Hi,
if using photoshop, I can duplicate a single colour channel, duplicate it and work on it (for example with a curve or with dodge and burn). Then I can change this channel into a mask in order to mask a different layer (with the hairs of a person). This mask then influences all calour channels and seperates the hais from the background.
I am not successful, if I try the same in Affinity photo by creating a spare channel or a mask layer. The created mask has still the colour information of the former selected channel. The mask is not "black and white"
So a tutorial, how hairs can be seperated by using a channel created mask could be very useful. There is no contribution in Youtube.
Best regards
Piepsi