Except the channels of R,G,B and Alpha, is there a RGB Channel like in Photoshop? I couldn't find it.

[YU 5]

In PS I can select a grayscale of the whole picture with "ctrl + left click" on the RGB Channel. (Not the seperate R,B,G channels, it's the whole RGB channel.) With this RGB channel I can create a mask with the render passes really quickly. Is there no such a channel to select?

[NotMyFault]

Hi,

do you mean something like this?

https://affinity.help/photo/English.lproj/pages/Layers/LayerMasks.html

 To create a luminosity mask:

1. On the Layers panel, click on the layer's thumbnail with the  and  s pressed.
2. From the Layers panel, click Mask Layer.

 

[YU 5]

Thank you~ Yes! It works!