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Measuring color casts in black and white prints

Measuring color casts in black and white prints

2014-11-29 by japty4644@...

Hi,


I had some questions for the individuals in this forum a month or so ago. I learned much information about B & W printing. At this point, I do not want to give up on my Canon iPF 6300 because I still think I can get the B & W output that I am looking for from it. I have what I think is a well calibrated Eizo monitor. In PS 2014 my processed B & W images look pretty neutral. When I print them they appear to have a slight color cast. So it looks like the printer is adding some color here. I do not mind printing a full sized version and then making some adjustments so that the second hard print is pretty much where I want it.


The problem is that I cannot tell with certainty what the color cast is. If I knew it was magenta or green I can easily correct that in PS. Because of metamerism it will change in different lighting conditions. I just purchased a used i1 Photo Pro 2 Spectrophotometer to see if I can spot check some areas in the print to determine which way the correct needs to go. It will give me LAB color data. If I get a negative number for the "a" channel does that mean that the spot area measured has too much green in it? How reliable is this method? Which areas should I be spot checking, shadows, highlights and mid-grays or just the grays?


I do not want to buy an Epson right now, nor do I want to get into piezographic inks etc. What I would like to do is improve my situation as it stands. I am using color profiles now. Maybe someone can tell me how to optimize these profiles for B & W. I have watched a number of X-rite videos. I saw one which mentioned Gray component replacement but did not explain very well how to go about it. Another mentioned patch weighting and using a more negative number instead of the default of 0, but I cannot seem to use that option. I am going to assume that it is only available with CMYK printing.


Any help to get some improvement here would be greatly appreciated.


Thank you,


Jim







Re: [Digital BW] Measuring color casts in black and white prints

2014-11-29 by Paul Roark

I find if very helpful to print 21-step test strips, measure them with a spectro, and then graph the results in Excel (Insert a Line Chart). With my DataColor Spyder the text output is in a format that puts the Lab L, A and B values into columns when opened with Excel. (The a1 output may need to be formatted with separate software first, but someone else is going to have to comment on that issue.) I graph the L separately from the combined Lab A and B results. It's just a matter of highlighting the columns and then going to the top of Excel and looking at the Chart options in the Insert tab.

Look at the Lab A and B valued relative to the paper white. Usually for a relatively neutral looking print the Lab A values will be very close to the paper white value. Many if not most like the Lab B values to rise a bit above the paper white, thus being a bit warmer.

I don't know of a way to get into an existing ICC and modify it. You can use Photoshop curves on an RGB version of the file to adjust the input values. There is no tutorial on this as far as I know. Frankly, I'd start over and make my own ICC with QTR's Create ICC-RGB, which can have those adjustment curves embedded into the ICC. I wrote up some notes on that at

Paul

Show quoted textHide quoted text
On Sat, Nov 29, 2014 at 4:24 AM, japty4644@... [DigitalBlackandWhiteThePrint] <DigitalBlackandWhiteThePrint@yahoogroups.com> wrote:

Hi,


I had some questions for the individuals in this forum a month or so ago. I learned much information about B & W printing. At this point, I do not want to give up on my Canon iPF 6300 because I still think I can get the B & W output that I am looking for from it. I have what I think is a well calibrated Eizo monitor. In PS 2014 my processed B & W images look pretty neutral. When I print them they appear to have a slight color cast. So it looks like the printer is adding some color here. I do not mind printing a full sized version and then making some adjustments so that the second hard print is pretty much where I want it.


The problem is that I cannot tell with certainty what the color cast is. If I knew it was magenta or green I can easily correct that in PS. Because of metamerism it will change in different lighting conditions. I just purchased a used i1 Photo Pro 2 Spectrophotometer to see if I can spot check some areas in the print to determine which way the correct needs to go. It will give me LAB color data. If I get a negative number for the "a" channel does that mean that the spot area measured has too much green in it? How reliable is this method? Which areas should I be spot checking, shadows, highlights and mid-grays or just the grays?


I do not want to buy an Epson right now, nor do I want to get into piezographic inks etc. What I would like to do is improve my situation as it stands. I am using color profiles now. Maybe someone can tell me how to optimize these profiles for B & W. I have watched a number of X-rite videos. I saw one which mentioned Gray component replacement but did not explain very well how to go about it. Another mentioned patch weighting and using a more negative number instead of the default of 0, but I cannot seem to use that option. I am going to assume that it is only available with CMYK printing.


Any help to get some improvement here would be greatly appreciated.


Thank you,


Jim








Re: Measuring color casts in black and white prints

2014-11-29 by tyler@...

You are correct that the gray component tools and a variety of other profile building options affecting ink makeup in neutrals are only available when making CMYK profiles, for a CMYK driver like a RIP. You can however improve gray neutrality in RGB profiles with i1Publish by optimizing with a large neutral and near neutral patch set. I have one that was in circulation for some time, then it disappeared, I thought it was made available on the xrite site, but I don't easily find it there.
There are these you might take a look at-
i1Profiler .cxf Optimization Files
i1Profiler .cxf Optimization Files
i1Profiler .cxf Optimization Files
View on www.russellcottrell.com
Preview by Yahoo


But I can't vouch for them from personal experience. Any of this depends on owning i1Publish of course. For those using the Datacolor software, I believe there is a similar extended patch set for more accurate neutrals.
If you have the xrite software and want the extended gray chart that used to be available, email me and I'll see what I can do. There are usually some proprietory reasons things like this suddenly disappear from the internet.
Tyler

Re: [Digital BW] Re: Measuring color casts in black and white prints

2014-11-29 by James Petrillo

Hi Paul,
Thank you for responding. I will look into QTR's Create ICC-RGB option. At this point, I would not know which way to create a desirable curve, but it is nice to know that they can be embedded into the ICC profile.
Jim 

     On Saturday, November 29, 2014 1:58 PM, "tyler@... [DigitalBlackandWhiteThePrint]" <DigitalBlackandWhiteThePrint@yahoogroups.com> wrote:
   

     You are correct that the gray component tools and a variety of other profile building options affecting ink makeup in neutrals are only available when making CMYK profiles, for a CMYK driver like a RIP. You can however improve gray neutrality in RGB profiles with i1Publish by optimizing with a large neutral and near neutral patch set. I have one that was in circulation for some time, then it disappeared, I thought it was made available on the xrite site, but I don't easily find it there. 
There are these you might take a look at-
i1Profiler .cxf Optimization Files 
|    |
|    |       i1Profiler .cxf Optimization Files  i1Profiler .cxf Optimization Files     |    |
|      View on www.russellcottrell.com      |    Preview by Yahoo    |
|    |

   
But I can't vouch for them from personal experience. Any of this depends on owning i1Publish of course. For those using the Datacolor software, I believe there is a similar extended patch set for more accurate neutrals.
If you have the xrite software and want the extended gray chart that used to be available, email me and I'll see what I can do. There are usually some proprietory reasons things like this suddenly disappear from the internet.
Tyler  #yiv7636232284 #yiv7636232284 -- #yiv7636232284ygrp-mkp {border:1px solid #d8d8d8;font-family:Arial;margin:10px 0;padding:0 10px;}#yiv7636232284 #yiv7636232284ygrp-mkp hr {border:1px solid #d8d8d8;}#yiv7636232284 #yiv7636232284ygrp-mkp #yiv7636232284hd {color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px 0;}#yiv7636232284 #yiv7636232284ygrp-mkp #yiv7636232284ads {margin-bottom:10px;}#yiv7636232284 #yiv7636232284ygrp-mkp .yiv7636232284ad {padding:0 0;}#yiv7636232284 #yiv7636232284ygrp-mkp .yiv7636232284ad p {margin:0;}#yiv7636232284 #yiv7636232284ygrp-mkp .yiv7636232284ad a {color:#0000ff;text-decoration:none;}#yiv7636232284 #yiv7636232284ygrp-sponsor #yiv7636232284ygrp-lc {font-family:Arial;}#yiv7636232284 #yiv7636232284ygrp-sponsor #yiv7636232284ygrp-lc #yiv7636232284hd {margin:10px 0px;font-weight:700;font-size:78%;line-height:122%;}#yiv7636232284 #yiv7636232284ygrp-sponsor #yiv7636232284ygrp-lc .yiv7636232284ad {margin-bottom:10px;padding:0 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Re: [Digital BW] Re: Measuring color casts in black and white prints

2014-11-29 by James Petrillo

Hi Tyler,
It would be nice to have an extended gray chart. I really would not know which of the other optimization files to try and it looks like they may only be good for smaller sample sizes. I do not know  if I want to go much smaller.
I think I will contact X-Rite on Monday and see what they have to say. It seems to me that this should not be that difficult to identify a color cast in a print and correct it, but I am having a great deal of trouble.
Thank you,
Jim 

     On Saturday, November 29, 2014 1:58 PM, "tyler@... [DigitalBlackandWhiteThePrint]" <DigitalBlackandWhiteThePrint@yahoogroups.com> wrote:
   

     You are correct that the gray component tools and a variety of other profile building options affecting ink makeup in neutrals are only available when making CMYK profiles, for a CMYK driver like a RIP. You can however improve gray neutrality in RGB profiles with i1Publish by optimizing with a large neutral and near neutral patch set. I have one that was in circulation for some time, then it disappeared, I thought it was made available on the xrite site, but I don't easily find it there. 
There are these you might take a look at-
i1Profiler .cxf Optimization Files 
|    |
|    |       i1Profiler .cxf Optimization Files  i1Profiler .cxf Optimization Files     |    |
|      View on www.russellcottrell.com      |    Preview by Yahoo    |
|    |

   
But I can't vouch for them from personal experience. Any of this depends on owning i1Publish of course. For those using the Datacolor software, I believe there is a similar extended patch set for more accurate neutrals.
If you have the xrite software and want the extended gray chart that used to be available, email me and I'll see what I can do. There are usually some proprietory reasons things like this suddenly disappear from the internet.
Tyler  #yiv7636232284 #yiv7636232284 -- #yiv7636232284ygrp-mkp {border:1px solid #d8d8d8;font-family:Arial;margin:10px 0;padding:0 10px;}#yiv7636232284 #yiv7636232284ygrp-mkp hr {border:1px solid #d8d8d8;}#yiv7636232284 #yiv7636232284ygrp-mkp #yiv7636232284hd {color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px 0;}#yiv7636232284 #yiv7636232284ygrp-mkp #yiv7636232284ads {margin-bottom:10px;}#yiv7636232284 #yiv7636232284ygrp-mkp .yiv7636232284ad {padding:0 0;}#yiv7636232284 #yiv7636232284ygrp-mkp .yiv7636232284ad p {margin:0;}#yiv7636232284 #yiv7636232284ygrp-mkp .yiv7636232284ad a {color:#0000ff;text-decoration:none;}#yiv7636232284 #yiv7636232284ygrp-sponsor #yiv7636232284ygrp-lc {font-family:Arial;}#yiv7636232284 #yiv7636232284ygrp-sponsor #yiv7636232284ygrp-lc #yiv7636232284hd {margin:10px 0px;font-weight:700;font-size:78%;line-height:122%;}#yiv7636232284 #yiv7636232284ygrp-sponsor #yiv7636232284ygrp-lc .yiv7636232284ad {margin-bottom:10px;padding:0 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Re: [Digital BW] Measuring color casts in black and white prints

2014-12-02 by japty4644@...

Hi Paul,

I have looked at the QTR RIP and actually installed it. I cannot seem to open the Create-ICC RGB portion of it. It is on my dock of my mac but have not been able to do anything with it. I am also very confused because I really have read too much from too many individuals and am trying to incorporate their workflows into this. Some say you need the Measure Tool, others say it is an older tool and will not work. Some say use Colorport 2, others say do not. I need to simplify this to it's basic steps or I will not be able to use this.

Even if I get far enough, at some point, I really do not know how to adjust the linearization in curves to get it straight and that is just the "L" channel. I thought that the "L" channel was just for luminance. If you do not straighten out the "A" and "B" channels, how to you change the color casts?

I am a complete novice here, but I would love for someone to help me figure this out. This has been a PITA for many months and I guess I am totally frustrated at this point. I would love to pay someone for their help to solve this issue. Anyone have the time and patience?

Thank you,

Jim

Re: [Digital BW] Measuring color casts in black and white prints

2014-12-02 by Paul Roark

The way I use QTR Create ICC-RGB is to simply put it on the Desktop of my Windows machine and then drag and drop the text and PS raw file with the curve on it into the Create ICC-RGB icon. An ICC and output text file pop out onto the Desktop.

I can't help you with the i1 spectro issues. I use the Spyder from ColorData.

The linearization step is just for the Lab L.

With the Create ICC-RGB approach, the PS curves are what are used to control the Lab A and B. It is a bit of an art, where familiarity with the color wheel and PS curves is necessary. With both the PS curves and QTR, if you've making the original profiles/curves, it's a bit of an iteration process -- successive refinements based on the measured results of the last effort.

For most people, it is highly recommended that you use an existing inkset that has pre-made profiles. Also, if there are no good existing profiles, a monotone inkset is way easier to get a good print out of than an inkset that has colors in it. The higher the gamut of the colors, the tougher it is to get a good B&W.

With an OEM inkset, if there are no existing good profiles and if the OEM "Advanced B&W" (or equivalent) controls are inadequate, using an automated ICC system such as the spectro manufacturers have in their software may be a better option than trying to master PS curves.

On the other hand, buying a printer that is better supported for B&W may end up being cheaper and less frustrating than trying to deal with a color inkset that does not have appropriate profiles.

If the problem relates only to your trying to use a paper that is not supported by the OEM printer, I'd also recommend trying to stay with papers that are supported with good profiles.

For Canon, BowHaus may have solutions that would work. See http://www.trueblackandwhite.com/

The difficulty of getting a good B&W from a color inkset is the main reason for the dedicated B&W inksets. And you'll notice that most of those from MIS or Jon Cone are either monotone or have only low-gamut inks. Supporting the hundreds of different papers on the market with a color inkset is impossible.

Most B&W printers do not make their own profiles; they use those that are provided by the printer or ink seller, or are otherwise available from members of forums like this. Learning how to profile is worthwhile if one is so inclined, but most should stick with existing systems and profiles, and spend their time making great photographs.

Paul




Show quoted textHide quoted text
On Tue, Dec 2, 2014 at 7:58 AM, japty4644@yahoo.com [DigitalBlackandWhiteThePrint] <DigitalBlackandWhiteThePrint@yahoogroups.com> wrote:

Hi Paul,


I have looked at the QTR RIP and actually installed it. I cannot seem to open the Create-ICC RGB portion of it. It is on my dock of my mac but have not been able to do anything with it. I am also very confused because I really have read too much from too many individuals and am trying to incorporate their workflows into this. Some say you need the Measure Tool, others say it is an older tool and will not work. Some say use Colorport 2, others say do not. I need to simplify this to it';s basic steps or I will not be able to use this.

Even if I get far enough, at some point, I really do not know how to adjust the linearization in curves to get it straight and that is just the "L" channel. I thought that the "L" channel was just for luminance. If you do not straighten out the "A" and "B" channels, how to you change the color casts?

I am a complete novice here, but I would love for someone to help me figure this out. This has been a PITA for many months and I guess I am totally frustrated at this point. I would love to pay someone for their help to solve this issue. Anyone have the time and patience?

Thank you,

Jim


Re: Measuring color casts in black and white prints

2014-12-02 by richard@...

Lots of patience, less so of time.

The QTR-Create-ICC is a script that needs to have a valid measurement file with L*ab values from a 21 or 51 step target. Take a look at my post about how to use i1 profiler to create the measurment file and use the 51-step reference file included at the link at the end of the post, along with the 51 step target (just make sure you save the measurement file with an appropriate name to a relevant and easy to remember place on your computer). The instructions are captions on the images. I show running the linearize script, but it is the same for the create icc scripts.

Once the .txt measurement file is saved, just drag the "your_measurement_file-out.txt" onto the QTR-Create-ICC icon in the dock to run the script. That will graph the L*ab measurements and then spit out the ICC profile for you to drag to your colorsync profiles folder.

Hope that helps,
Richard Boutwell

i1 Profiler and 21x4-random QTR Step Wedges
i1 Profiler and 21x4-random QTR Step Wedges
Use the current version of i1-Profiler to linearize custom Quad Tone Rip profiles
View on www.bwmastery.com
Preview by Yahoo



RE: [Digital BW] Measuring color casts in black and white prints

2014-12-02 by Elliot Puritz

<Most B&W printers do not make their own profiles; they use those that are provided by the printer or ink seller, or are otherwise available from members of forums like this.  Learning how to profile is worthwhile if one is so inclined, but most should stick with existing systems and profiles, and spend their time making great photographs.>

 

I had a discussion with a very technically minded individual yesterday in which I posed the same question Paul:  How necessary is it to make one's own profiles; can one make excellent prints using the profiles made by you, Jon, and Richard?  I believe it reasonable to conclude that we felt that using profiles made by others would, in most instances, be perfectly adequate for most of those who are printing black and white files.  

 

 

However, I also think it fair to point out that actually viewing the profiles in QTR shows that the "structure" of the profiles can differ significantly.  For example Paul's profiles for MIS inks look completely different than the profiles that Jon provides for his inks.  Certainly such differences can be a bit puzzling to those of us who are not very knowledgeable about the mechanics of the construction of QTR printing profiles. No doubt the difference in profiles partially relate to the difference in the inks.  Nevertheless, it would be interesting if a relatively simple discussion of exactly what the curves illustrate and how such curves can be related to ink limits, etc., etc. would be welcomed.  I suspect that a "simplified" deconstruction of such curves will probably be part of Richard's new EBook.

 

Elliot
Show quoted textHide quoted text
From: DigitalBlackandWhiteThePrint@yahoogroups.com [mailto:DigitalBlackandWhiteThePrint@yahoogroups.com] 
Sent: Tuesday, December 02, 2014 11:43 AM
To: DigitalB&WPrint
Subject: Re: [Digital BW] Measuring color casts in black and white prints

 

  

The way I use QTR Create ICC-RGB is to simply put it on the Desktop of my Windows machine and then drag and drop the text and PS raw file with the curve on it into the Create ICC-RGB icon.  An ICC and output text file pop out onto the Desktop.

 

I can't help you with the i1 spectro issues.  I use the Spyder from ColorData.

 

The linearization step is just for the Lab L.

 

With the Create ICC-RGB approach, the PS curves are what are used to control the Lab A and B.  It is a bit of an art, where familiarity with the color wheel and PS curves is necessary.  With both the PS curves and QTR, if you've making the original profiles/curves, it's a bit of an iteration process -- successive refinements based on the measured results of the last effort.

 

For most people, it is highly recommended that you use an existing inkset that has pre-made profiles.  Also, if there are no good existing profiles, a monotone inkset is way easier to get a good print out of than an inkset that has colors in it.  The higher the gamut of the colors, the tougher it is to get a good B&W.  

 

With an OEM inkset, if there are no existing good profiles and if the OEM "Advanced B&W" (or equivalent) controls are inadequate, using an automated ICC system such as the spectro manufacturers have in their software may be a better option than trying to master PS curves.  

 

On the other hand, buying a printer that is better supported for B&W may end up being cheaper and less frustrating than trying to deal with a color inkset that does not have appropriate profiles.

 

If the problem relates only to your trying to use a paper that is not supported by the OEM printer, I'd also recommend trying to stay with papers that are supported with good profiles.

 

For Canon, BowHaus may have solutions that would work. See http://www.trueblackandwhite.com/ 

 

The difficulty of getting a good B&W from a color inkset is the main reason for the dedicated B&W inksets.  And you'll notice that most of those from MIS or Jon Cone are either monotone or have only low-gamut inks.  Supporting the hundreds of different papers on the market with a color inkset is impossible.  

 

Most B&W printers do not make their own profiles; they use those that are provided by the printer or ink seller, or are otherwise available from members of forums like this.  Learning how to profile is worthwhile if one is so inclined, but most should stick with existing systems and profiles, and spend their time making great photographs.

 

Paul

www.PaulRoark.com 

 

 

 

 

 

On Tue, Dec 2, 2014 at 7:58 AM, japty4644@... [DigitalBlackandWhiteThePrint] <DigitalBlackandWhiteThePrint@yahoogroups.com> wrote:

  

Hi Paul,

 

I have looked at the QTR RIP and actually installed it. I cannot seem to open the Create-ICC RGB portion of it. It is on my dock of my mac but have not been able to do anything with it. I am also very confused because I really have read too much from too many individuals and am trying to incorporate their workflows into this. Some say you need the Measure Tool, others say it is an older tool and will not work. Some say use Colorport 2, others say do not. I need to simplify this to it's basic steps or I will not be able to use this.

 

Even if I get far enough, at some point, I really do not know how to adjust the linearization in curves to get it straight and that is just the "L" channel. I thought that the "L" channel was just for luminance. If you do not straighten out the "A" and "B" channels, how to you change the color casts?

 

I am a complete novice here, but I would love for someone to help me figure this out. This has been a PITA for many months and I guess I am totally frustrated at this point. I would love to pay someone for their help to solve this issue. Anyone have the time and patience?

 

Thank you,

 

Jim

Re: [Digital BW] Measuring color casts in black and white prints

2014-12-02 by Paul Roark

While most people are probably better off with pre-made profiles, the first skill that is worth the time to acquire and gives one the net positive rewards needed is probably re-linearizing an existing profile. Making that easier for those who do not have spectros is what both Roy and I have done with the scanner-based approaches. The best such approach is the QTR StepWedge tool.

Beyond making the tools and approaches available that we develop for ourselves, the incentives and time to invest in support of the open source market are rather limited.

As we generate information in our own efforts to move forward, it does often become fragmented and hard to put together. Sadly, the Yahoo forum format no longer seems to adequately address the problems of searching the database that is generated. I'd urge those who follow this forum (and the QTR forum) to save the relevant messages in a manner that facilitates good searching. Much if not most of the information people look for is out there, but finding it is difficult.

Paul




Show quoted textHide quoted text
On Tue, Dec 2, 2014 at 9:19 AM, 'Elliot Puritz' drpuritz@... [DigitalBlackandWhiteThePrint] <DigitalBlackandWhiteThePrint@yahoogroups.com> wrote:

I had a discussion with a very technically minded individual yesterday in which I posed the same question Paul: How necessary is it to make one's own profiles; can one make excellent prints using the profiles made by you, Jon, and Richard? I believe it reasonable to conclude that we felt that using profiles made by others would, in most instances, be perfectly adequate for most of those who are printing black and white files.

However, I also think it fair to point out that actually viewing the profiles in QTR shows that the "structure" of the profiles can differ significantly. For example Paul's profiles for MIS inks look completely different than the profiles that Jon provides for his inks. Certainly such differences can be a bit puzzling to those of us who are not very knowledgeable about the mechanics of the construction of QTR printing profiles. No doubt the difference in profiles partially relate to the difference in the inks. Nevertheless, it would be interesting if a relatively simple discussion of exactly what the curves illustrate and how such curves can be related to ink limits, etc., etc. would be welcomed. I suspect that a "simplified" deconstruction of such curves will probably be part of Richard's new EBook.

Elliot

From: DigitalBlackandWhiteThePrint@yahoogroups.com [mailto:DigitalBlackandWhiteThePrint@yahoogroups.com]
Sent: Tuesday, December 02, 2014 11:43 AM
To: DigitalB&WPrint
Subject: Re: [Digital BW] Measuring color casts in black and white prints

The way I use QTR Create ICC-RGB is to simply put it on the Desktop of my Windows machine and then drag and drop the text and PS raw file with the curve on it into the Create ICC-RGB icon. An ICC and output text file pop out onto the Desktop.

I can't help you with the i1 spectro issues. I use the Spyder from ColorData.

The linearization step is just for the Lab L.

With the Create ICC-RGB approach, the PS curves are what are used to control the Lab A and B. It is a bit of an art, where familiarity with the color wheel and PS curves is necessary. With both the PS curves and QTR, if you've making the original profiles/curves, it's a bit of an iteration process -- successive refinements based on the measured results of the last effort.

For most people, it is highly recommended that you use an existing inkset that has pre-made profiles. Also, if there are no good existing profiles, a monotone inkset is way easier to get a good print out of than an inkset that has colors in it. The higher the gamut of the colors, the tougher it is to get a good B&W.

With an OEM inkset, if there are no existing good profiles and if the OEM "Advanced B&W" (or equivalent) controls are inadequate, using an automated ICC system such as the spectro manufacturers have in their software may be a better option than trying to master PS curves.

On the other hand, buying a printer that is better supported for B&W may end up being cheaper and less frustrating than trying to deal with a color inkset that does not have appropriate profiles.

If the problem relates only to your trying to use a paper that is not supported by the OEM printer, I'd also recommend trying to stay with papers that are supported with good profiles.

For Canon, BowHaus may have solutions that would work. See http://www.trueblackandwhite.com/

The difficulty of getting a good B&W from a color inkset is the main reason for the dedicated B&W inksets. And you'll notice that most of those from MIS or Jon Cone are either monotone or have only low-gamut inks. Supporting the hundreds of different papers on the market with a color inkset is impossible.

Most B&W printers do not make their own profiles; they use those that are provided by the printer or ink seller, or are otherwise available from members of forums like this. Learning how to profile is worthwhile if one is so inclined, but most should stick with existing systems and profiles, and spend their time making great photographs.

Paul

On Tue, Dec 2, 2014 at 7:58 AM, japty4644@... [DigitalBlackandWhiteThePrint] <DigitalBlackandWhiteThePrint@yahoogroups.com> wrote:

Hi Paul,

I have looked at the QTR RIP and actually installed it. I cannot seem to open the Create-ICC RGB portion of it. It is on my dock of my mac but have not been able to do anything with it. I am also very confused because I really have read too much from too many individuals and am trying to incorporate their workflows into this. Some say you need the Measure Tool, others say it is an older tool and will not work. Some say use Colorport 2, others say do not. I need to simplify this to it's basic steps or I will not be able to use this.

Even if I get far enough, at some point, I really do not know how to adjust the linearization in curves to get it straight and that is just the "L" channel. I thought that the "L" channel was just for luminance. If you do not straighten out the "A" and "B" channels, how to you change the color casts?

I am a complete novice here, but I would love for someone to help me figure this out. This has been a PITA for many months and I guess I am totally frustrated at this point. I would love to pay someone for their help to solve this issue. Anyone have the time and patience?

Thank you,

Jim


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