RGB profiling vs. CMYK profiling

[Andy_warp]

I stumbled across the ability to profile in RGB through Caldera.
I am trying to understand why this should be done, other than for the use of softproofing.
The main difference I see is you can control your black generation prior to printing your profiling target.

I prefer Onyx, but have been forced to use Caldera, it plays nicer with my hardware. I have noticed that my spots can be a little muddy, I like to run the GCR a little heavy, which I suspect is the culprit.

I am rarely involved in the design process as we are typically a silent partner with little access to the end user/designer. Using this workflow strictly for designers to softproof is worthless to me.

I have a solid cmyk profile. My grays are nice and neutral. Is there a benefit to this workflow that I am missing?

Thanks in advance,
Andy-warp

P.S.: it looks like Caldera charges for this option...will it help me?

 

[xxaxx]

Hey there Andy, Caldera sells it as a better profiling setup for Dye-Sub specifically. They claim that by setting up your black levels first it gives a better color gamut in the prints if I remember correctly. They gave me the whole rundown on it during the last SGIA show but I am probably not remembering the technical details properly.

 

[Andy_warp]

Hey there Andy, Caldera sells it as a better profiling setup for Dye-Sub specifically. They claim that by setting up your black levels first it gives a better color gamut in the prints if I remember correctly. They gave me the whole rundown on it during the last SGIA show but I am probably not remembering the technical details properly.

This is interesting, as I run a grand format dyesub setup.

 

[xxaxx]

Sorry for the double post, but here is the detailed write up from caldera explaining the difference.

 

[xxaxx]

This is interesting, as I run a grand format dyesub setup.

Haha yep, you just printed a nice header sign for me less than a month ago actually.

 

[Andy_warp]

Sorry for the double post, but here is the detailed write up from caldera explaining the difference.

Sweet! Thanks xxaxx!

I don't have a high dollar Babeiri just an i1. Just doing a little R&D!

A

 

[Andy_warp]

Haha yep, you just printed a nice header sign for me less than a month ago actually.

Maybe I should be more incognito!!! LOL

We aim to please!

 

[Andy_warp]

Spoke with a rep at our printer manufacturer. She sent a screenshot of an RGB profile next to the CMYK.
The gamut size was identical. The only benefit is being able to change the black temperature by adjusting color channels.
Caveat...it does not change the whole gray ramp.

Dyedub can be unpredictable since you get zero representation at print time of color. The colors bloom when it hits 400 degrees.

We use a material with an excellent white point, so when I profiled the blacks and grays are already nice and neutral.

This could help if your rich blacks are coming out warm or cool.

We hijacked the rich black straight away anyways, and use the same build for most projects.
We found one that stays gray going to 0%...in my opinion, the whole reason you profile.

 

[Correct Color]

Bottom line is really pretty simple:

The advantage to making an RGB profile is that all of the printer control (machine state) features such as single channel ink limits, ink splits, multi-channel ink limits, black generation... everything, are done internally somewhere and you have no control over them. This is identical to the process if you don't use a RIP at all with many aqueous printers that have direct drivers and don't need a RIP, and you profile them to print directly from -- say -- Photoshop. In that case, what you're always making is an RGB profile.

The disadvantage to making an RGB profile is... exactly the same thing. You can think of it as the ultimate contone.

Maybe the settings hard-wired in are exactly the machine-state settings you want for your media and your environment, or maybe they're not. Then again, maybe you're good enough at setting machine states to get every bit of capability out of your printer... or maybe you're not.

However, there's no guarantee that gamut will be larger one way than the other, or even that one way or another will produce a better or worse result. The tale is told by how well the machine state settings reflect the optimum settings for your printer, on your media, in your environment, for the effect you're trying to achieve.

(Edited to add: Well that's what I get for shooting my mouth off without doing a little research, I guess. Turns out that in Caldera, you can indeed make your own machine states, and then create the profile as an RGB profile. And that is something new.

Kind of interesting, but...

I'm not sure of a real practical value, except for the part about controlling the black prior to printing the profile patches. That could indeed have some advantages. Or not. It'd take some pretty serious testing.

One thing I'd note though is that Caldera says one of the benefits is that by making an RGB profile, designers can then use that profile as a working space. I'd say they can use it as a soft-proofing space, which indeed some CMYK+ color spaces can't do, but I'd never recommend anyone use any machine space as a working space, for a whole host of reasons.

Anyway, it is indeed something new and different from the Caldera folks.)

 

[Andy_warp]

Bottom line is really pretty simple:

The advantage to making an RGB profile is that all of the printer control (machine state) features such as single channel ink limits, ink splits, multi-channel ink limits, black generation... everything, are done internally somewhere and you have no control over them. This is identical to the process if you don't use a RIP at all with many aqueous printers that have direct drivers and don't need a RIP, and you profile them to print directly from -- say -- Photoshop. In that case, what you're always making is an RGB profile.

The disadvantage to making an RGB profile is... exactly the same thing. You can think of it as the ultimate contone.

Maybe the settings hard-wired in are exactly the machine-state settings you want for your media and your environment, or maybe they're not. Then again, maybe you're good enough at setting machine states to get every bit of capability out of your printer... or maybe you're not.

However, there's no guarantee that gamut will be larger one way than the other, or even that one way or another will produce a better or worse result. The tale is told by how well the machine state settings reflect the optimum settings for your printer, on your media, in your environment, for the effect you're trying to achieve.

(Edited to add: Well that's what I get for shooting my mouth off without doing a little research, I guess. Turns out that in Caldera, you can indeed make your own machine states, and then create the profile as an RGB profile. And that is something new.

Kind of interesting, but...

I'm not sure of a real practical value, except for the part about controlling the black prior to printing the profile patches. That could indeed have some advantages. Or not. It'd take some pretty serious testing.

One thing I'd note though is that Caldera says one of the benefits is that by making an RGB profile, designers can then use that profile as a working space. I'd say they can use it as a soft-proofing space, which indeed some CMYK+ color spaces can't do, but I'd never recommend anyone use any machine space as a working space, for a whole host of reasons.

Anyway, it is indeed something new and different from the Caldera folks.)

This people, is why Mike Adams is the man! I'm sorry I've never parted with any funds your way.

Some of the info I have seen you put up are cornerstones to my color department...which when I started, our workhorse didn't even have density calibration, ink limits or printheads aligned. I brought that machine back from the dead, and have a new baby. My ink has a generally low gamut, but makes up for it with speed. It's a trade off.

Many of the designs I get have pantones assigned...but the designers don't even have a reference book. Just picked on screen...blech.

We push for pantone where at all possible, so we can speak the same language and match in-house. The fact is I have absolutely nailed pantones before, and had them rejected by the client once they saw their palette, as a whole. I avoid soft proofing like the plague, because the majority of the people I speak to don't understand why every pantone color isn't in my print gamut. It is a losing battle. It's all about output...at it's final scale. Our proofs emulate that, and help us build trust with our customers. Looked in to G7...but meh, I'm achieving a lot with my icc workflow. Didn't look like it guaranteed better output.

I feel that I have successful color management because I can sell everything off my machine, have nice neutral grays and I can "just do what I did before"
I achieved it by paring down every variable I could in an uncontrolled environment, and having process control in the workflow from art templates to prepress to output.
Most of my signage goes in a potpourri of show hall light temperatures anyway. Is it 100% accurate? No.

But just buying a spectro ISN'T enough. Just scanning swatches ISN'T enough.

I thought it was a new feature that Caldera was serving up, and it piqued my interest.
In all honesty, I was curious to see if Correct Color would share their input!

Andy

 

[Correct Color]

Hey Andy,

First, thanks for the kind words. That's really appreciated.

Second, though, if you read down to my edit, I do have to say that it's not quite as cut and dried as I wrote here.

Making a machine state is absolutely key to making a profile that will do everything you want it to do, and the more you now about making machine states and the more any given RIP/driver combination will allow you to use that knowledge the better profiles you'll make. And it's always been true that RGB profiles have been made off of machine states pre-determined by the manufacturer...

But it's also true that just because it's always been that way doesn't mean it always has to be that way. All of the inking controls can be set by anyone -- for good or ill -- and then once you think on it a minute, it would be just as easy to print the patches as RGB data as CMYK data. The only issue would be when and how to handle entering the black generation characteristics.

Typically, of course you know, it's done in the process of creating the CMYK (or CMYK+N) ICC itself, and also of course, there's no way to do it at all in an RGB ICC profile.

So what the fine folks at Caldera have done -- that is indeed new -- is allow you to create your own inking characteristics, then describe your black generation strategy prior to printing your profile patches, and then send RGB data (patches) and make an RGB ICC profile.

And I'm a little embarrassed to say as a Caldera dealer I wasn't even aware of this till I read this thread, opened up Caldera, and had a look.

But it's there, and it's kind of interesting.

One thing of note though is that they pitch the main benefit of doing this as taking the resulting ICC's and using them as working spaces -- which I would not at all advise doing -- and their reasoning is that that beats working in RGB and then converting to some CMYK+N color space.

Which I find kind of odd, since one beef I've always had with Caldera is that they've never let you make a true CMYK+N profile. They have always contoned the N colors in the RIP...

But anyway, interesting. And it is indeed actually something new.

Oh, and you're spot on about G7.

If you've never read this, here's the story on that: Certified Correct Color Vs G7 For Large Format Printing

Again, thanks for the kind words.

And hey, if you want to send money my way, by all means, feel free.

 

[Andy_warp]

Hey Andy,

First, thanks for the kind words. That's really appreciated.

Second, though, if you read down to my edit, I do have to say that it's not quite as cut and dried as I wrote here.

Making a machine state is absolutely key to making a profile that will do everything you want it to do, and the more you now about making machine states and the more any given RIP/driver combination will allow you to use that knowledge the better profiles you'll make. And it's always been true that RGB profiles have been made off of machine states pre-determined by the manufacturer...

But it's also true that just because it's always been that way doesn't mean it always has to be that way. All of the inking controls can be set by anyone -- for good or ill -- and then once you think on it a minute, it would be just as easy to print the patches as RGB data as CMYK data. The only issue would be when and how to handle entering the black generation characteristics.

Typically, of course you know, it's done in the process of creating the CMYK (or CMYK+N) ICC itself, and also of course, there's no way to do it at all in an RGB ICC profile.

So what the fine folks at Caldera have done -- that is indeed new -- is allow you to create your own inking characteristics, then describe your black generation strategy prior to printing your profile patches, and then send RGB data (patches) and make an RGB ICC profile.

And I'm a little embarrassed to say as a Caldera dealer I wasn't even aware of this till I read this thread, opened up Caldera, and had a look.

But it's there, and it's kind of interesting.

One thing of note though is that they pitch the main benefit of doing this as taking the resulting ICC's and using them as working spaces -- which I would not at all advise doing -- and their reasoning is that that beats working in RGB and then converting to some CMYK+N color space.

Which I find kind of odd, since one beef I've always had with Caldera is that they've never let you make a true CMYK+N profile. They have always contoned the N colors in the RIP...

But anyway, interesting. And it is indeed actually something new.

Oh, and you're spot on about G7.

If you've never read this, here's the story on that: Certified Correct Color Vs G7 For Large Format Printing

Again, thanks for the kind words.

And hey, if you want to send money my way, by all means, feel free.

Actually read this article, and looked all through your site.
I equated G7 kind of like having your profile verified to be in SWOP.
It sounds impressive, but that gamut is not very large...right?

We only run one machine, so consistency across multiple machines is not really a thing for us.

The biggest takeaway I've got from the info you've shared is how important it is to see what your machine and print environment can do...and knowing it's limitations.

I may give this new method a shot, and goof around with different black generation settings...I have it coming through like a freight train right now!
It gives me fits in shadow areas...and sometimes contracts the dynamic range in darks but gives a little pop on most images.

I would never suggest someone work in a machine state working space, I also discourage working in cmyk.
Why start with 12 crayons when you can start with 64...right?

The kind words are the least I can do. It's admirable that you share this knowledge you have gained over the years. I try to pay it forward when I can...
I feel kind of like it is a responsibility, if we don't teach up and comers all of our acquired knowledge gets lost...for no reason.

it can feel like Groundhog's Day going over resolution and proper art file creation sometimes...but I wish I would have had more help all those late nights of banging my head against the keyboard!

Please keep contributing...and I will plug your services to anyone I encounter that is looking for them!

Andy