smadell

Based on a recent thread started by user Steps, I have finalized and am attaching a macro called "Graphic Novel Effect." It is similar to the "Paint by Numbers" macro I created a while back, but offers better control of the black outlines that are needed in a cartoon or a graphic novel illustration.
The attached file is a macros category (not a single macro) and can be imported through the Affinity Photo Library panel. Once inside Affinity Photo, the category contains a single macro which can be moved into a different category (by dragging it) if desired. Since it is provided as a category, it can also be imported into the iPad version of AP.
When you use the macro, it creates a number of layers inside a group (which can be turned on and off to show or hide the effect entirely). The user is presented with 5 options in a dialog:
1) Posterize - How Many Colors?
The macro is preset to 5 color levels, but anywhere between 4 and 6 generally gives a decent result.
2) Outlines - Adjust Black [line thickness]
This option is preset to 50%, but changing the value will make the black outlines more or less prominent.
3) Outlines - Adjust White [fill smoothness]
This option is preset to 90%. Changing the value will affect the fill (inside the outlines). Keep the value above the value set in option #2 (line thickness).
4) Finish - Adjust the Brightness
5) Finish - Adjust the Contrast
These are preset to Brightness = -15% and Contrast = +30%. Changes made here will have the obvious results, and should be considered a finishing touch.
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  * 
As always, I am one person with one computer and have not tested this in every possible scenario. Try it and, if you like it, keep it and enjoy it. This forum has provided me with so many good ideas and answers to questions; this macro is another attempt to “pay it forward.”
Graphic Novel Effect.afmacros

As another alternative, here's a macro that I just posted a couple of moments ago.
 

Based on a recent thread started by user Steps, I have finalized and am attaching a macro called "Graphic Novel Effect." It is similar to the "Paint by Numbers" macro I created a while back, but offers better control of the black outlines that are needed in a cartoon or a graphic novel illustration.
The attached file is a macros category (not a single macro) and can be imported through the Affinity Photo Library panel. Once inside Affinity Photo, the category contains a single macro which can be moved into a different category (by dragging it) if desired. Since it is provided as a category, it can also be imported into the iPad version of AP.
When you use the macro, it creates a number of layers inside a group (which can be turned on and off to show or hide the effect entirely). The user is presented with 5 options in a dialog:
1) Posterize - How Many Colors?
The macro is preset to 5 color levels, but anywhere between 4 and 6 generally gives a decent result.
2) Outlines - Adjust Black [line thickness]
This option is preset to 50%, but changing the value will make the black outlines more or less prominent.
3) Outlines - Adjust White [fill smoothness]
This option is preset to 90%. Changing the value will affect the fill (inside the outlines). Keep the value above the value set in option #2 (line thickness).
4) Finish - Adjust the Brightness
5) Finish - Adjust the Contrast
These are preset to Brightness = -15% and Contrast = +30%. Changes made here will have the obvious results, and should be considered a finishing touch.
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  * 
As always, I am one person with one computer and have not tested this in every possible scenario. Try it and, if you like it, keep it and enjoy it. This forum has provided me with so many good ideas and answers to questions; this macro is another attempt to “pay it forward.”
Graphic Novel Effect.afmacros

If memory serves me correctly (and it frequently does not!) there was a suggestion along the way that the "Looks Persona" would be the equivalent of a Filter Gallery, or an Artistic Filter kind of mode. The Looks Persona has been listed in the Affinity Photo Roadmap for as long as I can remember, but it seems to have gotten very little "air time." Maybe what you're asking for actually IS on the docket, but hasn't arrived yet.

If you're not completely satisfied with that effect, you might want to check out a macro I posted a while ago. It's called "Paint by Numbers" and it gives a somewhat different result.
https://forum.affinity.serif.com/index.php?/topic/83173-paint-by-numbers/&tab=comments#comment-438291

I am attaching an Affinity Photo macro that turns a photo into a “Paint by Numbers” image. The attached file is a macros category, and should be imported through the “hamburger” menu at the top right of the Library panel. The category can also be imported into the iPad version of Affinity Photo, although there is one important limitation (more on this later).
When you use the macro, it creates a Group called “Paint by Numbers Effect.” All of the changes are inside of this group, so you can turn it on and off simply. Once you look inside the group, you will see multiple layers. From bottom to top, these are:
1) Original Image - Merge Visible
This is a “merge visible” version of your photo. It includes all of the editing you may have done up until that point.
2) Posterization Adjustment
This is a Posterize adjustment layer, and is meant to reduce the number of colors/tones used in the effect.
3) Outlines
This is a separate layer, created (in part) by using a Detect Edges filter. It provides outlines for the areas of color. This mimics the outlines that were present on the Paint by Numbers boards we used as kids.
4) Normalize Colors
This is a copy of the original Merge Visible image, and has its blend mode set to Color. This is used to reset the posterized colors to more natural ones.
5) Adjust Brightness & Contrast
This is a finishing adjustment, and can provide a better final effect.
* * * * * * * * * * * * * * * * * * * *
Once you click the macro, you will be presented with a default version of the effect. A dialog box allows you to set a number of parameters. As you change each of these parameters, the Paint by Numbers effect is updated. You are asked:
Posterize - How Many Colors?
The default value is 4, but values between 3 and 6 generally give good results. If your image is a portrait, judging the final result by looking at what the different values do to the subject’s face is a good idea.
Outlines - Adjust the Opacity
The default is 50%. Adjust this upward to make the outlines more prominent; adjust it downward to make the outlines less obvious. Set to 0 to make them go away entirely.
Finish - Adjust the Brightness
Finish - Adjust the Contrast
The default is 10% brightness, and 20% contrast. Adjust these up or down to give you final effect the desired finish.
When you click Apply, the effect is finalized. Obviously, you can manually change any of the settings after the fact. However, you should know that while the number of posterization levels for the image is non-destructive, the originally chosen number is also used to create the outlines, and this is a destructive change. Although you can change the posterization level after the fact, it is not advisable to do this. The outlines might no longer line up with the individual areas of color.
Also, for some reason, the iPad version of Affinity Photo handles the macro pretty well but will not allow you to change the number of posterization levels before finalizing the effect. It is baked in at 4 levels. You can change this after the fact, but (as above) the number of levels in your posterized image may not match your outlines very well.
Here is the macro in action. The original image is top left; the parameters dialog is shown in its default state, and then changed during the course of the macro; the final effect is shown top right

As always, I am one person with one computer and have not tested this in every possible scenario. Try it and, if you like it, keep it and enjoy it. This forum has provided me with so many good ideas and answers to questions; this macro is my attempt to “pay it forward.”
[Note: Credit where credit is due. I am indebted to Dave Straker, whose recent YouTube video gave me some excellent ideas for this macro. Dave’s channel is called “InAffinity,” and is a steady source of helpful information. Thanks, Dave!]
 
Paint by Numbers.afmacros

Steps...
Here's the macro you wanted. I named it "Dave's  Cartoon Effect" in order to give credit to Dave Straker who, after all, came up with the process. The only thing I changed was to set the blend mode of both the inverted outline pixel layer and the live Gaussian Blur layer to Color Burn. I also set the default blur to 0.5 pixels, as this was a bit more to my own liking. As you'll see, though, it is user-customizable. I didn't put in a step to alter the opacity, but clearly you can do that after the fact.
Note that I've made this an importable macros category, and not a single macro. When imported (through the Library) this will become a new category with a single macro in it. This will also let the macro be imported into the iPad version, if you want.
Dave Straker's Cartoon Effect.afmacros.zip

Steps...
Here's the macro you wanted. I named it "Dave's  Cartoon Effect" in order to give credit to Dave Straker who, after all, came up with the process. The only thing I changed was to set the blend mode of both the inverted outline pixel layer and the live Gaussian Blur layer to Color Burn. I also set the default blur to 0.5 pixels, as this was a bit more to my own liking. As you'll see, though, it is user-customizable. I didn't put in a step to alter the opacity, but clearly you can do that after the fact.
Note that I've made this an importable macros category, and not a single macro. When imported (through the Library) this will become a new category with a single macro in it. This will also let the macro be imported into the iPad version, if you want.
Dave Straker's Cartoon Effect.afmacros.zip

Instead of setting “opacity” to 10% (which will only build up with repeated strokes, each after lifting your finger) leave the opacity at 100% and set the “flow” to 10%. This should do what you’re after.

Today, let’s have fun with Gradient Maps…
Gradient Maps are a great way to color grade photos, since they map dark, light, and midtone values according to a pre-defined gradient. This can easily define a “look” for photos that might otherwise be hard to accomplish.
Although I am not a user of Photoshop, our “arch rival” has a wonderful group of gradient maps called “Photographic Toning” that are specifically designed to color grade photos. Although you have to drill down through a few panels and dialog boxes to find them (and you sort of have to know they’re there in the first place) they are a truly nice addition. Also, they are easily obtained by anyone.
But, as they say, there’s the rub. Affinity Photo cannot import Photoshop gradient maps. Affinity Photo can store pre-defined gradients in the Swatches studio, but for some unknown reason the stored gradients are not available from the Gradient Map studio panel. Gradient Maps can be stored as presets, and can be chosen from the Adjustments panel, but I don’t believe they can be easily exported from one computer and brought into a different one.
So… after a long couple of days of transcription, I have created a set of Macros that apply each of the 38 Photographic Toning gradient maps. Since macros are easy to store, and to share, I am making them available for anyone who wants them.
There are actually 2 sets of Macros included - each as an easy-to-import Category from the Library panel. The first group of Macros is called “Photographic Toning Gradients” and these are named according to the gradient map they apply. Each macro creates a Gradient Map layer, applies the appropriate color values, and names the layer according to the gradient map it applied. The second set of macros is called “Photographic Toning Gradients - reduced.” This category also applies the gradient maps in a similar fashion, but then reduces the opacity of the layer to 30%. This reduces the effect of the Gradient Map, and produces a much subtler effect.
Here is an image that shows the full-strength versions of all 38 gradient maps.

And here is a photo to which I’ve applied a full-strength gradient map, and also a reduced-strength gradient map.

These macro categories are included in the ZIP file attached to this post, along with a Letter sized JPG that includes samples of the gradient maps. Also included in the ZIP file is another macro category that includes one more macro. It’s called “Obama Hope Poster” and, as you might have guessed, it turns any photo into an Obama Hope-style poster. Just because…
Please enjoy them!
Photographic Toning Gradient Maps.zip

I just this minute found a post on the DxO forum, basically titled “Critical Bug in PhotoLab 2 - sRGB profile missing on export.” I’ve included a link to the post below. However, this seems to be a very serious bug in version 2 of PhotoLab, and it explains the problems that you’re all having.
https://feedback.dxo.com/t/critical-bug-in-photolab-2-missing-srgb-icc-profile-during-export/8347

I am attaching an Affinity Photo macro that turns a photo into a “Paint by Numbers” image. The attached file is a macros category, and should be imported through the “hamburger” menu at the top right of the Library panel. The category can also be imported into the iPad version of Affinity Photo, although there is one important limitation (more on this later).
When you use the macro, it creates a Group called “Paint by Numbers Effect.” All of the changes are inside of this group, so you can turn it on and off simply. Once you look inside the group, you will see multiple layers. From bottom to top, these are:
1) Original Image - Merge Visible
This is a “merge visible” version of your photo. It includes all of the editing you may have done up until that point.
2) Posterization Adjustment
This is a Posterize adjustment layer, and is meant to reduce the number of colors/tones used in the effect.
3) Outlines
This is a separate layer, created (in part) by using a Detect Edges filter. It provides outlines for the areas of color. This mimics the outlines that were present on the Paint by Numbers boards we used as kids.
4) Normalize Colors
This is a copy of the original Merge Visible image, and has its blend mode set to Color. This is used to reset the posterized colors to more natural ones.
5) Adjust Brightness & Contrast
This is a finishing adjustment, and can provide a better final effect.
* * * * * * * * * * * * * * * * * * * *
Once you click the macro, you will be presented with a default version of the effect. A dialog box allows you to set a number of parameters. As you change each of these parameters, the Paint by Numbers effect is updated. You are asked:
Posterize - How Many Colors?
The default value is 4, but values between 3 and 6 generally give good results. If your image is a portrait, judging the final result by looking at what the different values do to the subject’s face is a good idea.
Outlines - Adjust the Opacity
The default is 50%. Adjust this upward to make the outlines more prominent; adjust it downward to make the outlines less obvious. Set to 0 to make them go away entirely.
Finish - Adjust the Brightness
Finish - Adjust the Contrast
The default is 10% brightness, and 20% contrast. Adjust these up or down to give you final effect the desired finish.
When you click Apply, the effect is finalized. Obviously, you can manually change any of the settings after the fact. However, you should know that while the number of posterization levels for the image is non-destructive, the originally chosen number is also used to create the outlines, and this is a destructive change. Although you can change the posterization level after the fact, it is not advisable to do this. The outlines might no longer line up with the individual areas of color.
Also, for some reason, the iPad version of Affinity Photo handles the macro pretty well but will not allow you to change the number of posterization levels before finalizing the effect. It is baked in at 4 levels. You can change this after the fact, but (as above) the number of levels in your posterized image may not match your outlines very well.
Here is the macro in action. The original image is top left; the parameters dialog is shown in its default state, and then changed during the course of the macro; the final effect is shown top right

As always, I am one person with one computer and have not tested this in every possible scenario. Try it and, if you like it, keep it and enjoy it. This forum has provided me with so many good ideas and answers to questions; this macro is my attempt to “pay it forward.”
[Note: Credit where credit is due. I am indebted to Dave Straker, whose recent YouTube video gave me some excellent ideas for this macro. Dave’s channel is called “InAffinity,” and is a steady source of helpful information. Thanks, Dave!]
 
Paint by Numbers.afmacros

I can't speak to most of your suggestions, but one of them is already there. If you want your Live Filter layers to appear as an additional layer (above the currently selected one) rather than as a child of the selected layer, use the Assistant (from the Toolbar) to make that choice. See below:

If you look carefully at the PhotoWhoa site, you should notice that all of the presets are described as an "Affinity Presets LUTS Collection." This pretty much defines how you'll end up using them.
Affinity Photo can use "color lookup tables" (otherwise known as CLUT's or LUT's) and these are fairly commonly used to "color grade" images or video. Basically, if you start with an image and then alter it with one or more Adjustment layers, you can then choose "Export LUT..." to form an external file that encapsulates all of the adjustments you made. Basically, a color lookup table is simply that - it lets you start with a bunch of pixels (your photograph) in which each pixel has a defined color, then the LUT changes each of the colors to a pre-defined "other" color according to the entries in the lookup table. It's a simple substitution scheme, which goes something like "wherever there's a pixel with this color [R255,G0,B0] put in a something else, like [R240,G100,B100]." And, it does that for each triplet combination of Red, Green, and Blue in your photo.
The up side to using a LUT is that it is simple, and boils down to an all-in-one color grade change. The down side is that the LUT does not add the component Adjustment Layers, so you can't really tweak the components afterward (except by adding more adjustments and filters, etc.)
To use your MegaPresets files, simply put the collection of folders somewhere convenient. I'm not from the Windows side, but I don't think there's a specific place they need to be. Once you have a photo in Affinity Photo, add an adjustment layer by choosing "LUT..." from the Layer>New Adjustment Layer submenu, or by choosing it from the icon at the bottom of the Layers panel. The LUT dialog box will open.

Click on the button called "Load LUT" and you will be able to navigate to the folder(s) containing your presents. Choose the one you like. Your photo will have one extra adjustment layer, labelled LUT, and the color lookup changes dictated by the LUT file will have been applied. (You may want to change Blend Modes, opacity, and so forth on the LUT adjustment layer to further refine the color grading.

If you look carefully at the PhotoWhoa site, you should notice that all of the presets are described as an "Affinity Presets LUTS Collection." This pretty much defines how you'll end up using them.
Affinity Photo can use "color lookup tables" (otherwise known as CLUT's or LUT's) and these are fairly commonly used to "color grade" images or video. Basically, if you start with an image and then alter it with one or more Adjustment layers, you can then choose "Export LUT..." to form an external file that encapsulates all of the adjustments you made. Basically, a color lookup table is simply that - it lets you start with a bunch of pixels (your photograph) in which each pixel has a defined color, then the LUT changes each of the colors to a pre-defined "other" color according to the entries in the lookup table. It's a simple substitution scheme, which goes something like "wherever there's a pixel with this color [R255,G0,B0] put in a something else, like [R240,G100,B100]." And, it does that for each triplet combination of Red, Green, and Blue in your photo.
The up side to using a LUT is that it is simple, and boils down to an all-in-one color grade change. The down side is that the LUT does not add the component Adjustment Layers, so you can't really tweak the components afterward (except by adding more adjustments and filters, etc.)
To use your MegaPresets files, simply put the collection of folders somewhere convenient. I'm not from the Windows side, but I don't think there's a specific place they need to be. Once you have a photo in Affinity Photo, add an adjustment layer by choosing "LUT..." from the Layer>New Adjustment Layer submenu, or by choosing it from the icon at the bottom of the Layers panel. The LUT dialog box will open.

Click on the button called "Load LUT" and you will be able to navigate to the folder(s) containing your presents. Choose the one you like. Your photo will have one extra adjustment layer, labelled LUT, and the color lookup changes dictated by the LUT file will have been applied. (You may want to change Blend Modes, opacity, and so forth on the LUT adjustment layer to further refine the color grading.

Today, let’s have fun with Gradient Maps…
Gradient Maps are a great way to color grade photos, since they map dark, light, and midtone values according to a pre-defined gradient. This can easily define a “look” for photos that might otherwise be hard to accomplish.
Although I am not a user of Photoshop, our “arch rival” has a wonderful group of gradient maps called “Photographic Toning” that are specifically designed to color grade photos. Although you have to drill down through a few panels and dialog boxes to find them (and you sort of have to know they’re there in the first place) they are a truly nice addition. Also, they are easily obtained by anyone.
But, as they say, there’s the rub. Affinity Photo cannot import Photoshop gradient maps. Affinity Photo can store pre-defined gradients in the Swatches studio, but for some unknown reason the stored gradients are not available from the Gradient Map studio panel. Gradient Maps can be stored as presets, and can be chosen from the Adjustments panel, but I don’t believe they can be easily exported from one computer and brought into a different one.
So… after a long couple of days of transcription, I have created a set of Macros that apply each of the 38 Photographic Toning gradient maps. Since macros are easy to store, and to share, I am making them available for anyone who wants them.
There are actually 2 sets of Macros included - each as an easy-to-import Category from the Library panel. The first group of Macros is called “Photographic Toning Gradients” and these are named according to the gradient map they apply. Each macro creates a Gradient Map layer, applies the appropriate color values, and names the layer according to the gradient map it applied. The second set of macros is called “Photographic Toning Gradients - reduced.” This category also applies the gradient maps in a similar fashion, but then reduces the opacity of the layer to 30%. This reduces the effect of the Gradient Map, and produces a much subtler effect.
Here is an image that shows the full-strength versions of all 38 gradient maps.

And here is a photo to which I’ve applied a full-strength gradient map, and also a reduced-strength gradient map.

These macro categories are included in the ZIP file attached to this post, along with a Letter sized JPG that includes samples of the gradient maps. Also included in the ZIP file is another macro category that includes one more macro. It’s called “Obama Hope Poster” and, as you might have guessed, it turns any photo into an Obama Hope-style poster. Just because…
Please enjoy them!
Photographic Toning Gradient Maps.zip

Hey, WeiPhotoArts…

First, the simple stuff. Yes, one of your responses in the original Luminosity Selections post was the reason I started thinking about the second set of macros. And, in response to your question about creating, naming, and utilizing additional channels, AP macros can create additional channels and use them, but I have not found a way to (i) rename them, (ii) select them based on name, or (iii) delete them based on name. Any new channel you create in a macro will be called “Spare Channel.” As far as utilizing the Background Alpha channel, I have simply not mastered that one.

*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *

About the macros themselves. Both the Luminosity Selections and the Luminosity Blend Options… macros are based on altering the Blend Options of the layers to which they are applied. The only real difference is that the Luminosity Selections macros apply blend options based on the luminosity of the selected pixel layer; the Luminosity Blend Options for Adjustments macros apply blend options based on the layers underneath the selected one.

Think about it this way. Open a photo and you have created a pixel layer called “Background.” Now apply an adjustment layer, which sits above the pixel layer. The Luminosity Selections macros can be applied to the Background (pixel) layer; the Luminosity Blend Options for Adjustments macros can be applied to the Adjustment Layer.

Both sets of macros use the same values in the Blend Options panel - the difference is only whether they evaluate the Source Layer (the left graph) or the Underlying Composition (the right graph).

*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *

As to my choice of values in the Blend Options graphs, my thinking was generally as follows.

1) Luminosity based selections/masks apply differing amounts of selection based on the whiteness or blackness of any given pixel. If you accept that premise, then every pixel in an image should have a corresponding amount of selection.

2) In the simplest case (Lights 1), the graph is a straight line. Pure black is 0% selected, Pure white is 100% selected, Neutral Gray (50% gray) is 50% selected.

3) In creating a curve for Lights 2, I applied the equation y = (x*x), where y is the percentage of selection and x is the percentage of luminosity. So, Pure black is still 0% selected (since y = (0 * 0)) and Pure White is still 100% selected (since y = (100% * 100%)). However, Neutral gray is only 25% selected (since y = (50% * 50%)). Think of this as applying a luminosity selection, then applying it again.

4) Values for the Lights 3 and Lights 4 selections extend that same thinking. For instance, in Lights 3, neutral gray is selected (50% * 50% * 50%). The blend options curve for Lights 3 therefore has a point where 50% on the x axis (luminosity) has a corresponding value of 12.5% on the y axis (percent selection).

5) The Darks 1, 2, 3, and 4 curves are simply the inverse (mirror image) of the Lights curves.

6) The Midtones curves start with the assumption that Neutral Gray should be selected 100%. The other values include 0% selection for both Pure Black and Pure White. This results in a triangular selection with the top of the triangle at x=50% and y=100%.

7) The Midtones 1 curve, therefore, has a value of 50% selection (y axis) for both 25% luminosity and 75% luminosity (x axis). The Midtones 2 curve changes that to a 25% selection (50% * 50%) for these points. And so on…

*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *

As to your other concerns, I can only offer the following. First of all, I don’t own Photoshop and I have no experience with Tony Kuyper. I have applied my own logic to the construction of luminosity selections/masks, and have not relied on the work of others. As such, there may be differences in results. Second, my understanding is that Photoshop relies on “intersecting” selections, and this is done differently in Affinity Photo. A direct implementation of Photoshop methods may simply not be possible. AP is, in my estimate, the more elegant of the two.

*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *

Last, you suggest that your results differ when you use corresponding macros from the two sets. This should not be so, since the blend options curves are the same.

I started with a simple White to Black gradient.



I then applied the Darks 2 Luminosity Selection macro.



With that selection active, I added a Recolor adjustment (using the default value of pure red). This is the result I got.



Then, I started with the White to Black gradient again, added the Recolor Adjustment, and applied the Darks 2 Luminosity Blend Options for Adjustments macro with the Adjustment Layer selected. This is the result.



To my eye, the two results are exactly the same.

Hi Josie,
I worry that all of the threads you make end in someone making the work for you, I don't want you to ever feel like this forum is a place you can't ask for help it is and always will be a great learning resource for Affinity users. However I have noticed your threads typically revolve around similar issues which makes me worry that because people guide you step by step through whichever design it is you are trying to create not all of the information is taken on board. The techniques explained to you in this thread should be enough to create all of the designs shown above.
What I would ask is that instead of asking how to do something instead try creating it yourself and if you get stuck explain to us what you have tried and if possible provide a screenshot of your work so far. This would enable us to build upon the foundation of knowledge you already have instead of starting over with every thread. If you don't know where to start with a design like this I recommend taking a look at the tutorials V_Kyr suggested you look at here.
Thanks
Callum

Haitch...  I think there are a couple of answers to your questions. First, using an image to create the mask is, in essence, the definition of a Luminosity Mask. You can create one in a number of ways. The easiest is to hold down Command and Option (on a Mac) and click on the Layer thumbnail. This creates a luminosity selection, and you can click the Mask icon on the Layers panel to create a straight luminosity mask. You can Command-Option-Click and then Invert the selection to get the reverse type of mask (the one that protects highlights). Alternately, there are a number of users (myself included) who have posted Macros to create various types of luminosity selections and masks. You might want to try these:
https://forum.affinity.serif.com/index.php?/topic/27214-luminosity-masks/&tab=comments#comment-132021
https://forum.affinity.serif.com/index.php?/topic/30523-luminosity-masks-for-adjustment-filter-layers/&tab=comments#comment-149299
https://forum.affinity.serif.com/index.php?/topic/39420-luminosity-mask-visualization/&tab=comments#comment-196801
The other thing to know is that, as R C-R alluded to, you can't apply most adjustments and filters directly to a mask. While Photoshop seems to treat masks as editable greyscale images, Affinity Photo treats masks as pure Alpha Channels. As such, most of the standard adjustments can't be done to them directly. HOWEVER, you can apply a Levels adjustment or a Curves adjustment to a mask. Create a mask to be adjusted. Then create a Levels (or Curves) adjustment. Drag the new adjustment layer onto the Mask icon in the Layers panel. In the Levels (or Curves) adjustment, change the channel selection from "Master" to "Alpha." You can then apply the Levels or Curves to the Mask directly.
 

I have previously posted 2 sets of luminosity based macro sets. The first set worked on Image and Pixel layers, and created Luminosity Selections that could then be used to create masks, adjustments, filters, etc. They can be found here:

https://forum.affinity.serif.com/index.php?/topic/27214-luminosity-masks/

The second set of macros was meant to be used directly on Adjustment and Live Filter layers. These applied luminosity based Blend Options to adjustment and filter layers, based on the Image or Pixel layer(s) below the adjustment. They can be found here:

https://forum.affinity.serif.com/index.php?/topic/30523-luminosity-masks-for-adjustment-filter-layers/

Recently, a post from @danlhayes brought up the question of creating a greyscale representation of the luminosity selection. This would be similar to Option-clicking on a luminosity mask to see that mask in shades of grey. After (admittedly) quite a bit of trial and error, I’ve come up with a set of macros that will do just that. They are attached to this post.

*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  

To use the Luminosity Visualization macros, you should do the following:

1) You need to start with a Pixel or an Image layer selected. An embedded Affinity Photo document also seems to work.
2) Click on the macro you would like to represent as a greyscale image.
3) The macro will create a new Pixel layer with the name “LuminosityVisualization” and put it on the top of your layer stack.
4) You can get rid of the LuminosityVisualization layer by clicking on the macro named “Delete Visualization Layer.”

As always, some caveats:

5) You should always delete a previously created LuminosityVisualization layer before creating another one.
6) When you create a LuminosityVisualization layer, it will be placed at the top of the layer stack (so that any other layers you have placed over your Image/Pixel layer don’t confuse the visualization). If you delete the LuminosityVisualization layer and want to create another one, be sure to choose your Image or Pixel layer again.
7) These macros were created using the same Blend Options curves that I used in creating the first two sets of macros. As such, they are meant to be used together with those macros, and not with luminosity selections that may be available from other users.
8) As always, I am one person with one computer. I believe that these macros will work as I’ve stated, but I cannot possibly have tested every possible combination of situations. No guarantees are made; use them if you like them!
9) If you like the macros, they are yours. They are a “thank you” to everyone for helping me learn, and a request to “pay it forward” with continued generosity.
Luminosity Visualization.afmacros.zip

Haitch...  I think there are a couple of answers to your questions. First, using an image to create the mask is, in essence, the definition of a Luminosity Mask. You can create one in a number of ways. The easiest is to hold down Command and Option (on a Mac) and click on the Layer thumbnail. This creates a luminosity selection, and you can click the Mask icon on the Layers panel to create a straight luminosity mask. You can Command-Option-Click and then Invert the selection to get the reverse type of mask (the one that protects highlights). Alternately, there are a number of users (myself included) who have posted Macros to create various types of luminosity selections and masks. You might want to try these:
https://forum.affinity.serif.com/index.php?/topic/27214-luminosity-masks/&tab=comments#comment-132021
https://forum.affinity.serif.com/index.php?/topic/30523-luminosity-masks-for-adjustment-filter-layers/&tab=comments#comment-149299
https://forum.affinity.serif.com/index.php?/topic/39420-luminosity-mask-visualization/&tab=comments#comment-196801
The other thing to know is that, as R C-R alluded to, you can't apply most adjustments and filters directly to a mask. While Photoshop seems to treat masks as editable greyscale images, Affinity Photo treats masks as pure Alpha Channels. As such, most of the standard adjustments can't be done to them directly. HOWEVER, you can apply a Levels adjustment or a Curves adjustment to a mask. Create a mask to be adjusted. Then create a Levels (or Curves) adjustment. Drag the new adjustment layer onto the Mask icon in the Layers panel. In the Levels (or Curves) adjustment, change the channel selection from "Master" to "Alpha." You can then apply the Levels or Curves to the Mask directly.
 

Haitch...  I think there are a couple of answers to your questions. First, using an image to create the mask is, in essence, the definition of a Luminosity Mask. You can create one in a number of ways. The easiest is to hold down Command and Option (on a Mac) and click on the Layer thumbnail. This creates a luminosity selection, and you can click the Mask icon on the Layers panel to create a straight luminosity mask. You can Command-Option-Click and then Invert the selection to get the reverse type of mask (the one that protects highlights). Alternately, there are a number of users (myself included) who have posted Macros to create various types of luminosity selections and masks. You might want to try these:
https://forum.affinity.serif.com/index.php?/topic/27214-luminosity-masks/&tab=comments#comment-132021
https://forum.affinity.serif.com/index.php?/topic/30523-luminosity-masks-for-adjustment-filter-layers/&tab=comments#comment-149299
https://forum.affinity.serif.com/index.php?/topic/39420-luminosity-mask-visualization/&tab=comments#comment-196801
The other thing to know is that, as R C-R alluded to, you can't apply most adjustments and filters directly to a mask. While Photoshop seems to treat masks as editable greyscale images, Affinity Photo treats masks as pure Alpha Channels. As such, most of the standard adjustments can't be done to them directly. HOWEVER, you can apply a Levels adjustment or a Curves adjustment to a mask. Create a mask to be adjusted. Then create a Levels (or Curves) adjustment. Drag the new adjustment layer onto the Mask icon in the Layers panel. In the Levels (or Curves) adjustment, change the channel selection from "Master" to "Alpha." You can then apply the Levels or Curves to the Mask directly.
 

Today, let’s have fun with Gradient Maps…
Gradient Maps are a great way to color grade photos, since they map dark, light, and midtone values according to a pre-defined gradient. This can easily define a “look” for photos that might otherwise be hard to accomplish.
Although I am not a user of Photoshop, our “arch rival” has a wonderful group of gradient maps called “Photographic Toning” that are specifically designed to color grade photos. Although you have to drill down through a few panels and dialog boxes to find them (and you sort of have to know they’re there in the first place) they are a truly nice addition. Also, they are easily obtained by anyone.
But, as they say, there’s the rub. Affinity Photo cannot import Photoshop gradient maps. Affinity Photo can store pre-defined gradients in the Swatches studio, but for some unknown reason the stored gradients are not available from the Gradient Map studio panel. Gradient Maps can be stored as presets, and can be chosen from the Adjustments panel, but I don’t believe they can be easily exported from one computer and brought into a different one.
So… after a long couple of days of transcription, I have created a set of Macros that apply each of the 38 Photographic Toning gradient maps. Since macros are easy to store, and to share, I am making them available for anyone who wants them.
There are actually 2 sets of Macros included - each as an easy-to-import Category from the Library panel. The first group of Macros is called “Photographic Toning Gradients” and these are named according to the gradient map they apply. Each macro creates a Gradient Map layer, applies the appropriate color values, and names the layer according to the gradient map it applied. The second set of macros is called “Photographic Toning Gradients - reduced.” This category also applies the gradient maps in a similar fashion, but then reduces the opacity of the layer to 30%. This reduces the effect of the Gradient Map, and produces a much subtler effect.
Here is an image that shows the full-strength versions of all 38 gradient maps.

And here is a photo to which I’ve applied a full-strength gradient map, and also a reduced-strength gradient map.

These macro categories are included in the ZIP file attached to this post, along with a Letter sized JPG that includes samples of the gradient maps. Also included in the ZIP file is another macro category that includes one more macro. It’s called “Obama Hope Poster” and, as you might have guessed, it turns any photo into an Obama Hope-style poster. Just because…
Please enjoy them!
Photographic Toning Gradient Maps.zip

Puffin...
 
You can't open an .afmacros file by double-clicking on it (or, I presume, by choosing Open... from within Affinity Photo). Rather, go to the Library panel, click on the "hamburger" menu on the top (the VERY top, not the menu that exists in each Category) and choose Import Macros... Open the file from the dialog box, and Affinity should import the macros into a new category in the Library panel.

Starting with a base portrait, add 1 or more pixel layers above it. Paint on those pixel layers with the desired color, and set the Blend Mode for the extra layers to "Color." This changes the color of the pixels, but keeps their luminosity intact from the layer(s) below. In the example below, I've started with a portrait (from Pixabay) and added two layers - one orange and one red. Obviously, doing a bit more tinkering (feathering the edges, desaturating the colors a bit, and so forth) would enhance the result. But what you are looking for is quite possible.