Saturday, May 17, 2014

Matching skin tones for a Kodak Moment

Every now and then I've seen posts asking how to duplicate the look of a favorite film. I've played around with the idea myself with some occasional success.  Perhaps my most successful attempt was back in ancient years--my Photoshop days--where I exhibited an image that duplicated the National Geographic look of the 1920s and 1930s.  A bit of a hassle as I remember where it took several tries before what came off the print shop's Fuji Frontier machine look like what was printed in the magazine. A learning experience and my first attempt at color management.

Now we have RT with CIECAM . The tutorial is about duplicating what the 1950s ads in National Geographic called a Kodak Moment.

Why am I working on a jpg, Raw's poor and looked down upon cousin?  Because there are a lot of  jpgs out in the world, including a several year collection backed up on my computer. Call this a gentle reminder that RT is also one of the finest jpg editor around.

This image is from Charlotte's kindergarten dance recital. It was taken flashless and handheld with a point and shoot back when ISO400 was the ultimate in digital sensitivity. So it is nowhere near as crisp and noise free as an image I would take today. But it has family significance.

When Charlotte moved on to first grade she dropped out of dance because it was no longer just fun and play and had became real work learning real dance moves. But now that she is an almost seventh grader going on high school junior she has changed her mind. Her summer vacation will be afternoons of private dance lessons followed by several weeks of 8 to 5 dance camp. With weekly  recitals that I will immortalize in pixels and  then combine with the highlight of this recital to make a photobook or calendar for mom and the grandmas. Early Xmas shopping on steroids

Pass one was standard ISO high corrections to.brightened and cleaned up the image.

Pass two added an CIECAM tone curve to lighten the girls faces without washing out their costumes. Of the two curve choices the Lightness curve was stronger than the Brightness curve

Pass three was to use the  'All' algorithm to fine tune the facial tones of the image to match those on the cover of the Kodak pamphlet.  This wasn't done with any great science; just moving sliders around until the tone match looked reasonably close. Nor was this a challenging image since I was only working with one critical tone. But it does demonstrate a workflow.

 Converted with RawTherapee  which  can be found at

Thursday, May 15, 2014

Mini Workflow Spot Color

The original image of a couple kids being photographed by their mother.

All colors except for blue are desaturated using the saturation curve of the HSV tool.

Fine tune in CIECAM using the JS Lightness and Saturation algorithm.

That's it folks.

But, of course, with RT editing nothing is ever finished. So here is the new stuff you can create when you switch to the all algorithm and start draggin' them sliders around.  The hidden artist titles this 'Cindy's Nightmare - Do you have to tell wicked step moma you caught me sneaking out to the Prince's Rave?'

Main points
The hue slider gives a full range of of colors
When  ISO6400 noise is all the same color it becomes artistic texture. Fine tune that with the Noise Reduction Chromatic sliders
The other CIECAM sliders work pretty much as expected but with different intensities. For example the Q brightness slider is stronger than the L lightness slider and at 100% washes everything except the colors to white

Happy exploring your own Hidden Artist

Processed with RawTherapee  which can be found at