in simple words, please: Hue - hu??

chewing thru 'RT's Color-Correction 10.4 in fifty easy steps' tut, and getting lost in the debate about SMH/LGG, I made me the following:




a screen grab from my latest project (yep, those UFOs bomb any serious landscape photography, actually a pest here in Munich…) … on the left the un-prepped 'source'.

ok, step #1:



… applied a 345° Hue shift (prepped pic is cropped, to show the difference) - obvious effect, grass greener, sky's now purple … nice.

step #2
… exported that pic (hue 345° shift), reimported to FC, applied a 15° Hue shift and …



… surprise, no, no surprise, Hue corrected (you see no difference btw the two-times Hue shipped pic and the source! Me happy…
But…

step #3



… here, I'm in Pixelmator, applying a 15° Hue shift, import that processed pic into FCPX and:


… although the shift is in opposite direction, the colors remind of the 345° version. Hm? ok, now applying a Hue-shift of 345 should nix the 'correction', shouldn't it?



…nope, not really. LOL. And for academic purposes, other direction:



… nope, no joy.

So, management summary:
a x° Hue shift in one app doesn't find its equivalent in another app.

Why all this?
My personal Goal Of The Year is to understand how to 'match' two diff. shots, that simple. For exercise I 'bent' stills in Pixelmator and try to match'em with their originals in FCPX - actually no chance :silly: Thought this 'tinted-by-hue' is an easy one - nope.

Can someone help the chicken to cross the road? In simple sentences please … … …