Black Point compensation

[IWC Doppel]

hi,

I can't find if LR adjusts automatically for blackpoint compensation with media type choice in LR4, I have found low IRE shadow detail a little blocked out and have compensated for in part using the ABW driver adjustment shadow tonality in advanced colour print settings. Any advice regarding black point for matt papers like HFA Museum etching, Canson PhoRag and Fotospeed Nat Text would be appreciated

Mac 10.7.5
Epson 3880
LR 4.3

[digitaldog]

All color space conversions used within Adobe app's support BPC if, when accessible, you select ACE. In LR, there's no option to select a different CMM so you get ACE and thus BPC.

[IWC Doppel]

Thanks,

Sorry to say I have tried to guess and google ACE and CMM but I have no clue !

[digitaldog]

ACE=Adobe Color Engine
CMM= Color Matching Method

[BarbaraArmstrong]

I would like to add a question on this same topic.  I am learning to use my new Canon 8300, after many years of Epson printers and printing from Photoshop.  It appears that the Canon printing plug-in does not offer black point compensation, but has the advantage of "sticky" settings.  Printing from Photoshop, I can invoke black point compensation (as I have always done in the past), but the settings are not sticky -- a real drawback.  I would love to hear from those of you with significant printing experience about how much weight I should give to using or giving up the black point compensation.  Feedback on this site has been extremely helpful to me over the years and has turned me into someone who loves to print!  --Barbara

[Rob Reiter]

I believe you can only use BPC when you have Adobe CMM installed, but Adobe has never upgraded it for 16bit, or some similar restriction that makes it less than ideal for modern color management.

I would like to add a question on this same topic.  I am learning to use my new Canon 8300, after many years of Epson printers and printing from Photoshop.  It appears that the Canon printing plug-in does not offer black point compensation, but has the advantage of "sticky" settings.  Printing from Photoshop, I can invoke black point compensation (as I have always done in the past), but the settings are not sticky -- a real drawback.  I would love to hear from those of you with significant printing experience about how much weight I should give to using or giving up the black point compensation.  Feedback on this site has been extremely helpful to me over the years and has turned me into someone who loves to print!  --Barbara

[digitaldog]

BPC should always be on. IF it isn't needed, nothing happens. If it's needed, something good happens (the black compensation is applied). Now if you have a profile that doesn't need this, having it off will be OK, but having it on and sticky makes more sense.

[bjanes]

All color space conversions used within Adobe app's support BPC if, when accessible, you select ACE. In LR, there's no option to select a different CMM so you get ACE and thus BPC.

I find this a bit confusing. In Photoshop I have ACE selected and have the option of using or not using BPC. In LR there is no option to use BPC, but use of BPC is not mandatory when one is using ACE as shown by the Photoshop option. I think the option to use BPC was omitted in LR because Mr. Hamburg's intention was to keep things as simple as possible and not offer the choice of not using it, since it should almost always be enabled.

Bill

[digitaldog]

I find this a bit confusing. In Photoshop I have ACE selected and have the option of using or not using BPC.

Correct, you're not forced to do so. IOW, ACE can operate without BPC (why I can't say, I've yet to see a case where BPC either doesn't do squat or helps).

LR is a different animal. The idea was not to provide every geeky option or preference like Photoshop. You can't turn off BPC or for that matter use another CMM. Frankly I like this behavior but it makes it more difficult to write complex books or blogs if that floats your boat <g>

[JeffKohn]

I would like to add a question on this same topic.  I am learning to use my new Canon 8300, after many years of Epson printers and printing from Photoshop.  It appears that the Canon printing plug-in does not offer black point compensation, but has the advantage of "sticky" settings.  Printing from Photoshop, I can invoke black point compensation (as I have always done in the past), but the settings are not sticky -- a real drawback.  I would love to hear from those of you with significant printing experience about how much weight I should give to using or giving up the black point compensation.  Feedback on this site has been extremely helpful to me over the years and has turned me into someone who loves to print!  --Barbara

If you're running 32-bit Photoshop, you can install the Adobe CMM and use that in the iPF print plug-in, giving you the option of using black point compensation (BPC).

If you're running x64 version of Photoshop, there's not 64-bit version of the Adobe CMM to install. So you're stuck with not having BPC if you use the iPF plug-in's color management. I've found this is not an issue with perceptual rendering intent; BPC has no effect on perceptual, at least not with any of the profiles I've used (I currently do my own profiles using i1Profiler).

For images where you want to use relative-colorimetric intent, I do not recommend using the IPF plug-in's color management on x64, because BPC does matter with rel-col (especially with canvas and matte papers). Instead, do the ICC conversion within Photoshop (using BPC), and then just disable color management in the iPF plugin.

[BarbaraArmstrong]

Thanks for the replies!  I now understand that the root of my difficulty is that I am using the 64-bit version of Photoshop, and have always used relative colorimetric for my rendering intent.  I would like to keep doing that.  Jeff, I don't understand the very last part of your message -- the part about doing the ICC conversion in Photoshop, then disabling color management in the iPF plugin.  Are you talking about somehow going from the Photoshop printer dialog to the plug-in, and printing from the plug-in, rather than directly from Photoshop?  How do I do that? --Barbara

[digitaldog]

I now understand that the root of my difficulty is that I am using the 64-bit version of Photoshop, and have always used relative colorimetric for my rendering intent.

You may want to rethink a blind conversion like this and instead, soft proof and then select the RI that just looks best. That said, IF I had to blindly set a RI, I'd pick RelCol, at least based on the profiles I use most often. But sometimes, Perceptual and maybe even Saturation may look better. Keep in mind ICC profiles don't know anything about color in context! One image may appear more desirable with Perceptual, the next RelCol. Unless you look at each, you'll never know.

[JeffKohn]

Thanks for the replies!  I now understand that the root of my difficulty is that I am using the 64-bit version of Photoshop, and have always used relative colorimetric for my rendering intent.  I would like to keep doing that.  Jeff, I don't understand the very last part of your message -- the part about doing the ICC conversion in Photoshop, then disabling color management in the iPF plugin.  Are you talking about somehow going from the Photoshop printer dialog to the plug-in, and printing from the plug-in, rather than directly from Photoshop?  How do I do that? --Barbara

I'm not suggesting you use the Photoshop print dialog. I do all my printing through the iPF plug-in because I prefer the consistent interface and also want to take advantage of the 16-bit printing path. Here are the steps I would take for rel-col printing in x64 Photoshop.

1) Make sure image is saved.
2) From edit menu, choose Convert to Profile, and convert to the printer profile using rel-col and BPC.
3) Open the iPF print plug-in, and on the Main tab set the Output Profile to "None (no color correction)".
4) Print from the iPF plug-in using the other options you normally use.
5) Make sure not to save the document after again after printing, since it's currently in printer color space rather than working color space.

[JeffKohn]

You may want to rethink a blind conversion like this and instead, soft proof and then select the RI that just looks best. That said, IF I had to blindly set a RI, I'd pick RelCol, at least based on the profiles I use most often. But sometimes, Perceptual and maybe even Saturation may look better. Keep in mind ICC profiles don't know anything about color in context! One image may appear more desirable with Perceptual, the next RelCol. Unless you look at each, you'll never know.

I agree with Andrew that soft-proof is the best approach when deciding on rendering intent, as it really depends on the specific image as well as the profile. Back in the days of using i1Match/Profilemaker Pro, I almost always preferred the rel-col intent. But with i1Profiler-generated profiles, I tend to prefer perceptual intent in the majority of cases (though not always).

[BarbaraArmstrong]

"Thank you"s to both Jeff and Andy.  Jeff, your step-by-step was exactly what I needed!  And I will start to try the comparison you suggested, Andy.  I got hooked on relative colorimetric early on, and didn't think to look further. I'm sure I'm not the only one who will be helped by the advice you two have kindly offered.  Many thanks again.  --Barbara

[David Sutton]

Thanks for the replies!  I now understand that the root of my difficulty is that I am using the 64-bit version of Photoshop, and have always used relative colorimetric for my rendering intent.  I would like to keep doing that.  Jeff, I don't understand the very last part of your message -- the part about doing the ICC conversion in Photoshop, then disabling color management in the iPF plugin.  Are you talking about somehow going from the Photoshop printer dialog to the plug-in, and printing from the plug-in, rather than directly from Photoshop?  How do I do that? --Barbara

Barbara, here's another solution. Just install the 32 bit version of Photoshop and switch to that version for printing when you want BPC in the Canon print plug in. Works fine in Windows 7.

[bjanes]

I believe you can only use BPC when you have Adobe CMM installed, but Adobe has never upgraded it for 16bit, or some similar restriction that makes it less than ideal for modern color management.

Perhaps Andrew can verify this, but AFAIK the Adobe CMM does handle 16 bit and I think you may be confusing bit depth to the printer. The Mac has offered a 16 bit printer path for some time, and 16 bit printing was enabled in Windows Vista. According to this post, the 8 bit bottleneck with Epson printers is the Epson printer drivers for windows, which are only 8 bit. 16 bit editing is essential with wide gamut spaces such as ProPhotoRGB, but 8 bits for the final output is usually sufficient to prevent posterization. In my own work with the Epson 3880 and Windows 8, I have seen no posterization in clear blue skies or other problematic tones. The author of the above article reports that many observers can see no difference between printing with the two bit depths. What have Mac users on the forum noted?

Regards,

Bill

[digitaldog]

Adobe CMM doesn't care about the bit depth of the image nor the print path, but the Adobe CMM that is accessible from the Canon Plug-in isn't 64-bit capable. So we're talking about different bit depth's in different areas.

[Schewe]

Perhaps Andrew can verify this, but AFAIK the Adobe CMM does handle 16 bit and I think you may be confusing bit depth to the printer.

If you are starting with 16-bit/channel images on Windows and print through Photoshop (or LR) using ACE, the color transform is going from 16-bit working space to 16-bit printer space in 20 bit precision before dropping the final color to 8-bits/channel. In addition to the BPC, Thomas added higher precision transforms to ACE. If you are working in 16-bit and going out to a Windows printer which is 8-bit limited (and this is a chicken/egg situation) and using ACE I seriously doubt there would be much benefit to 16-bit to the print head.

One can create an image with gradations that can band when printed to an 8-bit printer on Mac that won't band when printed as 16-bit. But you need to know how to do it and photos that have grain/noise is unlikely to exhibit the same 8/16-bit banding potential...

The question relating to the Canon print plug-in using ACE is that Adobe has only released a 32-bit version of ACE and is less likely to release a 64-bit version in the near future. So, on Windows the Canon plug-in can only use ACE when run in a 32-bit app. The plug-in will have to use something else when hosted by a 64-bit app.

[IWC Doppel]

All color space conversions used within Adobe app's support BPC if, when accessible, you select ACE. In LR, there's no option to select a different CMM so you get ACE and thus BPC.

So using Camera RAW - LR4.3 - 3880 I have BPC turned on (Which is what I want) ?