Printer color management best practise...

[kovacj]

Some background info: I'm currently printing on a Canon S900 (I believe that this message applies to almost any destkop injet printer that can be color managed). I have a Nikon D100 and save images in RAW format. I use Adobe Photoshop CS and the Camera Raw plugin to convert the images.

There are a number of options for applying a color profile for printing. I typically use Ilford Gallerie Classic Pearl Paper*, and so I use the profiles that Ilford provides. I find that I get the best results using the following workflow:

1. raw image converted to ProPhoto RGB

2. image corrected, cropped, and sharpened

3. convert image to sRGB

4. use the "Printer Color Management" print space profile. Note that I have manually associated the Ilford IGCPP9 profile as the default in the Printers and Faxes-> Printer Properties-> Color Management tab

5. in the Page Setup-> Printer-> Properties (note that this same dialog is labelled "Printing Preferences" if you invoke it via the Printer and Faxes-> printer-> Properties-> Printing Preferences button), I set the recommended Media Type and Print Quality Settings (i.e. "High Gloss Photo Film" and Quality = Fine for the Classic Pearl paper).

6. in the same Printing Properties( Preferences) dialog I set the Color Management option to Manual and then set the "Enable ICM" checkbox.
7. print

The reason I do it this way, in addition to getting consistently good results (including - get this - decent Duotone (i.e. B&W) prints out of an S900) is that I believe that there are fewer color space conversions using this technique, and that I don't know/believe that the Canon printer driver can interpret from any color space other than sRGB (the Microsoft Windows color space).

So in effect, I'm making two important assumptions. The first is that the Canon printer driver only accepts/assumes sRGB images. The second is that a color profile must be used to convert the input, and if one is not specified, the default Canon profile is used.

Can anyone comment on if these assumptions are valid, or is there something that I'm missing (as is frequently the case).

Thanks in advance,
Jarek

• nice paper, in my experience, much better fade resistance than the Smooth papers - I've stopped using Ilford Smooth papers because of rapid fading.

 

[Ethan Hansen]

Some background info: I'm currently printing on a Canon S900 (I
believe that this message applies to almost any destkop injet
printer that can be color managed). I have a Nikon D100 and save
images in RAW format. I use Adobe Photoshop CS and the Camera Raw
plugin to convert the images.

There are a number of options for applying a color profile for
printing. I typically use Ilford Gallerie Classic Pearl Paper*,
and so I use the profiles that Ilford provides. I find that I get
the best results using the following workflow:

1. raw image converted to ProPhoto RGB

2. image corrected, cropped, and sharpened

3. convert image to sRGB

One comment at this point. If you are converting to sRGB, do yourself a favor and avoid the ProPhoto RGB step. ProPhoto is a huge color space, and even with only using 16-bit functions and layers, the images are fragile. Your camera can record yellows, oranges, and magentas that fall outside the limits of Adobe RGB. Your printer can output a tiny amount of color outside aRGB as well. I am reluctant to work in PP RGB unless I am printing to a device such as a LightJet or Durst on pro grade papers. These machines can make use of the extra yellow and magenta rage; your ink jet barely does at most.

Take a look at the 3-D models of printer and camera color spaces on our web site: http://www.drycreekphoto.com/tools/printer_gamuts/

Your D100 is similar to the D70, and the i9100 model for Classic Pearl is quite close to how your S900 behaves.

4. use the "Printer Color Management" print space profile. Note

[Big SNIP]

The reason I do it this way, in addition to getting consistently
good results (including - get this - decent Duotone (i.e. B&W)
prints out of an S900) is that I believe that there are fewer color
space conversions using this technique, and that I don't
know/believe that the Canon printer driver can interpret from any
color space other than sRGB (the Microsoft Windows color space).

So in effect, I'm making two important assumptions. The first is
that the Canon printer driver only accepts/assumes sRGB images.
The second is that a color profile must be used to convert the
input, and if one is not specified, the default Canon profile is
used.

You may well have better luck using Photoshop to do all the color conversions. If nothing else, you use the Adobe Color Engine (ACE) rather than Microsoft's ICM. ACE supports Black Point Compensation, which preserves shadow details to a far greater extent than can ICM. Taks a look at the plots referenced above: by using sRGB, you are losing a wide swath of colors that your printer can easily reproduce.

--
Ethan Hansen
http://www.drycreekphoto.com/

 

[kovacj]

Hi Ethan,

Thank you for the reply.

I use the PPRGB space to edit in order to preserve as much information as possible during image adjustments - I'm now wondering if I'm adjusting the image from NEF strictly for printing, if I should be converting to sRGB off the bat?

The reason for not using Photoshop CS to convert to the print profile is that I belive that the default profile will then be applied to the image data (i.e. an additional "conversion") - I'm nowhere near sure about this.

What I'm trying to find out is how a printer driver interprets the image data, and how profiles are applied to this image data. Even more basic, I'm wondering if a Windows printer driver always assume that data is in the sRGB color space? From the research I've done so far, it appears that Windows uses sRGB as the colorspace interchange. It would be nice to do all the color conversion in Photoshop and then have the driver use this data without further conversion, I'm just not convinced that this is actually happening without a conversion to sRGB behind the scenes during the interchange between Photoshop and the printer driver.

I would really like to understand what is actually happening to the image data behind the scenes between the time that I hit the Print button and the ink dropples hit the paper.

Thanks again,
Jarek

 

[JohnB23144]

kovacj, I'm with you - I also want to understand what's going on behind the scene. I just posted some questions about printing to the S9000 and using Photoshop to do the color management. I assume that the source color space doesn't matter (I use aRGB) when printing from Photoshop, and it'll do the right thing, but I am trying to verify that I know how to keep the printer driver from also applying a profile. Why is this so hard?
JohnB

 

[N8535Y]

Kovacj: I would suggest the following workflow:

1. Set your camera to Adobe Colorspace, and leave it there whether you take in Raw or jpeg you wont have to worry about it again.

2. Save your RAW images in CS in Adobe colorspace in PSD format. ( I dont know whether it will default to this or whether you have to apply it since I do not have CS, only PS 7)

3. Set CS workspace (view/color settings) to Adobe RGB 1998. Make sure that in the "color policy settings" that you have preserve embeded profiles set.

3 Do your edits to your picture, applying soft proofing using the profile that you would be using when you print for the particular paper/printer/ink combination and save as a copy or under some other name so you keep your original.

4. Open Edit/Print with Preview. Make sure "show more options" is checked and that the box is set to "Color Management", not Output, and make sure that "Document" is checked.

You should there see what profile is attached to your source file and it should be some form of Adobe.

5. In Print space, check black point compensation, and with the drop down arrow find and enter the profile for your printer/paper/ink combination.

6. Click Print and when the Printer Properties box comes up, turn off the color management in your printer if you have not already done so.

For Canon Printer, Ethan Hansen recommends as follows, borrowing from page 10 of his target printing instructions:

Optimizing Your Printer: Canon Specific Instructions
Canon Specific Instructions

Setting up Canon printers is more straightforward, but varies between Windows and Macs:

Windows: •
Main settings tab:
o Select the appropriate media type.
o Select "Custom" Print Quality.
ƒ Choose the quality setting you wish to use.
ƒ Set the halftoning to Diffusion.
o Select Manual Color Adjustment.
ƒ Set all sliders to 0.
ƒ Turn off ICM.
ƒ Set Print Type to "None".
ƒ Set Brightness to "Normal".
• Effects Tab:
o Turn all effects off.
• Profiles tab (Note: These are printer settings, not Icc profiles):

o Save your settings with a sensible name. This is what you will use when printing with the profile.

Mac: •
Print Dialog box:
o Select the media type.
o Click the Details button.
• Detailed Settings Dialog:
o Select the print quality you want.
o Select Diffusion halftoning.
o Select the Special Effects button and disable all the effects.
o Click the Color button.
ƒ Set Color Correction to None.
ƒ Set all sliders to 0.

• Go back to the main Print Dialog box and click the Apply button to save your changes. Choose a sensible

name, as this is the setting you will need to use when printing with the profile.
http://www.drycreekphoto.com ©2002-2004 Dry Creek Photo All rights reserved

• 10 -

7. PRINT.

Hope this helps.

If you need sRGB for output, after you save the original in Adobe.PSD, you can mode/convert to sRGB and save as a Jpeg. I do not recommend "save for web" to get a Jpeg output as that seems to deteriate the quality of the picture for some reason.

Bob

Some background info: I'm currently printing on a Canon S900 (I
believe that this message applies to almost any destkop injet
printer that can be color managed). I have a Nikon D100 and save
images in RAW format. I use Adobe Photoshop CS and the Camera Raw
plugin to convert the images.

There are a number of options for applying a color profile for
printing. I typically use Ilford Gallerie Classic Pearl Paper*,
and so I use the profiles that Ilford provides. I find that I get
the best results using the following workflow:

1. raw image converted to ProPhoto RGB

2. image corrected, cropped, and sharpened

3. convert image to sRGB
4. use the "Printer Color Management" print space profile. Note
that I have manually associated the Ilford IGCPP9 profile as the
default in the Printers and Faxes-> Printer Properties-> Color
Management tab
5. in the Page Setup-> Printer-> Properties (note that this same
dialog is labelled "Printing Preferences" if you invoke it via the
Printer and Faxes-> printer-> Properties-> Printing Preferences
button), I set the recommended Media Type and Print Quality
Settings (i.e. "High Gloss Photo Film" and Quality = Fine for the
Classic Pearl paper).
6. in the same Printing Properties( Preferences) dialog I set the
Color Management option to Manual and then set the "Enable ICM"
checkbox.
7. print

The reason I do it this way, in addition to getting consistently
good results (including - get this - decent Duotone (i.e. B&W)
prints out of an S900) is that I believe that there are fewer color
space conversions using this technique, and that I don't
know/believe that the Canon printer driver can interpret from any
color space other than sRGB (the Microsoft Windows color space).

So in effect, I'm making two important assumptions. The first is
that the Canon printer driver only accepts/assumes sRGB images.
The second is that a color profile must be used to convert the
input, and if one is not specified, the default Canon profile is
used.

Can anyone comment on if these assumptions are valid, or is there
something that I'm missing (as is frequently the case).

Thanks in advance,
Jarek

• nice paper, in my experience, much better fade resistance than

the Smooth papers - I've stopped using Ilford Smooth papers because
of rapid fading.

--
Bob

 

[kovacj]

Hi Bob,

I do have Adobe RGB as the default color space in the camera. I'm in the middle of "Camera RAW with Adobe Photoshop CS - Industrial-Strength Production Techniques" by Bruce Fraser. Bruce's recommendation is to use ppRGB when working with RAW images to provide the largest possible working space.

I guess the crux of my "concern" is that, I believe but am by no means certain, that there is no color space conversion in the printer driver; i.e. the printer driver interprets whatever you send it as sRGB, regardless of the embedded color space - I've only started to look into this, but from what I can tell, Microsoft Windows does not provide a color space converter and instead relies on devices standardized to sRGB. It may be that Photoshop is smart enought to do this conversion to sRGB, in addition to applying a media specific profile, before sending the image to the printer driver, but I'm not (yet) able to confirm this - in this case the default Canon profile would also be applied (me thinks), and to me this is a sub-optimal solution (i.e. apply media profile, then default printer profile).

What is driving all this, is that using the technique described in the original message, I'm able to get reasonable results with Duotone images. If I use the more convetional apply the profile in Photoshop and disable printer color management, I get a light pink cast in the image (same image .psd file, just printed two different ways).

If anyone's been down this road before, it would be great if you could share your findinds - I have a hard time believing that this is blazing a new trail..

Thanks,
Jarek

 

[kovacj]

kovacj, I'm with you - I also want to understand what's going on
behind the scene. I just posted some questions about printing to
the S9000 and using Photoshop to do the color management. I assume
that the source color space doesn't matter (I use aRGB) when
printing from Photoshop, and it'll do the right thing, but I am
trying to verify that I know how to keep the printer driver from
also applying a profile. Why is this so hard?
JohnB

Hi JohnB,

I'm not convinced that the color space doesn't matter - based on what I've read re. Windows color management ( http://www.microsoft.com/whdc/device/display/color/default.mspx is a good starting point) - I'm willing to guess that the color space does matter. This is of course based on the assumption that the Canon print driver does not perform a color space conversion - can anyone confirm whether or not the driver has the ability to conver the color space? A media profile won't resolve a discrepancy between what the printer is expecting (sRGB?) and what the color space embedded in the image (e.g. aRGB).

I have to look very hard to see differences in color photos using different printing workflows, but with Duotone images the difference is more apparent.

I'll update this post as I find more..
Cheers,
Jarek

 

[spanky181896]

Hi Jarek

A few months ago, I posted a thread on here called 'Enable ICM', I've just done a search to look for it. I don't think it answers your actual question but you'll find all sorts of colour managment stuff regards canon/windows in that thread.

http://forums.dpreview.com/forums/read.asp?forum=1003&message=9478746

From what I can gather, I use a bit of an unorthodox workflow? I too use Print Space> Profile> Printer Colour Managment.
Print type> Photo
Brightness> Normal

I also apply the yellow slider and intensity to suit the paper I am using. I get a great monitor to screen match. [Imagine a print of a statue and buildings: all the greys, beiges and tans in the pic are fine and are the correct colour tones... it is the bright primary colours that are slightly different. The prints still look fine and the colour range 'in proportion' to the original on the screen] Anyway, I'm happy!

I did try setting the Print Space> Profile> "BJ/ 2000" canon profile and using print type> none but I found my colour gamut somewhat restricted... anyway, you can read it if you have the time/energy (it's a long thread)

Amoungst the first posts is a post by me that includes 3 workflows, Ethans I think? I'd found them on another forum.

Give it a read, it may help. Good luck

 

[JohnB23144]

You might be onto something - and it'd be nice to know for sure how all this works.
JohnB

 

[Dominic.Chan]

I'm not convinced that the color space doesn't matter - based on
what I've read re. Windows color management

Depends on how you interpret "color space doesn't matter". It is true that every colour space is different from another (and sometime in a significant matter). However, with proper colour management, you will still get the "right" printout (within the printer's limitation), regardless of what the source colour space is, since colour management will do the required conversion.

( http://www.microsoft.com/whdc/device/display/color/default.mspx is
a good starting point) - I'm willing to guess that the color space
does matter. This is of course based on the assumption that the
Canon print driver does not perform a color space conversion - can
anyone confirm whether or not the driver has the ability to conver
the color space? A media profile won't resolve a discrepancy
between what the printer is expecting (sRGB?) and what the color
space embedded in the image (e.g. aRGB).

If you turn on ICM, the driver (working with the OS) will do the colour space conversion. That's the whole purpose of ICM. Not only that, based on the media selection, the driver (at least the Canon i960) will automatically select from the correct profile to do the conversion, assuming that all the profiles are associated with the printer at the OS level.

 

[jefflins]

bookmark

Some background info: I'm currently printing on a Canon S900 (I
believe that this message applies to almost any destkop injet
printer that can be color managed). I have a Nikon D100 and save
images in RAW format. I use Adobe Photoshop CS and the Camera Raw
plugin to convert the images.

There are a number of options for applying a color profile for
printing. I typically use Ilford Gallerie Classic Pearl Paper*,
and so I use the profiles that Ilford provides. I find that I get
the best results using the following workflow:

1. raw image converted to ProPhoto RGB

2. image corrected, cropped, and sharpened

3. convert image to sRGB
4. use the "Printer Color Management" print space profile. Note
that I have manually associated the Ilford IGCPP9 profile as the
default in the Printers and Faxes-> Printer Properties-> Color
Management tab
5. in the Page Setup-> Printer-> Properties (note that this same
dialog is labelled "Printing Preferences" if you invoke it via the
Printer and Faxes-> printer-> Properties-> Printing Preferences
button), I set the recommended Media Type and Print Quality
Settings (i.e. "High Gloss Photo Film" and Quality = Fine for the
Classic Pearl paper).
6. in the same Printing Properties( Preferences) dialog I set the
Color Management option to Manual and then set the "Enable ICM"
checkbox.
7. print

The reason I do it this way, in addition to getting consistently
good results (including - get this - decent Duotone (i.e. B&W)
prints out of an S900) is that I believe that there are fewer color
space conversions using this technique, and that I don't
know/believe that the Canon printer driver can interpret from any
color space other than sRGB (the Microsoft Windows color space).

So in effect, I'm making two important assumptions. The first is
that the Canon printer driver only accepts/assumes sRGB images.
The second is that a color profile must be used to convert the
input, and if one is not specified, the default Canon profile is
used.

Can anyone comment on if these assumptions are valid, or is there
something that I'm missing (as is frequently the case).

Thanks in advance,
Jarek

• nice paper, in my experience, much better fade resistance than

the Smooth papers - I've stopped using Ilford Smooth papers because
of rapid fading.

 

[kovacj]

If you turn on ICM, the driver (working with the OS) will do the
colour space conversion. That's the whole purpose of ICM. Not
only that, based on the media selection, the driver (at least the
Canon i960) will automatically select from the correct profile to
do the conversion, assuming that all the profiles are associated
with the printer at the OS level.

Hi Dominic,

Thank you for the reply. Just for the record, I'm not having trouble getting excellent quality prints out of the S900 - using the workflow I described in the initial message, even the Duotones look pretty decent (no visible green or pink cast under a variety of lighting conditons).

I'm trying to validate some assumptions to confirm that the workflow that I use is optimal. I have not been able to find any reference to what input a print driver can accept (specificially the Canon in my case) natively (i.e. without applying any "automatic" color space conversion as I'd like to be able to control the conversion myself in Photoshop). I am currently operating on the assumption that the driver will natively only support sRGB (I would like to be wrong about this). Does the printer accept other input (e.g. CMYK) natively? Has anyone come across this information?

Best regards,
Jarek

 

[kovacj]

Hi Jarek
A few months ago, I posted a thread on here called 'Enable ICM',
I've just done a search to look for it. I don't think it answers
your actual question but you'll find all sorts of colour managment
stuff regards canon/windows in that thread.

http://forums.dpreview.com/forums/read.asp?forum=1003&message=9478746

From what I can gather, I use a bit of an unorthodox workflow? I
too use Print Space> Profile> Printer Colour Managment.
Print type> Photo
Brightness> Normal
I also apply the yellow slider and intensity to suit the paper I am
using. I get a great monitor to screen match. [Imagine a print of a
statue and buildings: all the greys, beiges and tans in the pic are
fine and are the correct colour tones... it is the bright primary
colours that are slightly different. The prints still look fine and
the colour range 'in proportion' to the original on the screen]
Anyway, I'm happy!

I did try setting the Print Space> Profile> "BJ/ 2000" canon profile
and using print type> none but I found my colour gamut somewhat
restricted... anyway, you can read it if you have the time/energy
(it's a long thread)

Amoungst the first posts is a post by me that includes 3 workflows,
Ethans I think? I'd found them on another forum.

Give it a read, it may help. Good luck

Hi spanky,

I like that handle BTW

Thank you for the link to your thread - I had glanced through it previously and it is a great thread on printing workflow - it does provide much information.

I don't know that I'll be able to answer my question without contacting Canon - my goal is to get a spec. on the supported inputs and what conversions are applied (if any); I'd like to know what format/color-space the driver converts to and when profiles are applied.

I'm also starting to dig into Microsoft ICM and the print driver SDK to try and find out more, I write software for a living so that's interesting on its own for a couple of reasons. It might take me some time to uncover this information, but I will post any findings that I come across.

Thanks again,
Jarek

 

[spanky181896]

Hey jarek

Thanks mate... at last someone appreciates the irony behind the stupid name! [I hate these screen names and the chore of finding one that hasn't been taken is often 'suicide-inducing'! especially for a yahoo or hotmail account/address] Here, I chose the stupidest name I could think of!

First off, you mentioned you use High Gloss Photo Film with Classic Gloss? I use the Photo Paper Pro setting as that was recommended by Ilford on the info sheets that came in the papers box. I haven't used the ilford gallerie profiles yet, does the profile info say use HGPF?

Likewise, Print Quality> Custom> Fine #1 & Diffusion is said to give best results... I'm not sure what you use? This is FYI...

As I say, I've not used the Ilford Gallerie profiles before, does it recomend the settings you now use?

About your Q: I do understand what you are asking (I think) but I don't know enough to help. There's two ways to do 'converting' aren't there? via photoshop or using 'enable ICM' in the driver. Can you think or theorise how the driver operates in a non-colour managed workflow? Have a think on that... it may help?

Anyway, good luck in asking Canon®, in my experience any questions that mention photoshop get pointed in the direction of Adobe! I too would like to know anything you find out, thanks

my best

 

[kovacj]

I think all this is coming down to what can the printer driver accept as input and what does it do with the data (i.e. how does it work under the covers) - i.e. if ICM is not enabled, what role does the default profile play? I started another thread with this exact question - http://forums.dpreview.com/forums/read.asp?forum=1003&message=10239027 - I unfortunately haven't had time to followup on the replies (hopefully tonight after the kids are in bed..).

To answer your question re. Ilford Classic Pearl paper (the black box, not the red one), the recommended setting is HGPF - check out C1 at http://www.ilford.com/html/us_english/prod_html/galerie/pdf/IG_Canon_Lex_Dell.pdf . If you're using Ilford paper, I would highly recommend using their profiles as it does make a difference. BTW - I really like the texture of the Smooth Pearl paper (red box) but I've stopped using it as the prints fade very quickly; Classic Pearl (black box) prints seem to be holding up well*.

Cheers,
-jk

• please note that this is based on the (brutal) "print on grandma's fridge" test.

Hey jarek
Thanks mate... at last someone appreciates the irony behind the
stupid name! [I hate these screen names and the chore of finding
one that hasn't been taken is often 'suicide-inducing'! especially
for a yahoo or hotmail account/address] Here, I chose the stupidest
name I could think of!

First off, you mentioned you use High Gloss Photo Film with Classic
Gloss? I use the Photo Paper Pro setting as that was recommended by
Ilford on the info sheets that came in the papers box. I haven't
used the ilford gallerie profiles yet, does the profile info say
use HGPF?

Likewise, Print Quality> Custom> Fine #1 & Diffusion is said to give
best results... I'm not sure what you use? This is FYI...

As I say, I've not used the Ilford Gallerie profiles before, does
it recomend the settings you now use?

About your Q: I do understand what you are asking (I think) but I
don't know enough to help. There's two ways to do 'converting'
aren't there? via photoshop or using 'enable ICM' in the driver.
Can you think or theorise how the driver operates in a non-colour
managed workflow? Have a think on that... it may help?

Anyway, good luck in asking Canon®, in my experience any questions
that mention photoshop get pointed in the direction of Adobe! I too
would like to know anything you find out, thanks

my best

 

[Phil Rose]

What is driving all this, is that using the technique described in
the original message, I'm able to get reasonable results with
Duotone images. If I use the more convetional apply the profile in
Photoshop and disable printer color management, I get a light pink
cast in the image (same image .psd file, just printed two different
ways).

...is the tell-tale sign of the so-called "double profiling" error, which would occur if you have converted your image to the printer profile (Image/Mode/Convert to profile...) in Photoshop before sending to the printer(?). You haven't done that, have you?

Phil

 

[Jeff Kohn]

One comment at this point. If you are converting to sRGB, do
yourself a favor and avoid the ProPhoto RGB step. ProPhoto is a
huge color space, and even with only using 16-bit functions and
layers, the images are fragile. Your camera can record yellows,
oranges, and magentas that fall outside the limits of Adobe RGB.
Your printer can output a tiny amount of color outside aRGB as
well. I am reluctant to work in PP RGB unless I am printing to a
device such as a LightJet or Durst on pro grade papers. These
machines can make use of the extra yellow and magenta rage; your
ink jet barely does at most.

Ethan, my workflow is a little different so I'm wondering if you can offer some insight for me. I'm shooting NEF with a D70 and using Photoshop Camera RAW to do the conversion. I'm printing with an i960 using custom profiles. While I realize that ProPhoto RGB essentially contains all visible color and is overkill, I'm using it as my working space for a couple of reasons:

1) Both my camera and printer are capable of producing colors outside of Adobe RGB, and it would seem to me that to get the most out of this equipment I would want to use a working space that fully contains the gamut of both devices. ProPhoto RGB seems to be the only color space that does that (at least, out of the ones installed on my system).

2) According to Bruce Fraser's Camera RAW book, Photoshop uses ProPhoto RGB internally during the conversion, so by keeping the file in that working space I avoid a conversion.

Given those facts does ProPhoto RGB not make sense to use as a working space? Unlike the orginal poster, I do NOT convert my images to sRGB at any point. I also do all my editing in 16-bit mode (even the plug-ins I use regularly support 16-bit now). So basically my images start out in ProPhoto RGB 16-bit and stay that way through the entire workflow, until printing when QImage will use my paper-specific custom printer profile. This approach seems to be working pretty well for me, but if there are ways to improve it I'm always open to suggestion.

Of course when generating JPEG's for the web I have to convert them to sRGB 8-bit, and with some images I do see slight color shifts when doing this. But it doesn't result in noticeable changes very often and when it does it's relatively minor. To me getting the most out of my prints is far more important than web JPEG's, so I'm not too worried about this.

Thanks,

--
Jeff Kohn
Houston, TX
http://www.pbase.com/jkohn

 

[Jeff Kohn]

I guess the crux of my "concern" is that, I believe but am by no
means certain, that there is no color space conversion in the
printer driver; i.e. the printer driver interprets whatever you
send it as sRGB, regardless of the embedded color space - I've only
started to look into this, but from what I can tell, Microsoft
Windows does not provide a color space converter and instead relies
on devices standardized to sRGB. It may be that Photoshop is smart
enought to do this conversion to sRGB, in addition to applying a
media specific profile, before sending the image to the printer
driver, but I'm not (yet) able to confirm this - in this case the
default Canon profile would also be applied (me thinks), and to me
this is a sub-optimal solution (i.e. apply media profile, then
default printer profile).

I don't think you're correct here for a couple of reasons. First, if printers only supported sRGB I don't see how there would be much point in using ICC profiles, everything would just be sRGB. Second, I've used an Eye One Photo to create my printer profiles, and resulting profiles have colors in them that exceed not only sRGB but even Adobe RGB. If the printer was only capable of working in sRGB I don't see how this would be possible. Bottom line is, I think you are limiting yourself by converting your images to sRGB.

What is driving all this, is that using the technique described in
the original message, I'm able to get reasonable results with
Duotone images. If I use the more convetional apply the profile in
Photoshop and disable printer color management, I get a light pink
cast in the image (same image .psd file, just printed two different
ways).

Are you sure you want to "Apply" the profile rather than "Convert" to it? Better yet, skip this step altogether. If printing in Photoshop I would think you would want to stay in your working color space and then in the "Print with Preview" dialog, select your printer profile and make sure that the print driver has ICM disabled. That way Photoshop should handle all color management, converting from your working space to your printer profile as part of the print process.

I'll admit I'm not an expert in Color Management, but from all I've read it seems to me for optimal results you want to avoid sRGB. I keep my images in ProPhoto RGB all the way up until printing, at which time QImage will use the appropriate printer profile. I get very accurate results with this approach, including good B&W prints.

--
Jeff Kohn
Houston, TX
http://www.pbase.com/jkohn

 

[Ethan Hansen]

kovacj wrote:
[SNIP]

I'm trying to validate some assumptions to confirm that the
workflow that I use is optimal. I have not been able to find any
reference to what input a print driver can accept (specificially
the Canon in my case) natively (i.e. without applying any
"automatic" color space conversion as I'd like to be able to
control the conversion myself in Photoshop). I am currently
operating on the assumption that the driver will natively only
support sRGB (I would like to be wrong about this). Does the
printer accept other input (e.g. CMYK) natively? Has anyone come
across this information?

The printer driver only supports RGB. If you send it CMYK data, the driver first converts to RGB using a truly awful algorithm and the converts the resulting mess back into CcMmYK. If you set the Print Type to "NONE" as recommended above, the driver does not perform any additional RGB color conversions. The output exceeds even the bounds of Adobe RGB in some colors rather than being clipped to smaller than sRGB. If your printer driver does not list the "None" setting, you need to upgrade the driver - older drivers lacked the necessary setting. Use a profile built for this setting and you can control all the color parameters in Photoshop. You can view 3-D models of the actual output range of several Canon models on our web site at:
http://www.drycreekphoto.com/tools/printer_gamuts/

--
Ethan Hansen
http://www.drycreekphoto.com/

 

[Pat]

If I'm interpreting your inquiry right, it is whether or not your printer can print in a gamut wider than sRGB. Your assumption is that it cannot, and that's why you've been converting to sRGB before printing.

But I recently read this thread and this excellent pdf by Canon that makes it clear their printers (and I suspect most high quality ink jet printers today) can render color gamuts wider than sRGB.

http://forums.dpreview.com/forums/read.asp?forum=1006&message=9561009

http://www.qualiteitems.com/canon.pdf

So essentially, you may have been limiting the printed output of your images by converting to sRGB before sending to your printer.

Like many others in this thread, I convert my raws to ProPhoto RGB and KEEP it in that color space through printing. I'll only convert to sRGB if I need to email jpegs or upload to the web.

However, my camera only offers sRGB for jpegs, so when I shoot in this format, I don't bother converting to a wider gamut when editing. That's just a personal preference made for ease and convenience.

--
Pat