Transparency to layer mask

[Medical Officer Bones]

Does anyone happen to know of an equivalent of Photoshop's "Layer Mask from Transparency" function in Affinity Photo? It converts the transparency of a layer to a layer mask, and removes the transparency from the original layer. In PhotoLine this is achieved by creating a new layer mask based on alpha. In Gimp there's the option to transfer a layer's alpha channel to a layer mask when a new layer mask is added to a layer with transparency.

To be clear, this function removes the transparency from the original layer, and transfers the alpha channel data to a layer mask.

It's a very basic option, and ought to be possible somehow in Affinity Photo, but so far I haven't been able to figure out how to accomplish this. Help is very much appreciated: I've been fiddling around for an hour now, and it's probably so obvious that I am looking past it.

[firstdefence]

You can go to the Channels Panel and right click on the Alpha Channel and select Create Mask Layer, this might be a starting point.

[Medical Officer Bones]

That was one of the things I tried, but to no avail: the original layer's transparency/alpha is maintained.

But your answer did motivate me to look once again, and I found a method/workaround:

1) switch to the channels panel, and right-click on the Pixel Alpha to create a new mask layer.

2) select the original layer and use the pixel alpha's Fill command to fill the alpha with pixels.

However, it is only a partial solution: I'd like to display the original pixel data.

[firstdefence]

One step closer, I'll have a ping-ping session in Photoshop and AFPhoto to see if anything clicks.

[firstdefence]

Affinity Photo doesn't seem able to create a transparency mask by transferring/removing an existing transparency on an image to the mask layer. It will create a mask using the transparency but the transparency will also remain on the image, enabling and disabling the mask layer also seems to affect the transparency's volume  which would back up the double transparency effect.

What I find a bit crazy is that you can right-click on the Alpha channel and select Fill and it will remove the transparency, so the ability is there it just doesn't transfer that ability to the mask, well as far as I can understand it at the moment.

If you create a blank mask and draw on it to get an area of transparency on the image, disabling the mask pretty much does what you want by removing the transparency.

[lepr]

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[Polygonius]

Why not using select-find transparancy and then creating a mask from that? 

[Medical Officer Bones]

@firstdefence Yes, that seems to be the case. It's quite a basic function, so I hope the devs will implement it at some point in the future.

For those who need an example, here's a file that demonstrates the problem:

When the transparency/alpha is transferred to a layer mask (or removed) this image pops up:

If someone happens to stumble on a method to accomplish this in Affinity Photo, I'd be grateful.

ps just noticed that in PhotoLine the brush tool can work directly with the alpha channel, and I can undelete the hidden parts of the image by painting over the transparent areas as well.

[lepr]

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[lepr]

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[Medical Officer Bones]

@owenr Thanks! I had tried it with another file, and assumed the fill command worked differently. Thanks for the help.