[Erase invisible area from masking layer]

In affinity photo you can rasterize a Layer to erase the image area that lies outside the visible image. How can I delete invisible area of a masking layer in AP ipad?

[Adjust Levels exactly]

Hallo,

in affinity photo desktop you can press the alt-key to set the black point and white point exactly if you Use Level adjustment. how does this work with affinity photo ipad? Many Thanks

[Colorspace Greyscale D50]

Hallo,

 

is the colorspace Greyscale d50 a creation from affinity or is it an Official workspace?

which Gamma have the colorspace Greyscale d50.

 

Thank you and sorry für my bad english