HDR: Possible to do it in Acorn?

Acorn
1

(I’m a new Acorn user, so apologies in advance for what might be a dumb question.)

I don’t find “HDR” in Acorn’s documentation, so I’m wondering if there might be a way to do basic HDR processing using Acorn’s tools? For example, if I have 3 RAW static landscape-type photos (taken with camera locked-down on tripod), one slightly underexposed, one “normal” exposure, and one slightly over-exposed, can I use Acorn to combine them to yield a high dynamic range image? Comments & suggestions appreciated.

EDIT: Ah, I found the “HDR Effect” tutorial on the Acorn docs page. It uses 1 image duplicated to multiple layers. Hmm … now I’m wondering how/if a similar procedure can be done using 3 differently-exposed images such as I describe above?

2

There’s no built in way to do this, but maybe if you posted some samples we might be able to figure out how to do it via blend modes?

3

Thanks for your reply. Blend modes might work. The question is how to make transparency based on luminance in Acorn? (“Luminance to alpha”) Example: Take 3 bracketed exposure photos (with camera on locked tripod) of a static daylight landscape scene. Make each a layer in Acorn. Make the “bright” pixels in the over-exposed photo transparent. Make the “dark” pixels in the under-exposed photo transparent. Make all but the medium-luminance pixels in the “middle” exposure photo transparent. Result should be a composite with wide dynamic range.

4

Luminance to Alpha would be a super cool feature! But sadly, it’s not something that’s built in today. I’ll add it to the todo list, because it could be kind of neat.