adding Adjustments to Pixel Layers in Designer

[bpedit]

I primarily work on iPad but it seems this issue is extant on Mac desktop too. I'm trying to add Adjustments to a pixel layer. This seems to work for a limited few adjustments, none useful to me. But adjustments like Levels, Curves, Contrast and most others produce no effect. If I export my pixel layer as a PNG then import it, the adjustments will work. Is there something I'm missing? The pixel layer and the imported PNG are both pixel based, it's unclear why one doesn't respond the the adjustments.

[NotMyFault]

We would need a screen recording and a copy of the actual file.

I observed general issues on iPad (M1) that rendering any changes stops completely after some time in Photo or Designer and you need to trigger a redraw by zooming, or even exit to app Home Screen to get redraws again.

[bpedit]

For the following a pixel layer has been created with some practice scribbling. That layer was exported, for comparison, as a JPEG and placed back into the AD file beneath the pixel layer. The video shows a Curves adjustment and its effects (or not) on the two objects.

The file:

pixelLayerAdjustmentTest.afdesign

[carl123]

Can you upload the test file again the forum says not found

[NotMyFault]

You have a pixel layer where you paint in black with low opacity. This creates a pixel layer where the modulation of lightness is created only over the alpha channel, not over the RGB channels. An adjustment on RGB has no effect because all color values are still zero.

When you export to JPG the pixel layer gets flattened and matted, meaning that any transparent areas get filled in white, and any semitransparent pixel get converted to shades of grey and full opacity.

Now that you have different non-zero color values, the adjustment layer cuts in as expected.

 

[Affinity Rat]

My interpretation of this is that you are apply a curves adjust (which as Notmyfault) says is an alpha or transparency adjustment to two layers.

In the case of the jpg, there is no transparency only shades of gray, representing partially transparent pixels.

In the case of the png, png retains transparency.

So performing a transparency operation on these two entirely different formats gives very different results.

The png already has transparency so the curves adjustment accentuates what is already there.

The jpg has no transparency so the curves adjustment adds some, but does not accentuate anything because nothing is transparent, only gray.

As black becomes transparent it appears gray, but this is not equivalent to alpha, so jpg and png very different representations. Obviously a layer below a png would be partially visible, but a layer below the jpg not, gray in jog does not equate to transparency.

My simple understanding. 😊

 

 

[bpedit]

Bingo! Thanks! So the solution is to paint down a base layer of white. Just tried that and it works.