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2011-03-06 by grimmieoldfart
Hello guys, I read somewhere and seem to think it is buried in one of Paul's documents about adjusting the Lab A and Lab B through the ink denisty settings of different inks. I can not locate it and even though I had it written down on a yellow stickie, I can find that either. Any input would be awesome. Other than staying organized a bit better... Thanks Phil
2011-03-06 by Paul
"grimmieoldfart" <grimmieoldfart@...> wrote: > I read somewhere and seem to think it is buried in one of Paul's documents about adjusting the Lab A and Lab B through the ink denisty settings of different inks. ... This may be what you're thinking of: http://www.paulroark.com/BW-Info/UT-3D_Readme.pdf Paul www.PaulRoark.com
2011-03-06 by Phillip Kimble
Paul, Thanks for the quick response, especially on a Sunday morning. I recall reading the UT-3D document which formed the basis for higher "enlightment" ( I hate that word) of the interaction betwen the different tones and denisties of carbon ink. The piece I am thinking about is actually in a footnote of a different document. The UT-3D document states the same thing though, if there is an increase of a warm denisty the netutral curve will cause an increase in Lab b* while an increase in a cool denisty will result in a decrease of Lab b* . The footnote I am referring to takes it one step further by indicating what denisty adjustments affect the Lab a* shift of a neutral curve. My objective is to reach a fairly neutral curve on BFK Rives using the K4 approach minimizing the amount of cool ink I am using. It may be a bridge too far as the paper starts off fairly warm. Then again, it could be all of those cigarettes I smoked as a teenager too... ________________________________
From: Paul <roark.paul@...>
To: DigitalBlackandWhiteThePrint@yahoogroups.com
Sent: Sun, March 6, 2011 10:06:08 AM
Subject: [Digital BW] Re: Adjusting Lab A and Lab B through ink denisty
"grimmieoldfart" <grimmieoldfart@...> wrote:
> I read somewhere and seem to think it is buried in one of Paul's documents
>about adjusting the Lab A and Lab B through the ink denisty settings of
>different inks. ...
This may be what you're thinking of:
http://www.paulroark.com/BW-Info/UT-3D_Readme.pdf
Paul
www.PaulRoark.com
[Non-text portions of this message have been removed]2011-03-07 by Paul
Phillip Kimble <grimmieoldfart@...> wrote: > > ... > The piece I am thinking about is actually in a footnote of a different document. > > > ... > > My objective is to reach a fairly neutral curve on > BFK Rives using the K4 approach minimizing the amount > of cool ink I am using. It may be a bridge too > far as the paper starts off fairly warm. If you're using what I called the K4+ approach, with LM and LC cooling the MIS carbon -- http://www.paulroark.com/BW-Info/4K+.pdf -- then you do have full Lab A and B control. More magenta in the mix gives a higher Lab A. Adding LM and LC gives a lower Lab B. (That's a bit of a simplification, but not too far off.) Paul www.PaulRoark.com
2011-03-07 by Phillip Kimble
Paul, The Eboni K4+ approach (Epson 1400) is what I am currently working with to learn how to manage the Lab A & Lab B: K = 100% M = 30% C = 9% Y = 6% (thinking I may change this to 3%) LC = 100% C (Might change this to 30% C for LC) LM = 100% M (Might change this to 30% M for LM) What I recall is one unit of LC lowers Lab B but increases Lab A while 1 unit of LM increases Lab B but lowers Lab A. Is this correct? For sanity sake, what is a "unit". It has been several months since I have had time to "play" & couldnt remember why I had magenta with a K4 inkset. Complete control of Lab A & Lab B is the goal. Though I am beginning to think it is only possible using Photoshop curves. I still have some work & lots of testing in front of me before I solve the puzzle. ________________________________
From: Paul <roark.paul@gmail.com>
To: DigitalBlackandWhiteThePrint@yahoogroups.com
Sent: Sun, March 6, 2011 7:49:58 PM
Subject: [Digital BW] Re: Adjusting Lab A and Lab B through ink denisty
Phillip Kimble <grimmieoldfart@...> wrote:
>
> ...
> The piece I am thinking about is actually in a footnote of a different
>document.
>
>
>
> ...
>
> My objective is to reach a fairly neutral curve on
> BFK Rives using the K4 approach minimizing the amount
> of cool ink I am using. It may be a bridge too
> far as the paper starts off fairly warm.
If you're using what I called the K4+ approach, with LM and LC cooling the MIS
carbon -- http://www.paulroark.com/BW-Info/4K+.pdf -- then you do have full Lab
A and B control. More magenta in the mix gives a higher Lab A. Adding LM and LC
gives a lower Lab B. (That's a bit of a simplification, but not too far off.)
Paul
www.PaulRoark.com
[Non-text portions of this message have been removed]2011-03-07 by Paul
Phillip Kimble <grimmieoldfart@...> wrote: > > > The Eboni K4+ approach (Epson 1400) is what I am > currently working with to learn > how to manage the Lab A & Lab B: > K = 100% > M = 30% > C = 9% > Y = 6% (thinking I may change this to 3%) > LC = 100% C (Might change this to 30% CÂ for LC) > LM = 100% M (Might change this to 30% M for LM) Yes,I'd make these lighter -- easier to control and less likely to show. > > What I recall is one unit of LC lowers Lab B but increases > Lab A LC will lower Lab B but also lower Lab A. Cyan is in the bottom left quadrant of the color wheel, with a negative Lab A and negative Lab B. As an example, a Tiffen test strip with a step wedge and CMY color patches has a cyan with a Lab A & B = (-41, -47) > 1 unit of LM increases Lab B but lowers Lab A. No, LM will increase Lab A. I think most of the inkjet pigment magentas have a negative Lab B, so they'd decrease it. The Tiffen test strip's magenta = (74,0.8). The last magenta I dealt with was the Claria/Noritsu. It was almost neutral in terms of its Lab B also. > > ... Complete control of Lab A & Lab B is the > goal. Though I am beginning to think it is only possible > using Photoshop curves. If you have your gray (carbon) inks in K, M, C, and Y, you'll have a lot of trouble controlling the inkset with PS curves and the Epson driver. QTR would be much easier. Profile the carbon/gray inks first. Then add the toners -- starting with the built in curves. You can control the amounts with the ink limits. Paul www.PaulRoark.com
2011-03-07 by Phillip Kimble
Paul, I warned you I was a bit confussed. I will lower the LC & LM to about a 6% mix based on your advice. It sounds likes it doesnt take much color to smooth the tone so I am guessing somewhere between 3% - 6% ink-base should work. I have a linearized carbon warm inkset using K, M,C,Y grays. This is what spured the thought and question of controlling the Lab A & B values using the LC & LM tones. So you are saying to consider the standard Lab color matrix as the road map when trying to determine what needs to be increased or decreased and how to move from point A to point B. Which is actually very smart advice- kinda like driving from NYC to LA without a map I suppose. Worse yet, driving to LA via Omaha... I spent a lot of time last night looking, comparing, & printing different comparisons of K, LM, & LC last night using QTR. I discovered how to develop a unigue LC ramp where step 21 and Step 1 are a near match. It ramps up as normal, hits the mid tones, and drops to 0 at Step 21. Nothing useful but it is a key step in understanding the QTR Curve Creation and interpreting the curves (Show Curves). Much the same learning approach usng carbon, LM, & LC and what the output is compared to the denisty & ink limits of the individual inks. I started using QTR specifically when I switched from UT14 to K4. The whole process is much easier as there are less moving parts compared to PS. Thank you for the knowledge and advice. I am certain there will be more. Phil ________________________________
From: Paul <roark.paul@...>
To: DigitalBlackandWhiteThePrint@yahoogroups.com
Sent: Sun, March 6, 2011 11:55:43 PM
Subject: [Digital BW] Re: Adjusting Lab A and Lab B through ink denisty
Phillip Kimble <grimmieoldfart@...> wrote:
>
>
> The Eboni K4+ approach (Epson 1400) is what I am
> currently working with to learn
> how to manage the Lab A & Lab B:
> K = 100%
> M = 30%
> C = 9%
> Y = 6% (thinking I may change this to 3%)
> LC = 100% C (Might change this to 30% CÂ for LC)
> LM = 100% M (Might change this to 30% M for LM)
Yes,I'd make these lighter -- easier to control and less likely to show.
>
> What I recall is one unit of LC lowers Lab B but increases
> Lab A
LC will lower Lab B but also lower Lab A. Cyan is in the bottom left quadrant of
the color wheel, with a negative Lab A and negative Lab B. As an example, a
Tiffen test strip with a step wedge and CMY color patches has a cyan with a Lab
A & B = (-41, -47)
> 1 unit of LM increases Lab B but lowers Lab A.
No, LM will increase Lab A. I think most of the inkjet pigment magentas have a
negative Lab B, so they'd decrease it. The Tiffen test strip's magenta =
(74,0.8). The last magenta I dealt with was the Claria/Noritsu. It was almost
neutral in terms of its Lab B also.
>
> ... Complete control of Lab A & Lab B is the
> goal. Though I am beginning to think it is only possible
> using Photoshop curves.
If you have your gray (carbon) inks in K, M, C, and Y, you'll have a lot of
trouble controlling the inkset with PS curves and the Epson driver. QTR would be
much easier. Profile the carbon/gray inks first. Then add the toners -- starting
with the built in curves. You can control the amounts with the ink limits.
Paul
www.PaulRoark.com
[Non-text portions of this message have been removed]2011-03-07 by Paul
Phillip Kimble <grimmieoldfart@...> wrote: > > ... I will lower the LC & LM to about a 6% mix > based on your advice. It sounds likes it doesn't take much > color to smooth the > tone so I am guessing somewhere between 3% - 6% ink-base > should work. Actually, with the MIS glossy carbons some of the "neutral" inksets are close to 30% color. > I have a linearized carbon warm inkset using K, M,C,Y grays. > This is what spured the thought and question of controlling > the Lab A & B values using the LC & LM tones. > > > So you are saying to consider the standard Lab color matrix > as the road map when trying to determine what needs to be > increased or decreased ... Yes. I think the Lab color model is the easiest to follow and use. > I started using QTR specifically when I switched from UT14 to K4. > The whole process is much easier as there are less moving parts compared to PS. What UT14 offers is a more plug and play approach for those who do not know QTR. It also has no high gamut color dots, which matters to some. While on the 1400 with LM and LC this dots are going to be rather invisible, many are bothered when someone with a magnifier can see them. Paul www.PaulRoark.com
2011-03-08 by Phillip Kimble
Paul, Under the K4+ approach, what is the best mixture of inks you have discovered. I read where the 100%-30%-9%-6% works and another document where 100%-18%-6%-2% is also good. Thanks, Phil ________________________________
From: Paul <roark.paul@...>
To: DigitalBlackandWhiteThePrint@yahoogroups.com
Sent: Mon, March 7, 2011 11:10:06 AM
Subject: [Digital BW] Re: Adjusting Lab A and Lab B through ink denisty
Phillip Kimble <grimmieoldfart@...> wrote:
>
> ... I will lower the LC & LM to about a 6% mix
> based on your advice. It sounds likes it doesn't take much
> color to smooth the
> tone so I am guessing somewhere between 3% - 6% ink-base
> should work.
Actually, with the MIS glossy carbons some of the "neutral" inksets are close to
30% color.
> I have a linearized carbon warm inkset using K, M,C,Y grays.
> This is what spured the thought and question of controlling
> the Lab A & B values using the LC & LM tones.
>
>
> So you are saying to consider the standard Lab color matrix
> as the road map when trying to determine what needs to be
> increased or decreased ...
Yes. I think the Lab color model is the easiest to follow and use.
> I started using QTR specifically when I switched from UT14 to K4.
> The whole process is much easier as there are less moving parts compared to
PS.
What UT14 offers is a more plug and play approach for those who do not know QTR.
It also has no high gamut color dots, which matters to some. While on the 1400
with LM and LC this dots are going to be rather invisible, many are bothered
when someone with a magnifier can see them.
Paul
www.PaulRoark.com
[Non-text portions of this message have been removed]2011-03-09 by Paul
Phillip Kimble <grimmieoldfart@...> wrote: > > Paul, > > Under the K4+ approach, what is the best mixture of inks > ou have discovered. I read where the 100%-30%-9%-6% works > and another document where 100%-18%-6%-2% is also good. I've started to move to the 100-18-6-2 as the standard. There are a couple of reasons for this. First, all the 1400 carts would be available from MIS pre-loaded and in the right positions. These would be the Eb6-K, M, LM, and Y positions. Then the UT14 C and LC would plug be available and plug right in. This would allow toning and glossy cool prints. Those inks are neutralized PK and LK. Second, the 2% Eb/Carb-6 is the most neutral of the dilute inks. So, with it in the mix, particularly with the right profile, one can make a relatively neutral looking print. See page 2 of http://www.paulroark.com/BW-Info/1100-Eb4.pdf for example. The Premier Art Smooth BW with a partitioned profile that uses the 2% for the highlights is a very nice print and looks cool when matted with natural white mat board. With respect to the PA Smooth BW, I picked up some of these prints from a gallery today and had them outside, where there is a lot of UV, and they really glowed. I might add that the paper backing on that paper has a Lab B of 1.3. That might bleach down a bit, but you can see from the graph that after the OBAs burn off the print will probably look a lot like its "big brother" the un-brightened Premier Art Smooth Hot Press 325, which I believe to be the progenitor of the Epson Hot Press papers -- all very fine papers that I recommend. Paul www.PaulRoark.com