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Hello,

what would be the best way to remove alpha channel pixels from a layer or make them fully opaque?

In case I'm not making sense, here's an example: I add some red background and make a stroke with the brush over it with a green color, there's going to be red pixels of the background, green pixels of the brush and pixels that are green with alpha channel - how could I remove those with alpha channel or make them fully opaque?

Both GIMP and Photoshop have ways of doing this for whole document, layer or selection, I'm curious how one would do this in Affinity Photo, or even Affinity Designer. I could provide an example if needed.

Thanks!

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That would work in GIMP or Photoshop but the end result in Affinity Photo is, well, this:
image.thumb.png.7a5d3c43d81a6200a4a6f6e8207c4cdc.png
image.thumb.png.fafd7145769d520e4b2eb1998834c03e.png
and I cannot figure out why.

I would also prefer if I could find a way to maybe remove those alpha pixels rather than fill them with an opaque color, but either can work, I guess.

EDIT: Example in GIMP below.
image.thumb.png.ba974b3140119d03f87b42301e0710bb.png
image.thumb.png.d1603404f9c3fc84bac55d2b2cce5325.png

Edited by xuvvy
Added GIMP example
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I always find using blend ranges is really quick and easy:

Daz1.png

Mac Pro Cheese-grater (Early 2009) 2.93 GHz 6-Core Intel Xeon 48 GB 1333 MHz DDR3 ECC Ram NVIDIA GeForce GT 630 - 2 GBUgee 19" Graphics Tablet Monitor Mac OS Mojave 10.14.6

Affinity Designer, Photo and Publisher 1.9.2 + Illustrator CS5 / VectorStyler mainly for Vector distortion workarounds + InDesign CS5 for multipage spread jobs with Slug + ImageVectoizer / Vectorize for raster to vector conversions

www.bingercreative.co.uk

 

 

 

 

 

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Now that I've tried it a few times, both techniques almost work. The issue is that alpha-channel pixels still persist, while I would like all alpha channel pixels to either be removed or turned fully opaque and I haven't yet found a good way of doing so in Affinity Photo. I've found the 'solution', though, it's at the bottom.

In your example as well, @telemax, most transparent pixels are removed, but not all.
image.thumb.png.66ee1cf3bf906b88cabdeedce8496099.png
image.thumb.png.ea96f7d140e0d95d3f085afdc64dfa1e.png

There is no denying that the latter is cleaner, less alpha pixels, but there's still alpha pixels for some reason and I cannot figure out why. Here is zoomed in:
image.thumb.png.0303dadcdc911bcde96b994bc0ee3ba3.png

The solution to this, I found, is to just use the fill tool on the pixel layer with the mask layer being nested.
image.thumb.png.becfc2fcc033020cc1a6f4d2e8e73d16.png

If anyone has any simpler, better or cleaner solution, I'm all ears! :)

Edited by xuvvy
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15 hours ago, xuvvy said:

The issue is that alpha-channel pixels still persist

This is really easy to do using blend ranges:

 

Daz1.png

Mac Pro Cheese-grater (Early 2009) 2.93 GHz 6-Core Intel Xeon 48 GB 1333 MHz DDR3 ECC Ram NVIDIA GeForce GT 630 - 2 GBUgee 19" Graphics Tablet Monitor Mac OS Mojave 10.14.6

Affinity Designer, Photo and Publisher 1.9.2 + Illustrator CS5 / VectorStyler mainly for Vector distortion workarounds + InDesign CS5 for multipage spread jobs with Slug + ImageVectoizer / Vectorize for raster to vector conversions

www.bingercreative.co.uk

 

 

 

 

 

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