Re: The group's techniques, 2


Thomas Hurd,MD
 

Roberto, 

Thanks for offering up your image for us.

I also enjoyed and used Robin’s suggestion. In fact, I used it on the whole image, from the scratch conversion to CMYK, using fully saturated, no masking.

I duplicated the CMYK base image and then used Robin’s screen blend suggestion. Then I duplicated that layer twice to my taste for the highlights. I put those 3 stacked screen blend layers together in a group. 

Then I used a base layer duplicate on top of that and used multiply blend, opacity to my taste and more duplicated multiply layers, all for more shadows. I put the multiply layers in a group. I then decreased opacity of each group to control highlights and shadow. 
I was pretty close to what I wanted with a lot less work! So thank you Robin.

There was not enough cyan, however, so I duplicated the base layer and then blended about 20% of the yellow channel into the Cyan to give it enough weight to play around with. (Before channel blending, there was almost no cyan in the screen left arm.)

Again I changed opacity with the cyan fortified layer to get a level around C 6-8% on that red in the left arm. That was pretty close to the par image, and I am now experimenting with a curve on top of the whole stack.

It’s not all the way to the par image yet, but it’s close to it, and better than my original entries. And it just took about three minutes.

I’m looking forward to trying and experimenting with all the other techniques Dan described, as well. Although in my entries I transported back and forth between color spaces, I never thought to use ProPhoto RGB, but I will soon be trying it. The technique I described above never left CMYK after the initial conversion.

Tom Hurd


On May 19, 2020, at 10:12 AM, Roberto Tartaglione <roberto@...> wrote:


Dear Dan,
I've applied your method on more images of the same kind
and I can confirm from my point of view that is a very reliable workflow, it can easily 
be automated too. Of course, it can not solve all multiple problems of 
a conversion in CMYK, but there are many ways to finish the job.

You also offered me an important food for thought:
"A CMYK fact of life: the lighter the desired color, the worse the possible gamut mismatch. If we were doing pink flowers the problem would be much more severe, and we’d see a lot more variation in the quality of our corrections.”
In my professional life one of the harder (or perhaps The Harder) object to photographers has been Wine Rosè (although I was not involved in the Pre-press), but this is another story...

In the next days, I wish also try to experiment with another strategy: to process again my files from RAW into ProPhoto RGB instead of AdobeRGB and then to follow the same routine. It is interesting because I always thought otherwise, a few times in the past I converted the image in sRGB before CMYK to narrow the gamut before the conversion, obtaining no bad results.

I’ve also tested  the suggested  channels blending from RGB to CMYK, I think is a very successful technique that I never would have thought about, but 
I think it requires more experience, I mean it can be easier to worsen the image.
Last but not least, the tip from Robin Mark D'Rozario, can add a final touch to the image, I think
it will be useful for more than an image in my future workflow.

Once again I wish to thank Dan Margulis for focusing on this case and
to all the contributors who really helped me grow.

Roberto


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