Apply Image to Layer Mask in AP

[webb]

I would like to apply an image (say, the green channel) to a layer mask, but cannot figure out how to do so.

 

For example, one common trick in Photoshop is to add an adjustment layer such as Curves, set its blend mode to Mulitply, and add a blurred version of the image itself as a mask (either a grayscale version of the image or one of the channels like Green.)  This maneuver often results in richer colors.

 

In Photoshop, you simply do what I just described: add an adjustment layer, set its blend mode to Multiply, add a layer mask, highlight it, and apply the image to the mask (Image -> Apply Image.) The Photoshop default for Apply Image is a grayscale version of the image, but you can choose a color channel instead if that more appropriate. You can tell that the mask has an effect because the adjustment layer set to Multiply shows a very dark version of the image, but adding the mask (and blurring it) brings it back to something that looks normal.

 

I am unable to figure out how to accomplish this in AP. I add a mask to a Curves adjustment layer, highlight it, bring up the Filter->Apply Image dialog box, drag the Green channel (or other channel, or the background layer) to the dialog box, but it seems to have no effect. I also tried "Use Current Layer as Source" with the same result. I just keep seeing the layer that was darkened by setting the layer's blend mode to Multiply.

 

This is not the only reason to want to add a grayscale version of the image or or color channel as a layer mask, but I describe it here as a reproducible example. 

 

So, how do I apply an image to a layer mask?

 

    --Webb

[James Ritson]

Hey Webb, there are a couple of aspects to my reply so I've tried to split them up! Hope it all makes sense:

 

 

Firstly, you needn't add a mask layer to your adjustment layer - it has its own mask to begin with, filled with pure white (i.e. fully opaque). Therefore, any mask manipulations you can just apply directly to the adjustment layer rather than having to create a nested mask layer.

 

Secondly, you can use Apply Image on the adjustment layer and drag your Background pixel layer onto the dialog, then check Equations to enable channel mixing, but you won't get the result you're after this way - it'll just be a greyscale version of the image applied as a mask. Substituting/swapping the channels doesn't seem to work, so I'll enquire as to whether there's a way to improve this.

 

 

The approach for this in Affinity Photo would be as follows:

1. Select your Background pixel layer (or whatever you've named your source layer that you want to use).
2. On the Channels panel, right click the desired colour channel (eg Background Green) and choose Create Spare Channel.
3. Add your adjustment layer, set the blend mode and tweak its parameters etc.
4. On the Channels panel, right click the new Spare Channel and choose "Load to Adjustment Alpha".

If you want to further manipulate the mask, you can just add filters directly to the adjustment layer. For example, you can use Filters>Blur>Gaussian Blur to soften the mask. Don't forget you can Alt/Option click the mask to isolate and preview it.

 

I'll record a short video and put it up here as it's a quiet afternoon  ;)

[James Ritson]

OK, quick video to show a couple of different ways of what you're after: https://www.youtube.com/watch?v=ozlfwI3HngI

[webb]

Thanks, both techniques worked like a champ. Still getting used to masks being available directly in adjustment layers.

[webb]

I also figured out that I can left-click on the green channel,  "Load to Pixel Selection", add a curves layer (automatically adding the selection as a mask), apply blur, and I'm in business.  Cool!

 

Just to press my luck: is there any way to apply curves to the mask itself? 

[Rob123456789]

On 22/12/2016 at 3:51 PM, James Ritson said:

OK, quick video to show a couple of different ways of what you're after: https://www.youtube.com/watch?v=ozlfwI3HngI

The video is no longer available - can you upload it again as I would like to see this

[kaffeeundsalz]

On 12/22/2016 at 9:04 PM, webb said:

Just to press my luck: is there any way to apply curves to the mask itself? 

 

Yes. Nest a Curves adjustment inside the mask as a child layer. Then, in the Curves dialog, choose "Alpha" from the channels dropdown list.

[dryfly52]

The video is no longer available which does not help! 

[jay27flow]

You know, in the last 2 hours i tried to simple start to mask out some hair by using channels but i never even got a grayscale image working as a mask which is pretty annoying. I've watched tutorials, searched in google etc, but nothing. It's a fkcin disappointment i just can't belive what's happening, i'm this dumb or just using this program is so not intuitive? Or is it a bug?? 
Finally i've recorded a video. Can somebody tell me what's going on?
 

1. I demonstrate using simple mask layers...it works with brush

2. I try to use a grayscale image as mask which i made from the red channel..it DOESN't WORK

3. Then a pathetic struggling starts to get rid of that 'mask layer'.. 

4. So finally, i show you what would be the way i would like to use it (we are at 2:07 in the video): I create a curves adjustment layer. I drop it on the grayscale image, under the name, to have the effect only that layer, then i drop the whole thing to the image, on the thumbnail, to convert it to a layer mask. Of course it still doesn't working and at this point i can't even reach the adjustment layer again...

I tried lot's of things, like create a mask for the color image with the mask button, then ctrl+c the grayscale image, then alt+click on the mask then ctrl+v but also doesn't work.

2 hours for my life and my nerve system is in pieces.

So please somebody tell me why this **** can not mask this ******* image???

PS: I'm aware of brush selections, refining masks and other techniques, i'm asking EXACTLY what i'm asking and not interested in 'other solutions'. 

Thank you!

[kaffeeundsalz]

1. Good.

2. Instead of  "Create Grayscale Layer", use "Create Mask Layer" directly below in the channels panel. Alternatively, right-click you grayscale pixel layer and choose "Rasterize To Mask".

3. For a nested layer, click its thumbnail once to deselect its parent layer. Then, drag it anywhere, but also from the thumbnail. Or hit the delete key.

4. This will work in Affinity Photo, but you need to make sure that a) the Curves adjustment is nested directly below your mask layer and b) you choose "Alpha" from the channels dropdown in the Curves dialog before editing the curve.

[jay27flow]

Thank you very much kaffeeundsalz! 
All the informations are welcome and useful you wrote, especially the last one which i could NEVER figured out by alone! It is such a big help for me!!
 

https://giphy.com/gifs/3oEdva9BUHPIs2SkGk

[jay27flow]

May i ask one more? In this video you can see i use your previous tips. (Until 0:55) Everything is working fine, until i add the Curves adjustment layer to the mask BEFORE i make it nested. At 1:22 you can see i just can't attach the curves adjustmen layer to the mask. Do you now how to do it except the workaround where i move the mask out, attach the curves and move the whole thing back?
 

 

[kaffeeundsalz]

Hi @jay27flow,

yes, this is a bit tricky because nesting in Affinity Photo does not work for more than one level, meaning that you can't nest a layer inside a layer that is already nested. In your case, you would do the following:

1. Nest the mask layer.
2. Nest the curves adjustment.
3. Drag the mask layer next to the parent layer (to the vertical blue bar, just as if you'd want to nest it again) to get it above the curves adjustment.

If you can, nest the curves adjustment first and then the mask. This saves step 3 because the layers are already correctly ordered. With this layer setup, the curves adjustment will affect the mask properly, even though they are now both at the same level. The cool thing about this is that you can use the same curves adjustment to modify the parent layer as well with the other channel controls.

The Affinity forums are usually quite responsive, so just hit reply if more questions arise.

Cheers
kaffeeundsalz

[jay27flow]

Thank You!  I love this program, the only thing which i don't prefer this complicated mask behavior/layer behavior. In PS i do not need to convert something to a pixel layer, or convert a grayscale image to a mask layer etc just handling masks way easier. But... they started that subscription style, so i leave them and bought a copy of Affinity Photo. It worked fine in many situations and the price is more than correct. And maybe with time i get used to this wierd layer masking system also. 

You helped me a lot with that alpha curve thing. It is a pretty weak solution in this program, very confusing (these types, for example in this case i have a grayscale PIXEL layer which is a MASK but in the adjustment layer it is an ALPHA, so nest togeather some things and tell me which one is which, how the data flows) etc) and the problem it is not working for other adjustment layers, for example the Brightness layer doesn't have a menu to choose 'Alpha'. Whatever. I try to learn it...

I wish someday a node based photoshop like program will be developed, with a good price and permanent license...like Nuke or Blender's compositor, but with tools like content aware fill (inpaint) and all the other good stuff. The Foundry's Mari is the nearest thing to what i'm talking about, but it's 3D and PS has way more tools....whatever. This is a dream and i live in the present...

[kaffeeundsalz]

I agree that layer masking and alpha channel handling need to get much simpler and more consistent in Affinity Photo. In case you're interested, there's an extensive discussion about this with already over a hundred replies going on here:

The upcoming 1.9 updates will have at least some improvements in this area (e.g. we can expect more filters and tools to work on mask layers), but it's still a long way to go. From my own experience, I can say that you probably will get used to it indeed.

[jay27flow]

Wow, sounds exciting!

[jay27flow]

Uhh, i've checked the thread you've linked... at least i know i'm not the only one