Adjustment affecting small areas outside selection

[PLShutterbug]

Have I found a bug in Photo? Or is it (more probably) a problem with what I'm doing?

I tried cropping my 560MB file so I could include a real .afphoto file you can manipulate, but apparently that's not possible (even with "Rasterize & Trim"). So all I have are screenshots.

This is an area of surf against a beach. I need to modify the surf without changing the beach, so I drew a selection on only the surf. Then I created a new Shadows/Highlights adjustment layer. When I increased the highlights I noticed that certain places near the edges of my selection were being affected as well - see the peanut-shaped white area and the light-tan area to their left.

Here is the same area, magnified a bit more, in selection refinement mode with the black matte option.

Looks to me like they are not part of the selection. yet when I change the shadows/highlights slider, those areas definitely change. Here is another look, using Overlay preview:

I've watched the Refining Selections video and thought I was following James' advice, but nothing I do ends up with those areas outside the effect of my adjustment slider.

What am I doing wrong?

[PLShutterbug]

I think I may have found a bug. I figured out how to get my file size down and created the small (relatively) file here.

Here is what I did:

1. Applied initial corrections in Develop persona including cropping the image.
2. Selected the water area, including fine-tuning the selection to exclude any beach - but I forgot one area (see 5 below).
3. Selected Layer, New Adjustment Layer, Shadows/Highlights to create a layer from my selection.
4. Moved the Highlights slider all the way to the right (200%).
5. Noticed that a small area near the upper right still included some beach, so again fine-tuned and used Alt-Drag to exclude that small area of beach.
6. Changes to the Highlights slider still changes the original selection area, not the modified area. I expected that when I changed the selection on which the layer is based that Affinity would now respect the new selection area for that layer, not continue to use a selection that no longer exists.

Attaching the file I used.

Is this intended behavior?

I note that by creating yet another new Shadows/Highlights layer from the changed selection, changes this this new area now affect only the updated selection area - apparently because that is the selection on which this new layer is based.

So: I created a selection, then a layer based on that selection. I changed the layer, then changed the selection.

Expected result: the layer effect is now limited to the new selection boundaries, whether those new boundaries are smaller or larger than before.

Actual result: changes to the layer continue to respect the old selection boundaries, even though those boundaries no longer exist and I can no longer manipulate them.

Even if this intended behavior, I submit that it is irrational and should be changed. If I see a selection for a layer, I expect that layer to work on what I see now, not some selection that may have existed earlier.

The_Journey_cropped.afphoto

[firstdefence]

Go to Select > Refine edges...

Uncheck the Matte Edges option and add either a bit of feather and or some smoothing.

 

[PLShutterbug]

Firstdefence, that will help as I create the selection. However the problem I am describing occurs AFTER selection is complete, and after I have created a layer based on that selection. If I apply an effect on the layer (ie, change highlights) and then change the selection, any further changes to the effects (For example I change the strength of that highlight from 150% to 100%) affect the original selected area, not the new one only. 

[carl123]

If you add a Shadows / Highlights  Adjustment Layer to an Image that already has a selection then the effect of that Adjustment layer is limited to the selection area on the image

The selection area is in effect "baked in" to the Adjustment layer and you cant then add to the selection you see on the screen and expect the Adjustment layer to adjust to the new selection automatically.

You would need to delete the Adjustment layer and readd it or paint with a white brush on the Adjustment layer over the newly added part of the selection.

Could this be what you are experiencing?

[PLShutterbug]

 

1 hour ago, carl123 said:

If you add a Shadows / Highlights  Adjustment Layer to an Image that already has a selection then the effect of that Adjustment layer is limited to the selection area on the image

The selection area is in effect "baked in" to the Adjustment layer and you cant then add to the selection you see on the screen and expect the Adjustment layer to adjust to the new selection automatically.

You would need to delete the Adjustment layer and readd it or paint with a white brush on the Adjustment layer over the newly added part of the selection.

Could this be what you are experiencing?

Carl, that is exactly what I'm experiencing. My complaint is that the effect of this is that if a user changes the selection boundaries or refines it in any other way, now they are looking at a selection that has no bearing on the adjustments made with the layer.

Either users should be prevented from changing the selection on which a layer is based, or the layer should respect any changes made and make the effect apply to the current selection boundary/refinements, not merely the original. To do anything else invites confusion, as I've experienced (and I'm sure others have as well). It reduces the usefulness of the product.

I will create a post in the "suggested features" section of the forums.

[R C-R]

What you are experiencing is the effect of the opacity mask that you have applied to the adjustment layer. As explained in this video tutorial, every adjustment layer has a built-in pixel mask. As it shows, you can edit the mask at any time by painting on the adjustment layer with a brush. Note that you can use the Paint Brush or Erase Brush tool with any of the brushes from the Brushes panel, with soft or hard edges, & the effect can vary from 100% opaque to 100% transparent.

Because you had a 'marching ants' pixel selection active when you first created the adjustment layer from the Background layer, the built-in mask automatically masked out everything outside that selection. In the Layers panel this is indicated by black & white areas on the adjustment layer's thumbnail:

As the video mentions, you can also option-click on the adjustment layer to see the mask isolated on the canvas. 

(If no pixel selection had been active when the adjustment layer was created, like in the video the thumbnail would have been all white, indicating that the mask was not being applied selectively.)

Because the built-in pixel mask is created as an inherent part of the adjustment layer, as @carl123 said it is always "baked in," just like how painting with a brush on a pixel layer is baked into that kind of layer. But like for that kind of layer, you can 'paint over' any part of it to change what it effects.