Same colors, different RGB values ?

[laurent32]

 

Is that working as intended ?

All the red areas should be same RGB values ?

Playing with profiles doesn't seem to change things.

Maybe it's a UI problem ?

[NathanC]

Hi @laurent32,

I can't replicate this so far on an sRGB document on a Macbook, sampling from the UI gave me 255 0 0 as expected. 

Could you check if this is potentially related to your Display Colour Profile on your Mac Display Preferences? If you're able to, quit the app and then change your display profile to a standard profile such as sRGB, then launch the app and create an RGB/8 sRGB 2.1 document and then check with the picker values again.

[laurent32]

Here are my system setup :

If I want to change the profil of LCD couleur, here is what is proposed :

I can't access to SRGB…

Am I doing something wrong ?

[laurent32]

LCD Couleur goes farther…

My designer prefs :

New document :

I get same results as my initial post…

 

[loukash]

I'm seeing the same issue as @laurent32 in v1, MacOS El Capitan, MacBookPro mid-2012.
A 255-0-0 object is being sampled in the UI as 253-10-1. Once that new value has been applied to the object, it remains constant though.

[NathanC]

 @laurent32 It looks like you're in the ColourSync Utility, I'm not sure if there's a way to change your currently active profile from here.

Dependant on your Mac model this should be possible from System Preferences > Display, more info: https://support.apple.com/fr-fr/guide/mac-help/mchlf3ddc60d/mac.

2 minutes ago, loukash said:

A 255-0-0 object is being sampled in the UI as 253-10-1. Once that new value has been applied to the object, it remains constant though.

Thanks, so far in V1 and V2 I've only been able to replicate this when using certain display colour profiles on a Macbook.

[laurent32]

Not all profiles show up in designer ?

[loukash]

1 minute ago, NathanC said:

I've only been able to replicate this when using certain display colour profiles on a Macbook.

The standard profile for this MBP is "Color LCD":

Switching the display profile to sRGB actually fixes the color picker issue in Affinity, but it looks horrible otherwise. So definitely not an option.

Will check with v2 on Catalina, same MBP.

[laurent32]

10 minutes ago, NathanC said:

Dependant on your Mac model this should be possible from System Preferences

Not much I can do…

[NathanC]

3 minutes ago, loukash said:

Switching the display profile to sRGB actually fixes the color picker issue in Affinity, but it looks horrible otherwise. So definitely not an option.

Will check with v2 on Catalina, same MBP.

Having Colour LCD set on the display settings on an sRGB Affinity document colour picks from the UI correctly for me on my Macbook.

 

@laurent32 as a temporary measure try changing your Preset to 'Internet & Web (SRGB)' and then try the colour picker test in the app again to see if it then matches. I don't have a Apple Pro/XDR display to hand to replicate this with but I'll feed back when possible.

[loukash]

@NathanC, how about the Affinity color preferences? This is how I've set them up in all versions:

Also, actually I'm using f.lux to adjust the display white point properly (5000K during the day), but disabling it doesn't make a difference either.

Same on Catalina, by the way: 255-0-0 picks as 253-10-0.
Digital Color Meter picks everything in Affinity as 253-9-0 sRGB, and 255-0-26 as "native values".

[NathanC]

10 minutes ago, loukash said:

@NathanC, how about the Affinity color preferences? This is how I've set them up in all versions:

All relevant options are the same as yours, only main difference is it's Monterey 12.6, I'll see if we have a Macbook on Catalina for comparison.

[loukash]

For what it's worth, it appears to be a global issue, i.e. it affects any other apps, too, not just Affinity.
Checked in Vectornator, VectorStyler, VectorQ, Inkscape, whatever design app that runs on my Catalina:
When I create a 255-0-0 object in any of these apps, the Digital Color Meter reads it as 255-0-27 (native) and 253-9-0 (sRGB) respectively.

This is puzzling.

[laurent32]

1 hour ago, NathanC said:

Internet & Web (SRGB)

No better results…

21 minutes ago, loukash said:

For what it's worth, it appears to be a global issue, i.e. it affects any other apps, too, not just Affinity.

Not sure… seems to work ok in Pixelmator Pro…

[loukash]

1 minute ago, laurent32 said:

24 minutes ago, loukash said:

For what it's worth, it appears to be a global issue, i.e. it affects any other apps, too, not just Affinity.

Not sure… seems to work ok in Pixelmator Pro…

Alright, it's not the same issue anyway.

The actual issue with Affinity is that the color picker gradually shifts any color value being picked in either color well in the UI.
That also affects CMYK documents because the color picker switches to the RGB mode when picking a color from a well.

[NotMyFault]

The Apple "Digital Color Meter" allows to probe any pixel colour and convert between Display and sRGB colour format.

I have a Display-P3 calibrated external LG display, and everything works as expected.

 max green rectangle (Document in sRGB) will show 

• 0 / 255 / 0 (sRGB)
• 117 / 251 / 76 (P3)subpixel selection.afphoto

As the display is capable to give far more saturated green in P3, and needs to mix red and blue to get the less saturated sRGB max green.

You can spot this if taking an image from the actual LED sub-pixels with a good camera and lens. A green rectangle will be created from sub-pixels having green, red and blue active. 

 

 

• 

 

 

 

[laurent32]

The fact is the color picker should reflect the values we entered and therefor show those same values where there are shown on the screen…

Even tough we understand the systems adapts them to reflect as good as possible…

Let's say we enter 255 0 0 ; color pick should show 255 0 0 where that color is even though it is in fact :

- it's 250 1 2 for screen 1

- it's 251 2 3 for screen 2

- it's 252 4 5 for printer 1

- etc…

all depending on the peripherals profiles…

Am I logic here ?

[laurent32]

Same spot (RED) :

[lepr]

7 hours ago, NathanC said:

Having Colour LCD set on the display settings on an sRGB Affinity document colour picks from the UI correctly for me on my Macbook.

The bug has been in Affinity apps for many years, and probably from the beginning. At least it has on macOS. I don't know about the apps on Windows.

You won't see the problem when the document has sRGB profile, though, which makes sense when you consider the following paragraph.

When the colour picker samples outside the document view, the sampled RGB value is mistakenly transformed from display colour space to sRGB, instead of from display colour space to document colour space, and then that resulting value is used in the document colour space.