gamut warning

[braga]

  On soft proofing in Lightroom Jeff told the Gamut warning is not important to make the final print. I'm new on print and always care about gamut warning. for me is one the best tool on LR  soft proof. I change saturation all the time for have better gamut.
  What you guys think about gamut warning in LR?.

  I print on epson p600 and luster paper 90% of the time!
  Thank's!

[Mark D Segal]

I tend to agree with Jeff on this point, and I print from an LR softproof routinely. The thing to watch for - on the display image with the softproof active is whether gamut clipping occurs when you increase saturation. This means whether you see image detail being obliterated by excessive colour. If that happens, unless you really want those very strong colours, you would normally dial-back saturation until the appropriate amount of image detail re-emerges. Using this kind of judgment is more important than a gamut warning.

[Bart_van_der_Wolf]

I tend to agree with Jeff on this point, and I print from an LR softproof routinely. The thing to watch for - on the display image with the softproof active is whether gamut clipping occurs when you increase saturation. This means whether you see image detail being obliterated by excessive colour. If that happens, unless you really want those very strong colours, you would normally dial-back saturation until the appropriate amount of image detail re-emerges. Using this kind of judgment is more important than a gamut warning.

Hi Mark,

That visual approach would only work if the display has the same gamut as the output medium/paper&ink one uses. That is very unlikely to be the case, so a proper Out-of-Gamut (OOG) warning would be a better indicator, and would still allow to judge the effect of gamut clipping, even on lower or mismatched display gamuts.

The difficulty with most OOG indicators is that they do not show the amount of OOG-ness, just that it is OOG. In that case it can help to vary the saturation and see how fast the OOG indicator area expands.

Cheers,
Bart

[Mark D Segal]

Hi Mark,

That visual approach would only work if the display has the same gamut as the output medium/paper&ink one uses. That is very unlikely to be the case, so a proper Out-of-Gamut (OOG) warning would be a better indicator, and would still allow to judge the effect of gamut clipping, even on lower or mismatched display gamuts.

The difficulty with most OOG indicators is that they do not show the amount of OOG-ness, just that it is OOG. In that case it can help to vary the saturation and see how fast the OOG indicator area expands.

Cheers,
Bart

Bart, it may be less unlikely than you think. Those of using wide gamut displays are seeing the image at about 98% of ARGB(98). Even our best inkjet printers and paper/ink combinations exceed that gamut "somewhat" in some areas of the spectrum, so for people using those displays (more and more common) the predictability of the saturation impact is pretty darn good. At least that's my experience, using a properly calibrated and profiled (with BasicColor) NEC PA271W display, printing from an Epson 4900 or P800 on Ilford Gold Fibre Silk most of the time. The difficulty you mention with OOG indicators is true, but spreading the area doesn't fully resolve that issue because as you spread or recede, while the OOG area may spread and recede accordingly, the depth of the "OOG-ness" is still not completely clarified. So those are the reasons why for this particular adjustment I prefer to trust my eyes.

[braga]

I tend to agree with Jeff on this point, and I print from an LR softproof routinely. The thing to watch for - on the display image with the softproof active is whether gamut clipping occurs when you increase saturation. This means whether you see image detail being obliterated by excessive colour. If that happens, unless you really want those very strong colours, you would normally dial-back saturation until the appropriate amount of image detail re-emerges. Using this kind of judgment is more important than a gamut warning.

 

thank you Mark. I felt in love with print after a presentation on my camera club (toronto camera club) last year, but is pretty hard and expensive learn about print. maybe one day you have time for make workshop for us in toronto.

[Mark D Segal]

thank you Mark. I felt in love with print after a presentation on my camera club (toronto camera club) last year, but is pretty hard and expensive learn about print. maybe one day you have time for make workshop for us in toronto.

You are welcome braga - some years ago I did conduct such a workshop in Toronto, when Michael still had his gallery on Carlaw. To do something like that again I would need a sponsor and a venue. However, a more practical idea for you, if you are a member of the website, is to go to the video tutorials and download/watch the video tutorials that Michael and Jeff did on Lightroom and From Camera to Print - those are excellent learning resources and free for members - tremendous value and education there.

[Bart_van_der_Wolf]

Bart, it may be less unlikely than you think. Those of using wide gamut displays are seeing the image at about 98% of ARGB(98). Even our best inkjet printers and paper/ink combinations exceed that gamut "somewhat" in some areas of the spectrum, so for people using those displays (more and more common) the predictability of the saturation impact is pretty darn good.

Mark, I see two issues with the suggested approach, besides the obvious requirement for a Wide-Gamut display. First, as you mentioned, the output medium can (more so as inks improve) exceed the gamut of 98% of Adobe RGB in the RGB axes. But secondly, even more likely is that the gamut will exceed that of an RGB display in the CMY axes, due to the fact that ink/paper is in a subtractive CMY (and more) colorspace.

The difficulty you mention with OOG indicators is true, but spreading the area doesn't fully resolve that issue because as you spread or recede, while the OOG area may spread and recede accordingly, the depth of the "OOG-ness" is still not completely clarified. So those are the reasons why for this particular adjustment I prefer to trust my eyes.

The 'eyes-based' advice is more likely to fail, exactly on those very saturated colors that we'd want to keep in check (Cyan-blues are a typical case). Luckily, and that's why one can get away with it, many actual scenes do not extend to (all of) the boundaries of the gamut of the paper/ink gamut, or only small parts of the image do.

That's why I use a Photoshop Difference layer approach for all those 'harder cases', by taking the absolute difference between the original image, and the converted to output profile image. That difference is a proportional signal for 'OOG-ness', and it can be used as a mask to locally reduce saturation (or twist Hue, or reduce Lightness) to better fit that of the paper/ink gamut, but only where it matters(!) while leaving the rest of the image untouched. All can be achieved in a single action, with one mouse click.

Cheers,
Bart

[Mark D Segal]

The 'eyes-based' advice is more likely to fail,

Cheers,
Bart

The point I'm trying to make is - that at least for me - it does not fail. And as my files seldom leave Lightroom from ingestion to print, using Photoshop layers, neat as the technique you describe is, just makes added work and storage space. But for those who feel they can't trust their eyes and their judgment between the softproof and the print and don't mind printing TIFF/PSD files from Photoshop, what you are suggesting makes technical sense.

[Farmer]

If you're consistently finding images with color gamuts that are causing concern, then investing in something like Color Think could be worthwhile - you could then visualise exactly how your image sits compared to a particular profile gamut.  Coupled with Bart's differential technique, you'll be pretty technically accurate in adjusting the image colour.

That said, I actually agree more with Mark's approach.  If you have a particular media on a particular printer and a consistent workflow, you tend to be able to see what's going to be an issue and what isn't and adjust it accordingly.  Ultimately, it's about whether the print looks great and as good as you want it to look.

Both approaches are valid.