
Posts: 414
Joined: January 29th, 2019, 11:47 pm
What is the make/model of your primary camera?: Nikon Z8

Re: Recent discovery -- maybe everyone else already knows this trick

Post by pierrelabreche »

Very interesting !
Bob Walker
Posts: 78
Joined: April 25th, 2009, 9:08 am
What is the make/model of your primary camera?: Canon R5
Location: Los Alamos, New Mexico
Contact:

Re: Recent discovery -- maybe everyone else already knows this trick

Post by Bob Walker »

Yes! Yes! Way way a long time ago, before the three-zone adjustment transform was invented, there was a recipe someone (den?) posted for manually doing that, involving making three masks (shadows, midtones, highlights) and then using the brightness curve to manipulate those brightness zones to taste. I do bet it was one of den's magic tricks.

For shadows, we would lighten in HSV mode, midtones in HSV, but darken highlights in HSL, producing what Jonathan just reminded us of. It works like magic. Does the three-zone adjustment use HSL for highlights? If not, maybe a good idea.

I used to follow that recipe so often I could almost do it in my sleep. Now I am old fat and lazy, and the three-zone works good enough. But I will darken highlights in HSL still, for those images that demand it.

Thanks for the reminder!

Bob W
Charles2
Posts: 225
Joined: November 24th, 2009, 2:00 am
What is the make/model of your primary camera?: Fuji X-Pro 2
Contact:

Re: Recent discovery -- maybe everyone else already knows this trick

Post by Charles2 »

For comparison, this is the result of using Raw Therapee's Chromaticity-by-Lightness curve to raise chromaticity near the high end, followed by its Lab-L curve to darken the high end. (Obviously, I worked on the Original Image and left the label. I had RT output an sRGB image.)
HSLmodRT-b_crop.jpg
HSLmodRT-b_crop.jpg (39.94 KiB) Viewed 2450 times
jsachs
Posts: 4203
Joined: January 22nd, 2009, 11:03 pm

Re: Recent discovery -- maybe everyone else already knows this trick

Post by jsachs »

Bob,

Just checked and I was not using HSL to adjust highlights in 2- and 3-zone transformations. For the next release, you can choose which to use via the Settings menu -- old scripts default to HSV for compatibility, but the default is HSL for new transformations.
Jonathan Sachs
Digital Light & Color
Bob Walker
Posts: 78
Joined: April 25th, 2009, 9:08 am
What is the make/model of your primary camera?: Canon R5
Location: Los Alamos, New Mexico
Contact:

Re: Recent discovery -- maybe everyone else already knows this trick

Post by Bob Walker »

Super!
Post Reply