Measurement patch printing

[Rawcoll]

I need to print some untagged colour and grey patches for creating a printer profile. I realise that this might be a dumb question, but can someone confirm that in order to do this I need to 'disable' colour management in the colour management dialogue please? Obviously the printer driver also needs to be set so as not to manage colour.

I query this because I've not managed to find any definitive statement to this effect either in the manual or in the forum, and I am only too well aware that unexpected things can happen behind the scenes that can return to haunt. I read the other day that Lightroom 3 can not be used to print out test targets even though it can apparently be set to leave colour management to the printer driver. The reason given is that an image without an embedded profile is automatically assigned the sRGB space. My understanding is not sufficiently deep as to be able to spot these sneaky issues!

Thanks.
Ian

[jsachs]

You don't need to disable color management, just set Custom Profile to None and set the printer driver to make no color adjustments.

[Rawcoll]

Thank you, Jonathan

[Dieter Mayr]

Jonathan,

doesn't the Working Colorspace have a influence, too, and if one converts to it or no when importing the pattern-image?

[Rawcoll]

I was wondering about that. If I have set an assumed profile as, say, sRGB, then that will be applied. Will that be a problem? It presumably was so in the Lightroom case I cited. Even if the assumed profile is set to 'none' in the Colour Management dialogue, it looks as though the image is tagged with the working colour space.

Ian

[jsachs]

Yes, when you open the file you should not convert to the current working color space. If your working color space is sRGB, it doesn't matter if you convert or not.

[Rawcoll]

Sorry Jonathan, but I think I am even more confused. As I understand it the colour patch files have no assigned colour space and should be printed "as is" without any intervening colour management. Do I take you to mean that if an untagged image is assigned, in the absence of a colour space, to for example the sRGB colour space, and that it is opened in the same working space, then the data remains unchanged? In which case printing with no profile will be the same as printing the original unassigned file without colour management?

Is disabling colour management also a valid approach?

Thanks
Ian

[jsachs]

Untagged is identical to tagging with sRGB. Every image must be in some color space or the RGB values would have no meaning at all - untagged images are assumed to be sRGB.

If don't convert the data on opening, print with Custom Profile = None, and set the driver to make no color adjustment, image data should pass through the system unmodified.

Yes, you can also disable color management.