Luminosity masks in Affinity Photo

[Earlio]

In Affinity Photo 1.7, you can create a Luminosity Mask with the following key combinations:

Mac:  <Option-Command> Left Click Thumbnail of the pixel layer required.

PC: <Control-Alt> Left Click Thumbnail of the pixel layer required.

The Blend If function works well.  

There is also a method to create a Macro which selects each tone profile (Midtones, Highlights, Shadows) and you can then change each of the parameters to your liking and this gives a great deal of tonal control, the keystroke method for a Luminosity Mask is a "quick and dirty" way to get a quite a nice result.

I have attached the Macro should you prefer this method, or have a trickier image to edit (for Mac - I don't know if this can be directly imported into a Windows environment -  If required for PC users, I can set out the steps needed to create these Macros).

Luminosity Masks (Tones).afmacros

[endrus]

I have created a "Photoshop-style" channel-based luminosity masking macro following the instructions provided in previous comments. Credit goes to Depa and smadell.

Macro is created and tested in Affinity Photo 1.7.3 running macOS Mojave

This is not to support any debate which luma masking is better or worst just for technical curiosity. I have discovered a shortcomming in Affinity Photo 1.7.3 as the channels can not be named for the macro. If the macro is not recording they can be named properly. So mind the order of the channels such as: Highlights 1-6, Shadows 1-6, Midtones 1-6 from top to bottom.

Use of the macro:

1. Open your image.
2. Import the macro. View / Studio / Marco / Import
3. Run the macro and / or save it wherever you wish
4. Open the channels panel (View / Studio / Channels)
5. There you have all the 18 masks in the lower part of the channels panel
6. Pick the preferred luma mask from the channels panel and right click 'load to pixel selection'
7. Layer / New Maks Layer
8. There you have the chosen luma mask loaded to your masked layer
9. Proceed with your edits as you wish

Do you really need 3x6 channels? Probably not, but if in any case you find use for it, there it is.

Usually 2-3 luma masks are used per image depending on the luminosity info of the photo and the complexity of the edit.

Jimmy McIntre is a master of all luma magic worth checking out some of his tutorials on masking, blending, orton effect etc

 

6-level H-S-M Luminosity Masking : Spare Channels.afmacro

[Ma3rk]

I'll give this a try very soon.

I'm just a bit stunned that luma mattes are such issue in AP. Seems like a very basic function. It was that way in Photoshop as too really which is why I used to do this sort of work in After Effects.

Have what you want to use as a matte above your target layer, alpha or gray scale, & it's a couple clicks & your done by selecting one of 4 options for alpha or luma.

 

[OliverSpain]

It is in spanish language. Can it help you? I created 3 channels for hightlights, 3 for shadows and 3 for midletones.

https://youtu.be/y1mRb0P1LHY

 

The steps are those indicated by Smadell:

 

Duplicate background 2 times.
Name the 1st duplicate “Light Temp”
Name the 2nd duplicate “Dark Temp”
With “Dark temp” layer selected, choose Layer > Invert

Select layer “Light Temp”

In Layers panel, Command-Shift-Click on layer icon to create luminosity selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel.
Rename this channel Lights 1
Deselect the selection.

In Channels panel, right click on Lights 1 and choose Load to Light Temp alpha
In Layers panel, Command-Shift-Click on layer icon to create luminosity selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel.
Rename this channel Lights 2
Deselect the selection.

In Channels panel, right click on Lights 2 and choose Load to Light Temp alpha
In Layers panel, Command-Shift-Click on layer icon to create luminosity selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel.
Rename this channel Lights 3
Deselect the selection.

Delete layer “Light Temp”

Select layer “Dark Temp” [remember - this is the inverted version of the background layer]

In Layers panel, Command-Shift-Click on layer icon to create luminosity selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel.
Rename this channel Darks 1
Deselect the selection.

In Channels panel, right click on Darks 1 and choose Load to Dark Temp alpha
In Layers panel, Command-Shift-Click on layer icon to create luminosity selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel.
Rename this channel Darks 2
Deselect the selection.

In Channels panel, right click on Darks 2 and choose Load to Dark Temp alpha
In Layers panel, Command-Shift-Click on layer icon to create luminosity selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel.
Rename this channel Darks 3
Deselect the selection.

Delete layer “Dark Temp”

In Channels panel, right click on Lights 1 and choose Load to Pixel Selection
In Channels panel, right click on Darks 1 and choose Intersect with Pixel Selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel
Rename this channel Midtones 1
Deselect the selection.

In Channels panel, right click on Lights 2 and choose Load to Pixel Selection
In Channels panel, right click on Darks 2 and choose Intersect with Pixel Selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel
Rename this channel Midtones 2
Deselect the selection.

In Channels panel, right click on Lights 3 and choose Load to Pixel Selection
In Channels panel, right click on Darks 3 and choose Intersect with Pixel Selection
In Channels panel, right click on Pixel Selection and choose Create Spare Channel
Rename this channel Midtones 3
Deselect the selection.