Strange Lab color - suppose a bug in color rendering

[smg]

In the attached file I have draw a two gradient in Lab, I am preparing color course slide, so if theory is correct I will got two different colours.

Some one know why having two different Lab value they on screen appear as the same color?

Thank you

strange color.afdesign

[Pauls]

this is what I get
 

[Pauls]

you'll see a bigger difference if you lower the L value to  75

[smg]

7 minutes ago, Pauls said:

you'll see a bigger difference if you lower the L value to  75

Oh... yes. But what I was expected are different colors see attached. The color of the Lab axes. Eventually color corrected by the ICC monitor profile, but I was not expected such difference. 😃

strange color expected as in theory.afdesign

[Pauls]

the 100 L value will be shifting some of those colours - not sure where your source is from Photoshop gives similar results for me

[NotMyFault]

If you don’t trust Affinity you could use free online tools to convert from LAB to RGB.

Both LAB colors differ only slightly : 0 / 255 / 250 vs 0 / 255 / 255

Looks perfectly ok in Affinity.

[Max P]

Yes 

yes you are right,  it's a bug some day ago, in Affinity  Photo, I saw the same incoherence, very surprised.

From memory it seems to me that it was correct, some time ago

[Max P]

I just tried with Krita, l*a*b* (32 bit) L100 seems to be a special case where the terminals a* and b* on the left side have the same colour.

 

I  just learned something, this day
Pauls NotMyFault you were right,   sorry for my previous post

Merry Christmas to you