Why the limited gamut?

[JoshLoring]

Lights in the shop are off right now - what a day. I'll give that a try tomorrow, but keep in mind that my concern here is for B&W photo prints larger than 8"x10" - prints that I will be framing & selling, so the finest resolution is required.

Don't worry about quality loss. I print 10'x4' black and white canvases for art galleries at 720. You'll 1: save ink and 2: the end client won't notice a difference in the prints. 1440 is best for 6+ color printers. You will not notice a difference on a 4 color cmyk.

 

[Colin]

I agree that 720 would be all ya need for a 4' x 10' (especially canvas), but for something like a 16" x 20" B&W photo on paper, framed, I kinda feel that people are used to and expect a similar print quality that many now get out of a 13x17 Epson photo printer. I know I cant achieve that with my SPi, but I want to do the best possible.

Cheers.

 

[randya]

Is that basically what's involved in creating custom profiles - changing the CMYK values and test-printing over & over?

There is a whole range of articles on color management here:
http://www.mutoh.com/color_management.php


On a very basic level, profile creation involves determining how much ink it takes to get a certain density at the resolution, speed and droplet capability of your printer onto a particular media.

Linearizing to those initial ink restrictions of each color.

Making a judgement call on the overall combinations of those individual colors in combinations.

Then measuring a bunch of colors to create a look up table so that the RIP can pick the closest 'color' to the one you've designed for based on the rendering intent that you've choosen.


Some RIPs have made profiling much, much easier for standard applications, but these are still powerful tools with a learning curve for special applications.

 

[Ponto]

WOW!!!....an inciteful, educational, thought provoking, puzzling, and entertaining thread all at the same time......about the wacky world of color management which seems to be an endless source of debate....and at times "analysis to paralysis".......


JP

 

[randya]

I agree that 720 would be all ya need for a 4' x 10' (especially canvas), but for something like a 16" x 20" B&W photo on paper, framed, I kinda feel that people are used to and expect a similar print quality that many now get out of a 13x17 Epson photo printer. I know I cant achieve that with my SPi, but I want to do the best possible.

Cheers.

Depending on your printer head technology and RIP.
Higher resolutions may provide you with better image quality on glossy Photo Paper. We use all small droplets in our printers at high resolution that can give a perception of more 'depth' in the image, for lack of a better term.

Typically all other media has too much texture to make a visable difference, IMHO.

 

[Jack Knight1979]

eye4clr,

Did you watch the roland webinar for creating a profile. I didn't agree with how they taught to create a profile.

You gave a great tutorial on printingdigital back in the day about how to select ink limits of each color channel using a spectrophotometer. Thank you for that by the way!

Roland said that you turn down the color channels to prevent excessive ink in each channel based on that substrate. That was all they said for setting color limits.

That makes no sense to me. If all the ink is to heavy and you turn all the channels down to 70% and your paper has a blue hue to it, you're going to have blue prints!!!!

Why wouldn't they teach people how to properly measure the color channels with the eyeone and then limit color channels based on the output of color on that substrate?

I set my total ink limits first for the substrate, and THEN print the charts based on that output. THEN select the proper channel limits based on the eyeone readings.

Why the hell would someone set all the values, pull the channel restrictions out of the air, adjust the curves and THEN set the total ink limit? The swatches for the profile would be totally off.

Oh well. I receive compliments on our color output all the time. I'll keep doing what I'm doing.

I'm curious what you have to say about the webinar, if you had a chance to watch it. I felt like it covered about 5% of the profile making process.

I suppose it's enough to get a guy in trouble. :ROFLMAO:

 

[Bly]

Onyx 10 has automated the ink restrictions step (the only difficult part of profile creation) so you print a swatch, read it, then move on to the next step.
I was dubious at first but have been getting great results.

 

[eye4clr]

Did you watch the roland webinar for creating a profile. I didn't agree with how they taught to create a profile.

Nope, missed it.

You gave a great tutorial on printingdigital back in the day about how to select ink limits of each color channel using a spectrophotometer. Thank you for that by the way!

Aw shucks, thanks. Pretty simple 'eh. A blind person should be able to make a great profile. It's not magic, just measurements. Without a spectrophotometer it's magic.

Roland said that you turn down the color channels to prevent excessive ink in each channel based on that substrate. That was all they said for setting color limits.

That makes no sense to me. If all the ink is to heavy and you turn all the channels down to 70% and your paper has a blue hue to it, you're going to have blue prints!!!!

Why wouldn't they teach people how to properly measure the color channels with the eyeone and then limit color channels based on the output of color on that substrate?

My only guess is they are ignorant of restricting based on Chroma (saturation). Like Bly says, current versions of Onyx and Caldera tend to do a pretty darn good job of restricting on their own.

I set my total ink limits first for the substrate, and THEN print the charts based on that output. THEN select the proper channel limits based on the eyeone readings.

Why the hell would someone set all the values, pull the channel restrictions out of the air, adjust the curves and THEN set the total ink limit? The swatches for the profile would be totally off.

I'm not entirely sure I follow you here. But I'll charge forward anyway. You would never linearize before restricting, just doesn't make sense. You do *limit* after linearizing, as in setting total ink limits for black. This is the single number that controls how much total combined ink is used for black output and works in conjunction with the GCR to determine CMY against K for black.

Oh well. I receive compliments on our color output all the time. I'll keep doing what I'm doing.

Then you're doing something right. It tends to either work or not work when you do it yourself.

I'm curious what you have to say about the webinar, if you had a chance to watch it. I felt like it covered about 5% of the profile making process.

I suppose it's enough to get a guy in trouble.

I don't want to sound like a snob, because I am certainly not, but I'd rather masturbate with a fork than sit through an overly generic, incomplete "guide" to color management.

A quick note back to the performance of the current RIPs. With our relatively new Caldera install I no longer fuss with restrictions. I let it do its thing and blaze forward. So far I've gotten great results. Especially using their Relative Colorimeteric intent. Onyx never had good colorimetric intent and we always had to run Perceptual for everything.

 

[signswi]

I get pretty good results with Onyx 10.1 and relative colorimetric with black point compensation turned on, but that's a somewhat new feature.

 

[eye4clr]

I get pretty good results with Onyx 10.1 and relative colorimetric with black point compensation turned on, but that's a somewhat new feature.

I jumped off the Onyx ship at 10. So your experience is more current than mine.

 

[Bly]

I run relative colorimetric and dupont watercolor input profile and black point compensation turned on and am getting better colour than I ever have previously.
No need to go in and richen blacks in the rip as we used to in 7.

Just my experience. YMMV.

 

[Custom_Grafx]

Jack I'm very interested in what you have to say here.

I watched those webinars, and one of the steps in the "printing greys" one was completely wrong... I'm 99% sure.

They said to send K100 to VW along with a gradient from 0-100K, then a square of K50. Then to set color to "density control", and to keep adjusting the CMY till you get a neutral grey.

First problem with this, is that you're only using the K channel if you turn it to density control? The other problem is, it's still very subjective... what if my interpretation of grey is more cool than my client's?

Anyway... I'm very interested to seeing a tutorial on how to set the right individual ink limits in VW, because from all the stuff I've read, and I've read a lot, there is no definitive guide on how to set these numbers.

All the steps after that, I'm pretty comfortable with.

As for results, I can't say I'm unhappy with my results, I do seem to get good PMS matches straight off... EXCEPT for when trying to print any of the PMS greys.

Purple, great, 99% match, blue, green, etc etc... all very close... I even get great and vibrant reds which I thought weren't achievable before I got into making my own profiles. But this "trying to print cool grey 4C" kinda makes me uneasy.

Where's this tutorial on individual ink limits???

eye4clr,

Did you watch the roland webinar for creating a profile. I didn't agree with how they taught to create a profile.

You gave a great tutorial on printingdigital back in the day about how to select ink limits of each color channel using a spectrophotometer. Thank you for that by the way!

Roland said that you turn down the color channels to prevent excessive ink in each channel based on that substrate. That was all they said for setting color limits.

That makes no sense to me. If all the ink is to heavy and you turn all the channels down to 70% and your paper has a blue hue to it, you're going to have blue prints!!!!

Why wouldn't they teach people how to properly measure the color channels with the eyeone and then limit color channels based on the output of color on that substrate?

I set my total ink limits first for the substrate, and THEN print the charts based on that output. THEN select the proper channel limits based on the eyeone readings.

Why the hell would someone set all the values, pull the channel restrictions out of the air, adjust the curves and THEN set the total ink limit? The swatches for the profile would be totally off.

Oh well. I receive compliments on our color output all the time. I'll keep doing what I'm doing.

I'm curious what you have to say about the webinar, if you had a chance to watch it. I felt like it covered about 5% of the profile making process.

I suppose it's enough to get a guy in trouble. :ROFLMAO:

 

[Colin]

My head is still spinning. Apparently these settings I was making in Media Explorer (see attachment) are not changing the "profile", rather just the linearization? Apparently I need certain software to create/noodle with profiles?

See how much I don't know? I want my mommy.

 

[eye4clr]

You're right that it's wrong.

Those look to me like the Ink Restrictions.

Here is the common process for building a complete media profile (one part of which is the ICC profile).

1. ink restrictions: how much ink goes down for 100% of each individual full color ink. Generally doesn't include light inks at this stage.

2. linearization: a simple process of reading evenly incremented values for each C, M, Y, and K. Includes the light inks if there are any.

3. test for and sometimes impose Ink Limits: how much combined CMY and K are allowed to create max black.

4. build ICC profile: the easiest step in the process. This is the "smart" part of the media profile that provides the mechanism to convert incoming files to accurate color for your specific printer/ink/media/rip combination.

The only step that really takes any finesse is the ink restriction. If your rip doesn't do it automatically or does a bad job, you need to measure C and M color ramps with a proper spectophotometer to find the maximum saturation of each color, that becomes the restriction value for that individual color. Y gets used to balance the C and M to improve overall grey balance performance to not make the icc work too hard to remap color values and set you up to sometimes print without the icc and still get sell-able color. This is done by eye and takes a bit of color editing skill.

I don't know of any people who do color management that "tweak" media profiles after they're made. If done properly you don't need to tweak them. That's not to say there are those to tweak the performance of the ICC. But they are few and tend to be in the crazy fine art or photography market. In other words they don't use solvent machines. Do know that tweaking the ink restrictions undermines the whole construct of the media profile. Everything is built on top of the ink restrictions. So, tweak at your own peril.

 

[Colin]

Do know that tweaking the ink restrictions undermines the whole construct of the media profile. Everything is built on top of the ink restrictions. So, tweak at your own peril.

Hmmm, but how else do I combat the considerable pink or green tones when printing a B&W photo?

 

[Colin]

Well I'm in way over my head here; I don't have the tools, software or ability to create profiles, but this is still nagging at me:

Is adjusting the CMYK values in Media Explorer (see Color 1) any different than adjusting the CMYK values under the "Color" tab in VersaWorks (Color 2), or is it basically doing the exact same thing?

 

[eye4clr]

I'd attack those tone curves to balance the grey. At first don't sweat the colors, just focus on grey. The theory is if you get the grey "balanced" the rest will mostly fall in place.

Remember that when you're judging your edits in greys to take the printed test into the lighting condition the final output will be viewed in. Yes, it matters.

 

[Colin]

I'd attack those tone curves to balance the grey. At first don't sweat the colors, just focus on grey. The theory is if you get the grey "balanced" the rest will mostly fall in place.

Yes, it is the grays (in a B&W photo print) that I'm referring to and trying to nail. But I'm afraid my question went unanswered. I'll ask it again: "Are the adjustments to the CMYK values that we can make under the Color tab in VersaWorks essentially the same as I was erroneously doing in the Media Explorer?"

I'm not worried about the grays that I apply to vector stuff, as I use the Roland color palette system for that, which works well.

Remember that when you're judging your edits in greys to take the printed test into the lighting condition the final output will be viewed in. Yes, it matters.

Yes, I know this. Thanks.

 

[eye4clr]

It appears to me to be totally different. The sliders/curves window appear to be adjustments applied to the behavior of the overall media profile. The other window where you key in values 0-100% looks like the ink restriction and should be avoided unless you're building a new media profile from scratch.

 

[Colin]

Great - thanks!