Colour intent for printing in Affinity Photo

[Canticleer]

Hi,

 

I’m trying to incorporate Affinity Photo in my workflow lately and I’m quite happy with the results so far, except for printing.

When I print colour images I’d like to keep colour management under control and not let the printer decide on how to render colours. And while in Affinity Photo we can set rendering intent en black point compensation in soft proofing, there is no way to do the same thing in the print dialog window to match the simulation in the soft proof. Al least not on a Mac.

I know we can set rendering intent in the preference pane of Affinity Photo, but I guess this only applies to converting newly imported images which have a different colour space than the one set in Affinity Photo.

Are there any plans on changing this in future updates?

 

Thanks,

Ivan

 

[Aad Slingerland]

Rendering intent is part of the Colour Management Section (I never found it usefull to switch from the default to another, Why do you?)

[Canticleer]

It is for Windows but not for Mac. The rendering intent I choose depends on the image and the colours it contains. One image is served best with Perceptual, the other with Relative Colorimetric.

First the print dialog window on Mac for printer controlled colour management and then for ColorSync. These are the only two options.

 

 

[Aad Slingerland]

Hmm dan houd het hier voor mij op. Anyone else please!

[walt.farrell]

I'm not a Mac user, but from a bit of reading about ColorSync, there seem to be a couple of possible workarounds for the missing "rendering intent" in the Affinity Print dialog on Mac:

1. Use the ColorSync utility to create additional versions of the printer profiles. If there's a profile you use, ColorSync can (I think) generate copies of that profile with different rendering intents. You could then choose the version of the profile you want when printing from Affinity.
    
2. Save your image as a PDF or TIFF file, then open it with the ColorSync utility and change the rendering intent of the image. Save it, then print it.

Neither of those is as friendly as being able to specify the rendering intent on the Print dialog itself. But they might provide acceptable workarounds, if I've understood the ColorSync information I read. Probably approach 1 would be easier in the long term.

[R C-R]

I am extremely far from an expert on this subject, but according to Apple's ColorSync Utility, ICC profiles intended for print output apparently should have the rendering intent already built into the profile. From what very little I understand about it, this seems to be encoded in the data of the tagged intent types that convert into & out of the profile connection space (PCS) -- the header rendering intent is derived from that ... or something like that.

Hopefully, someone who actually knows how this works can make more sense out of it.

[walt.farrell]

35 minutes ago, R C-R said:

I am extremely far from an expert on this subject, but according to Apple's ColorSync Utility, ICC profiles intended for print output apparently should have the rendering intent already built into the profile

I'm not an expert either

But some of the information I found said that although the ICC profiles will have a rendering intent built into them, sometimes (depending on the image) the user may want to use a different rendering intent, which is why ColorSync lets you change the rendering intent of a profile, or make a copy with a different rendering intent.

[R C-R]

1 minute ago, walt.farrell said:

... which is why ColorSync lets you change the rendering intent of a profile, or make a copy with a different rendering intent.

That makes sense ... except that from the ColorSync Utility User Guide there is this:

Quote

To see additional details about a device’s profile, click Open. You can select an item in the new window to display or modify information, such as individual color values.

You can also change a device’s profile using the app you use with the device. For example, you can use the Displays pane of System Preferences to select a profile for your display.

If there is a simple, straightforward way to change the rendering intent by modifying values from within the utility, I am completely clueless about how to do that -- most of the values seem to be entries in a table or matrix, or a set of curves for input/output parameters, or something else I have no idea how to adjust to obtain a new valid rendering intent.

So what I am thinking from the "using the app you use with the device" verbiage in the next paragraph is Mac users need this built into the Mac Affinity apps ... somehow. 😕

[v_kyr]

9 hours ago, Canticleer said:

It is for Windows but not for Mac. The rendering intent I choose depends on the image and the colours it contains. One image is served best with Perceptual, the other with Relative Colorimetric.

First the print dialog window on Mac for printer controlled colour management and then for ColorSync.

See: Epson SureColor P700 Mac Driver Software Tour

And eventually also: P800 Manages Colors - What happen to Color Mode? Mac (it's maybe similar to your case in terms of driver versions etc.).

-- The rendering intent related for the "Printing process":

(Re-targeting, used for converting RGB to CMYK and for digital proofing)

Absolute colorimetric (ICC-absolute colorimetric): When converting a loss in a certain color space, the colors that differ from the target color space are mapped onto the cover. The colors are both color spaces are not treated. This process is particularly interesting for digital proofs in which the proof printer (usually an inkjet printer with 6 or more colors) simulates another printing process (e.g. CMYK offset printing). Absolute colorimetric reproduction ensures that the proof controls all colors exactly like the print sequences. This procedure is mainly used if the proof is given as a template in the print shop. Since the white space must not be heard, ideally I have to receive the edition paper as proof paper in order to become or. Random evidence must not work clipping. The gamut of the printing process to be simulated must surround the management of the proof printer gamut. Similar to outputting the file to printing plate using this method

Relative colorimetric (media-relative colorimetric): The conversion is carried out as with the absolute colorimetric rendering intent, but here a paper white adjustment works. All colors of the source gamut are changed so that the white points of the two media coincide. Outside the target color space Other colors are then clipped - as with the absolute colorimetric attachment - but while maintaining the relative color location distances and differences in brightness. This method is mainly used for layout prints and when converting images from a loss in one color gamut such as from RGB to CMYK. In contrast to Perceptual, the brightness differentiations are better preserved. This method is characterized by the slightest loss of quality and is the default setting in current image processing work.

 

-- The rendering intent related by "application handling":

(Reallocation, special conversion from a certain to a smaller RGB color profile)

Perceptual / Sentient: This RI transforms the image in an optically visible manner, compensating for the relative relationships between the source colors. The human eye differs on shifts between the source colors than on an equal relationship on which relationships of the source colors remain. For documents with possible color gamut, the ideal method is because the ratio of colors and that of the gamut is preserved.
When converting from a first in a certain color space, all color distances are compressed, but the saturated equations are obtained when the saturated equations are met, since the normal color perception is much more between the saturated or neutral hues than saturated colors of the same hue . The compression is also not linear. Gamut mapping is dealt with in the tasks of the ICC profile, it is also part of the motivational. This can include the fact that motifs with colourfulness are unnecessarily compressed. This RI is particularly important when converting images to sRGB for web output.

Preserving saturation: This conversion is primarily used to obtain the most saturated colors possible in representation graphics. Maximum saturation is sought, even with the acceptance of hue shifts, but the color accuracy is preserved.

[Canticleer]

Thank you all for your replies, I appreciate it very much.

I'm not a colour management expert myself but I'm not a novice neither. And I know how the different rendering methods work. My initial question concerns the fact that the rendering methods you can set in soft proof in Affinity Photo aren't present in the print dialog.

When you translate an image from screen to print, you switch from a screen profile (that you ideally created yourself with appropriate hardware) to a printer/paper profile (that was offered by the paper manufacturer or created by yourself too). In that process you re-render the colours. But since the gamut of these two profiles will never match perfectly, you possibly get (a slight) colour shift and, more importantly, this rendering will try to correct or redirect the colours that fall out of gamut of the printer/paper profile.

Basically there are two methods to control this rendering. You can let the printer driver decide how to convert the colours from your monitor profile into the printer/paper profile or you can do the colour management yourself.

I have to admit that in the first method the Epson driver does a great job and delivers pleasing colours most of the time. But while you can set a bunch of parameters, you can't expect the print to match the colours on screen perfectly.

In the second method you control the way the software renders the monitor colours to the print colours yourself, and you aim to match the print as close as possible to the image on screen.

That's where soft proofing comes in. It's no more than a tool that simulates on screen how the print will look like, given the chosen printer/paper combination and rendering intent. So in soft proof you can experiment with colour intent en black point compensation to see what gives you the best result (and do some extra editing when needed). Once you decide what combo suits your image best, you mimic this settings in the printer dialog and print.

My issue is that Affinity Photo offers the opportunity to try out different rendering intents and to switch black point compensation on or off, so you get a simulation of how the print will look under these variables, but it doesn't offer the same possibilities in the print dialog (at least not on a Mac).

Furthermore in my experience the rendering methodes aren't absolute, they are dependent on the software that you use. I mean that the Relative Colorimetric rendering of Photoshop is not exactly the same as the Relative Colorimetric rendering of for example Capture One Pro or Mac OS ColorSync. So when you rely on what you see in the soft proofing of one software title doesn't automatically translate well into the rendering set in another title.

Until now my workflow exists of raw conversion in Capture One Pro, opening the full size image (tiff or PSD) in Photoshop to resize, perform output sharpening, soft proof - set the rendering intent - (do some final editing when needed) and print. I was hoping to ditch Photoshop and use Affinity Photo instead. And while AP does a great job at resizing and sharpening, it falls short on printing. And that's a shame, because I really like the program.

[kirkt]

Try using Print-Tool:

https://www.quadtonerip.com/html/QTRprinttool.html

I use it to control printing of color targets for profiling a printer, etc., where you need explicit control of color management.  For $39, it’s worth every penny.  They offer a 30 day free trial  

kirk

 

 

 

 

 

[Canticleer]

6 minutes ago, kirkt said:

Try using Print-Tool:

https://www.quadtonerip.com/html/QTRprinttool.html

Thank you Kirk, I'll have a look at it.

[kirkt]

You’re welcome!

kirk

[R C-R]

As I understand it (which is far from perfectly), the only 'real' color information in an image file is just a "spaceless" raw set of numbers that must be mapped into an appropriate color space (RGB, CMYK, Grey, etc.) to be useable by a device like a screen or printer. Color profiles supply the mathematical transforms that determine how the mapping is done.

So if rendering intents are built into color profiles, & we want to be able to use profiles to control the output to printers, don't we need some straightforward way to create or modify them, ideally something built into apps like the Affinity ones?

[v_kyr]

Quote

With the rendering intent (rendering target or also referred to as "priority") the user of a color management system determines which conversion method is to be used. The conversion of an image from one color space to another is called gamut mapping. It should be mentioned that two color spaces are not converted directly into one another, but instead take the detour via a media-neutral connection color space (PCS = Profile Connection Space) in order to avoid additional color distortions.

Four different rendering intents (RIs) were defined by the ICC (International Color Consortium): perception-oriented (= perceptual = photographic), relative colorimetric, absolute colorimetric (or colorimetric) and saturation-preserving (= presentation). In order to understand why, despite the same RIs, different results occur when using different programs for profiling, one must know that the RIs are not standardized. They do not correspond to any specific calculation rule or formula. So are since mid-2008 predominantly mixed forms of RIs in circulation, which can best be described as intermediate stages of the individual RIs.

The ICC divides the RIs into two categories: A) re-purposing (new purpose, this includes perceptual and saturation-maintaining) and B) re-targeting (other print edition / proof, this includes the two colorimetric).

 

[R C-R]

@v_kyr, what source are you quoting? I can't find anything with similar wording by doing a web search, or any relevant hits when I search on something like "rendering intents are not standardized."

[Alfred]

20 minutes ago, R C-R said:

@v_kyr, what source are you quoting? I can't find anything with similar wording by doing a web search, or any relevant hits when I search on something like "rendering intents are not standardized."

The words in @v_kyr’s post read like German text translated into English.

[v_kyr]

From ICC articles and papers:

• ICC_white_paper_9_workflow.pdf  (Title:  "Common Color Management Workflows & Rendering Intent Usage")

An article/paper of a study from: The Journal of Technology Studies entitled:

• "Effect of pre-defined Color Rendering Intents (CRI) on the Hue attributes in a Color Managed Workflow (CMW)"

the authors tested such things.

Further a bunch of german color & prepress service companies do write/tell the same ...

Quote

No standard for rendering intents

The transformation from one color space to another is based on the well-known formulas and algorithms of color theory. They are (just like the structure of profiles) defined by the ICC.

The strategies and algorithms for replacing colors - the rendering intents - form the core of the color computer of the color management system. But they are not standardized. How a rendering intent works is left to the developers of the color calculator (e.g. Adobe or Apple). The manufacturer's color know-how is in rendering intents - comparable to the knowledge of perfect colors in analog film.

... as does a german Wikipedia entry which deals about rendering intents!

• proofing.de - rendering intent

[Lefthand]

I was hoping that with the introduction of Affinity Photo 1.9.0 the restricted colour/rendering intent and print size/layout controls on Mac would be fixed. Unfortunately it seems not meaning that I cannot yet finally leave Adobe (all be it an old CS6 version). I suppose we'll just have to keep waiting.