Can one optimize RGB profiles for B&W prints

[EricWHiss]

Hi,
I'm been following some of the posts here and on some other forums and groups.  Recently Neil posted an adjustment curve for Harman paper for B&W printing (using RGB file mode) and in another forum a user Matt S shared a profile he made for Harman that he tweaked for B&W output and called it extended gray.  

I'm not exactly a printing novice, but have never delved into building profiles for myself.  I'm just curious in general how much gain can be had by optimizing profiles for each paper/printer combo for B&W  and Color output.    I know Colorbyte does this for their Imageprint software but I don't see this elsewhere typically.  Is there enough improvement to do this or will a really good color profile work fine in most cases?

Thanks,
Eric

[Ernst Dinkla]

Hi,
I'm been following some of the posts here and on some other forums and groups.  Recently Neil posted an adjustment curve for Harman paper for B&W printing (using RGB file mode) and in another forum a user Matt S shared a profile he made for Harman that he tweaked for B&W output and called it extended gray.   

I'm not exactly a printing novice, but have never delved into building profiles for myself.  I'm just curious in general how much gain can be had by optimizing profiles for each paper/printer combo for B&W  and Color output.    I know Colorbyte does this for their Imageprint software but I don't see this elsewhere typically.  Is there enough improvement to do this or will a really good color profile work fine in most cases?

Thanks,
Eric
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Profile editors exist, so if you think you can enhance an existing ICC profile by tweaking it for B&W prints to get for example better shadow detail then there are tools to do that.

Possibly a step further is the B&W adaption of a profile made in Print Fix Pro II where extra patches are measured to get better neutrality in the recycled profile. At least that is what I understood of the process some time ago.

Then there is the profile creator of the QuadTone Rip that builds a semi-ICC profile based on B&W printed targets, the profile is only usable for B&W printing. It can be used outside a QTR workflow like Steve Kale has done with PS + the ABW mode of the Epson K3 printers.

With B&W modes in printer drivers the amount of color ink in the print is more reduced than in the color modes (less or no composite grey), the Dmax often is a bit higher too. So one should check whether using "B&W" profiles + the color mode of the driver is delivering the best Dmax + neutrality in time. The last both in printer consistency and in light resistance. That's why I tried to use QTR profiling in B&W modes of drivers or QTR itself.


Ernst Dinkla

try: Wide_Inkjet_Printers@yahoogroups.com

[Tim Gray]

While I think BW neutrality, if that's what you are after, can be improved with a tweak to the profile, the fundamental issue is with the print driver.  Ernst mentions Quadtone which is an effecitive RIP that I use with my Epson 4000.  I believe some on the newer printers come with a some kind of advanced BW mode that may deliver better results without a RIP.

[Brian Gilkes]

Profiles are not perfect. They adjust colour and/or luminosity as best they can ,  taking into account ever present differences in the way RGB screens and CMYK prints are perceived . They can be very good , but are always approximations. They may even vary in effectiveness from one observer to another. For example some women will see differences that men do not.
No matter how good the profile they are optimised for either chromaticity (perceived colour) or luminosity (perceived tonality). A good colour profile should produce reasonable monochrome prints but a greyscale profile will usually produce a better result. A RIP can print monochome with mainly or totally black inks and not attempt to mix greys from CMY, which is more problematic. This is what makes Roy Harrington's QTRIP so good, despite difficulties in softproofing the complex toning options. The Epson Advanced B&W driver allows one coloured tone and not the split options of the QTRIP. The QTRIP simulates  analogue responses like Cool Selenium which is difficult, if not impossible with AB&W.At least in the 800 series Epson printers AB&W tend to compress and even clip shadows, requiring ink limit adustments and further tweaking , such as custom curve adjustments.If your original is colour the conversion method and the skill with which it is used is critical to the appearance of the final print
There is no simple answer. You must decide on your desired output and plan a work-flow accordingly  after lots of tests.
HTH
Brian
www.pharoseditions.com.au

[madmanchan]

I print to my 3800 using separate profiles for B&W and color. This is primarily because I  print B&W via the Epson ABW driver and print color using the standard RGB color driver. For the ABW driver I make my own (custom) ABW printer profiles, using a methodology outlined here:

http://people.csail.mit.edu/ericchan/dp/Ep...0/bwcurves.html

[EricWHiss]

I print to my 3800 using separate profiles for B&W and color. This is primarily because I  print B&W via the Epson ABW driver and print color using the standard RGB color driver. For the ABW driver I make my own (custom) ABW printer profiles, using a methodology outlined here:

http://people.csail.mit.edu/ericchan/dp/Ep...0/bwcurves.html
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Eric,
Thanks for the link and info.  Very helpful.