Canadian Tax Stamps Mr Series. Confusing Colours

I'm getting a bit confused about the Carmines, Rose Carmines and Rose Reds….can anybody help.
The first picture is 3 different colour MR2…is one of these MR2a rose carmine



The second picture is MR3 Die I…is one of these MR3b rose red

Welcome to the club! Once things get passed "red-orange," "dark green-blue," and the like, I throw my hands up.

Well, this is always speculative when looking at images like this (usual caveats apply about colour displaying differently for every scanner/monitor etc), but I'll give it a shot.
Top row - first I would call MR2a (rose carmine), others MR2.
Second row - last I would call MR3b, first MR3, unclear on the second.

For comparison -

MR2 (carmine), MR2a (rose carmine)


MR3 (carmine, more a rose carmine from the copies I've seen), MR3b (rose red)

Gmot thanks for assistance, much obliged

Rfw125