Hello,
Attached are files from Affinity and ON1 Photo Raw (Note that PS gives same results as ON1). The first 2 images on the first row ( layer 1 intro, layer 2 intro) are layers that I will be using to blend with a brush in Luminosity mode (lum layer mask photo). After brushing the section on the right hand side of the photo with the arch you can see that the color of the light comes through in the door way and not simply the luminance i.e. brightness (see "brushed layer w color cast photo") . This is not what I expect as I only want the brightness to come through.
The next 4 images with the On1 name in the file represent the same steps taken but this time using the ON1 Photo Raw program. I have tested this in PS and it works the same as ON1 which is the correct result. The final image "On1 brushed layer w NO color cast" shows the result after I have brushed in over the arch doorway in luminosity mode. The arch way is simply lightened without a color cast.
Luminosity blend mode via a brush is a common practice for me in my architecture work and unless Affinity defines luminosity different from PS then I believe this is a bug. Please advise.
Thanks