Profiles for B&W (Grayscale) Images - which to use?

[_Codebreaker_]

If I create a B&W image from an RGB source is there a prefered destination profile that should be used? Equally if I create a B&W image from scratch is there a prefered profile. The destination is an Epson R2400.

This question relates to RAW images which when processed in Lightroom and then opened in Photoshop are in the Prophoto colour space, regardless of whether they are RGB or B&W.

The results are very good but does it make sense to have a B&W image with a Prophoto profile?

What does the colour management process do with B&W images?

Thxs
Colin

[Lou Dina]

Colin,

LR does not dictate that the image come into Photoshop as a ProPhoto RGB file. You can choose sRGB or Adobe RGB. For B&W, there is no good reason I can see to use ProPhoto, and I use sRGB.

I currently use a Canon iPF6100 inkjet printer. While is has a 'monochrome mode', (probably similar to Epson's ABW mode), I prefer to use custom color profiles for printing B&W and toned images. At least on the Canon with custom profiles, the results are superior. When printing B&W images and my custom RGB profiles to my inkjet, I always use RGB source files. I get a more accurate tonal distribution than I do when converting to grayscale. The opposite is true when using the Canon monochrome mode....I convert to grayscale and use the monochrome mode.

Color management works the same on a B&W image (in RGB mode) as it does with any other file. It looks at the numbers and performs a source to destination conversion for all values. In the past, it wasn't accurate enough to do a good job on B&W images, but this wasn't a flaw in the ICC spec, as much as it was inaccuracy in the profiles thenselves, and the ability of the printer. Before the Canon, I used to use either QTR or IJC/OPM for all my B&W and toned prints. I find this is no longer necessary.

I'm not familiar with the 2400, so you may wish to try printing both RGB and grayscale images via ABW and ICC profiles, using a profile for you printer/paper/ink combination. I chooses sRGB since gamut is not a consideration with B&W, and I prefer the points be spaced closer together in a smaller gamut space.

Lou

[_Codebreaker_]

Lou....

Thanks for the reply.

Yes, I realise that LR can be set to 'export' images as sRGB, Adobe or Pro and I do set these accordingly. Its just that there wasn't an option for Grayscale.

I have to say I'm impressed with the Epson ABW mode but I've always wondered if I should have Colour Management in the program (LR or PS) turned on or off. Currently I leave it on. Maybe I need to plug and play with the variables a bit more just to see what happens. 🙂

Good point about the use of sRGB colour space v distance between tones.

Thxs
Colin

[Lou Dina]

Colin,

Take this with some caution, since I am not really familiar with ABW mode in Epson printers. I suspect, however, that you are actually using a profile (inside ABW mode) of sorts behind the scenes. The driver probably looks at the mode (RGB or grayscale) then uses its own profile or inking formula to lay down ink to match tones. Using the toning sliders will increase various inks for a sepia, cool, brown, or other tone. It's probably a bit like QTR under the hood, building around a neutral axis, and of course, assuming the use of the standard Epson inkset. Again, just a guess.

I find the "Monochrome Mode" in the Canon driver works best with grayscale images, and the color profiles work best with my custom ICC profiles (when printing monochrome images). I am guessing that with the Canon driver that they expect these modes are part of the normal workflow.

Lou

[Guest]

For Advanced Black and White to work as expected, and it does work extremely well, you need to send it non color managed Adobe RGB. The one thing that ABW actually is expecting, is that the file is in a Gamma 2.2 "color" space.

You can send the printer a file that is a black and white version of Adobe RGB or a Gamma 2.2 Grayscale. It doesn't matter. The file gets mapped to the three black inks and will make a very nice black and white. If you use the Tint dialog in ABW the driver will add small amount of colored ink to create the desired tint but the image will still primarily be made of the black inks.

Another minor note. The d-max of the blackest printable black is a bit lower when printing through ABW mode as compared to a full color image. No one has ever said why this is, but it is the case nevertheless. It's something you can measure with a densitometer or spectrophotometer and something you can see just observing the prints.

[_Codebreaker_]

Many thanks for the advice.

Colin

[Guest]

I can see that this thread is relevant to my question, but unfortunately the discussion is too advanced for my present level of knowledge.  Perhaps someone would kindly put it into simple terms for me!

I am wondering whether, when printing black and white images from Lightroom 2, I should:

1. Select the ICC profile for my chosen paper & printer under 'Color Management' in Lightroom's Print Module AND select 'Color' under 'Print Settings' in my printer dialogue (in which case, presumably Color Management should be set to off in the printer dialog?);

2. Select the ICC profile for my chosen paper & printer under 'Color Management' in Lightroom's Print Module AND select 'Grayscale' under 'Print Settings' in my printer dialog.  (In this case, under Color Management, which gamma setting should I set: 1.5, 1.8 or 2.2?);

3. Select 'Managed by Printer' under 'Color Management' in Lightroom's Print Module AND select 'Color' under 'Print Settings' in my printer dialog.  (In this case, what should I set under 'Color Management' in the printer dialog?);

4. Select 'Managed by Printer' under 'Color Management' in Lightroom's Print Module AND select 'Grayscale' under 'Print Settings' in my printer dialog.  (again, which gamma setting should I set?)

With color images, I have no problem: I have a color-calibrated monitor, and use the correct ICC profile for my printer and paper.  I am just unsure what is the correct thing to do with B&W images.

Many thanks for any help anyone can offer.

[Mattis A. Falch]

This mey be the wrong place to ask, but it still seems right;

I am entering a competition that requier following:

"Save the images at 300 ppi, 8bits, in grayscale (NO RGB), as jpeg files."

My problem is that I cant seem figure a way to export anything from LR4 in grayscale, LR$ forces me to choose RGB or sRGB...
What to do?

Takker (thanks in norwegian) Mattis

[NB, colourmanagement]

Hi

yes, I'd use a normal colour profile for this

If you were using a RIP to drive your inkjet printer, you might have a special CMYK profile with high 'black generation' [ http://tinyurl.com/rtlsejc] for monochrome prints - to provide a little more visual and print run stability to print [and with some ink - savings]. But I presume you're not. 

No need to use a massive colour space like Pro photo for black and white RGB images 

You'll get better looking black (in printing its called a rich black) if you print with all the printer's inks. I guess printing with just the blacks as in Epsons black and white mode might save a bit on ink but probably not a significant amount. I think what that mode's all about is trying to

1: offset poor ICC profiles (inability to print neutral grey)

and

2: reduce the way prints change under differing lighting, which can happen more with 'monochrome' prints made with colour inks included.

Again, though, most prefer the appearance of rich black. (for example, it's used in most good mono photo book printing)

When printing inkjet mono, I actually like to slightly split tone - many "old" or even just tint the black a little - traditional black and white darkroom print processes made prints with a bit of a tint. It can be very pleasing. 

I hope this helps

if so, please "like" my reply

thanks

neil barstow, colourmanagement.net

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