Hi,
The last version of photoshop I used was CS4. There was this neat trick where I clicked Option-command-2 and I got a selection based on luminosity. I could invert it if needed. Then I did a curves layer, did nothing with the curves, just blended in screen mode if I wanted to bring out dark areas. It was an easy and quick fix for unintentionally backlit photos, as a better alternative to the dodge/burn tool. Is there anything like that in Affinity? I found ways to do mask based on highlights and shadows, but it is not as graduated as this option. Please help. It is the only feature I miss from PS.