Selection Process Question

[Sandy47]

I have a photo that's uniformly dark on the right side. In PS I'd create a B&W alpha channel as a gradient (or blend) weighted to the area I wished to adjust then "Load Selection From Alpha" to modify the brightness and contrast smoothly to the right side. I'm new to Affinity, which I love, and can't seem to get this same affect accomplished. Any suggestions?

[stokerg]

Hi Sandy47 and Welcome to the Forums,

This should be possible but do you happen to have an example?

In theory you would want to use a B&W adjustment, set the sliders accordingly, merge visible then rasterise that merged layer to a mask.  But if you can provide an example, there might be a better way to get the same results  

[Sandy47]

Thanks for the response. Attached is an explanation I hope will help.

[Dazzler]

You can achieve the same type of thing without using an extra channel. If you set up an adjustment layer to adjust the levels  (or whatever) you can then use the gradient tool directly on the adjustment layer to make it affect the picture in different amounts according to the gradient. It's very a very similar technique to what you are currently doing in PS, just with a hidden channel built into the adjustment layer. You can also paint onto adjustment layers and the effect is fairly identical to painting on a channel in PS.

[Sandy47]

Many thanks! I had tried something similar I thought, but I'll give this a crack.

[Sandy47]

I just achieved the effect required with your expert guidance. Again, many thanks!