Von Kries?

[FelixPQ]

Sorry to bother you with this, I'm just curious as to why you use the:

ARGYLL_CREATE_WRONG_VON_KRIES_OUTPUT_CLASS_REL_WP=1

Graeme seems to recommend the default Bradford version.

Thanks,

edit: PS many thanks for this tool

[doug3236]

It's related to an issue of how Absolute Colorimetric is determined. ICC profile math that the ICC profiles do don't do Bradford adaptation when converting between Rel and Abs so one gets better Lab matches between a requested Lab color and what the printed color is when measured. I first noticed that on a high OBA glossy when Argyll profile Lab values didn't come as close as i1profiler profiles using Abs. Col. This option solved that.

This has little effect unless the paper has really large amounts of OBA and you are using M0 or M1 spectral data. So under normal use with M2 measurements or low OBA paper it doesn't matter whether the option is used or not.

[FelixPQ]

Thanks for your reply. Good for me, I use mostly non OBA papers. Unfortunately, I didn't use M2, so I'll do it again.

If I understand correctly, we have no control on the tint, at least with the Pro1000, right?

This profiling is base on the premise that we use inks and papers that the driver knows about, otherwise you're on your own, right? I use non OEM inks, don't get me wrong, I obtain a significant improvement with Hahnemuhle Photo Rag Baryta using the B&W mode and a profile made for it, but it seems not as much as what you get. For another paper, Arches Watercolor, it is so so, but I' try measuring with M2 filter and will see. Again thanks.

[doug3236]

You can control the Canon 1000 B&W by selecting Printer Preferences. Then checking the B&W box. After that select the manual adj box. It will open up another dialog box where you can set a slight tint. Keep in mind that the B&W profile only adjusts the L*. So if your print B&W application requests printing Lab=(80,0,0) (a light gray) it will adjust the values sent to the driver to get L*=80. The profile can, however, be used for soft proofing and it will display the tint correctly when printing with the same driver settings the profile was made with.

[aaron-746]

Hi Felix, With non-OBA papers, M2 measurements should be very similar, if not identical to M0, since there’s no OBA to be activated by the UV frequencies, thus filtering out said UV shouldn’t make any difference, whether positive or negative, because there wasn’t any UV/OBA to start with. Just a thought I’d try and help you save some time and ink… Quick question: what did you mean when you said that “This profiling is base on the premise that we use inks and papers that the driver knows about, otherwise you're on your own, right?”. What do you mean about profiling based on the premise…ink and papers the driver knows about? How would the driver have any idea what you’re actually feeding into the printer? Even if you setup a custom media, on a Pro1000, that’s only setting things like platen gap, density/amount of ink used and paper feed. Even so, regardless of what is set, one can still insert whatever media they like, thus the driver has no clue what actual paper will be in the printer, unless using the option to detect media type, in which case the printer can still only really see if you’ve inserted a gloss or matte media, or perhaps canvas. All profile creation works this way, as far as profiles are concerned, they’ve no clue as to what kind of paper and/or inks are in use. All the profile even knows about such things are just the various Lab values for paper white and various ink densities. But that shouldn’t be any different with Doug’s ABWprofiles or any other profiles, colour or b&w. What are you actually hoping to accomplish by remeasuring the targets in M2 mode? Cheers, Aaron.

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On Mon, 30 Jan 2023 at 2:13 am, FelixPQ ***@***.***> wrote: Thanks for your reply. Good for me, I use mostly non OBA papers. Unfortunately, I didn't use M2, so I'll do it again. If I understand correctly, we have no control on the tint, at least with the Pro1000, right? This profiling is base on the premise that we use inks and papers that the driver knows about, otherwise you're on your own, right? I use non OEM inks, don't get me wrong, I obtain a significant improvement with Hahnemuhle Photo Rag Baryta using the B&W mode and a profile made for it, but it seems not as much as what you get. For another paper, Arches Watercolor, it is so so, but I' try measuring with M2 filter and will see. Again thanks. — Reply to this email directly, view it on GitHub <#2 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AYHZJ2HM7ZCAZJK77IL2YC3WU2CIXANCNFSM6AAAAAAUHPFPRM> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>