one area where affinity photo struggles to compete with photoshop is luminosity masking a few years
ago i released this video explaining how to create luminosity masks in affinity photo just as you
might in photoshop the only problem with that approach is that the processing is complicated
you see photoshop users have an advantage when it comes to luminosity masking
they can use third-party extensions that make the process much easier and unfortunately these
don't yet work in affinity photo that's why i've been thinking hard and i've come up with a simple
method to produce luminosity mass in affinity not only that but this new method also allows you to
create luminosity masks interactively let's look at how using this landscape image the first thing
i need to do is produce a black and white version of the image to work with i'll just add a black
and white adjustment layer using the icon at the bottom of the layer studio panel the next step is
to add three curves adjustment layers again using the icon at the bottom of the layer studio panel
then i'll rename these new curve layers to be lights darks and mid-tones we'll be using these
to create our luminosity masks finally i'll just group all four layers together and call
these luminosity masks having the layers in a single group like this keeps them separate from
our other adjustments now for the clever part which is to use our curves layers to create
the luminosity masks we'll start with the lights curve first which we'll use to target the lighter
tones of the image the first point i'm going to add to the curve is in the center i'll then drag
that down so that it's on the lower line of the grid the second point i want to add is where the
curve crosses the upper grid line i can then drag that point up until it meets the diagonal red line
notice that the black and white image is now very dark except for the lightest areas of the image
we can therefore use this to create a mask targeting the lightest areas
let's turn that off now so that i can show you how to adjust the darks curve
this time we want to make the darkest areas of the image appear white and the lightest areas
appear black the way to do this with a curve is to reverse the direction of the curve line
by moving the black point to the top left of the grid and the white point to the bottom right it
produces a negative of our image now i can repeat what i did for the light curve i'll click on the
center point and drag that down to meet the lower grid line then i'll add another point where the
curve crosses the upper grid line before dragging that up now we have an image that we could use to
create a mask targeting the darkest areas let's turn that off and adjust our third curve to target
the mid-tones of the image first i'll move the white point of the curve down to the bottom so
that the image appears black now i can add a point in the center of the curve line and drag that up
to the top then i'll add a point on the left side of the curve and drag it in towards the center
after that i'll repeat the process on the right side of the curve now we've created everything
we need to produce luminosity mass to target different tones in the image now let me show
you an example of how we can use these curves and then i'll show you some ways to refine the
selection process let's start with an adjustment to lighten the shadows in this image i'm going to
do this by adding a new empty layer and changing the blending mode to overlay what this means is
that when i paint onto the layer using white paint it will lighten those areas of the image
of course what i don't want to do is paint on the lightest areas to make those lighter still which
is where the darks luminosity mask comes in to use it i need to make only the dark curve visible
now if we look at the channels window we can see a composite red green and blue channel when i right
click on one of these channels i can convert it to a selection by choosing the load to pixel
selection option now you can see the marching ants indicating there's an active selection at this
point you can hide the luminosity mask group in the layer studio panel the next step is best done
without the marching ants being visible so i'll hide them using the show option in the view menu
now i can paint using white onto my layer in the areas where i want to lighten the shadows
a tip when you're doing this though is to have the layer opacity set at about 70 percent this
allows you to increase or reduce the strength of the effect using the opacity slider the image is
now looking much better but it's left it looking a little flat because there isn't a true black let's
fix this by adding a levels adjustment layer notice that the new adjustment is created with
a layer mask produced from our active selection now i can adjust the image whilst only affecting
the darkest areas let's clear the dark selection now by pressing command and d on your keyboard if
you're using a windows pc that's ctrl and d we'll now go back to our luminosity mask group and this
time we'll load a light mask to work with the process is the same as before where i make only
the lights curve visible i can then right click on one of the composite channels and choose the look
to pixel selection option this time we don't see the marching ants because if you remember
i chose to hide them in the view menu let's then hide the luminosity mask group so we can work
on the image if i add a levels adjustment layer again it creates a mask from the active selection
having done that i can adjust the highlights in the image using the levels adjustment sliders
so far we've used our luminosity mask created from our curves without changing them
but we can also manipulate these curves to better target specific parts of an image like
these ferns before i do that i'll clear the active selection by pressing command and d on my keyboard
let's make the luminosity mask group visible again so we can see the effect of the curves
if i check each of the curves in turn we can see that the midtone curve highlights the ferns best
out of the three in this example you can see the ferns are very wide so we probably don't need to
make any further changes but if we didn't need to better target an adjustment you would just
open the curves dialog and adjust it by moving these points in towards the center the selection
targets a narrower range of mid tones when you have the mask looking the way you want it right
click on the composite channel and load it we can then hide the luminosity mask group while we work
this time rather than simply lightening the ferns i'm also going to apply some colour
to do this i'll sample the orange in the sky so that i can paint with it using the paintbrush tool
then on my new layer i'll reduce the opacity to around 70 and this time i'll
set the blending mode to soft light now using the paintbrush tool i can paint over the ferns
this not only lightens the ferns but it warms them by adding the orange ice sample from the sky
i can also paint over the clouds in the sky which will help bring out any orange there
as well now earlier i said that we could adjust our mass to target different areas of the image
and we've already looked at one way of doing this another way to refine the luminosity mask
that you might want to try is to adjust the controls of the black and white layer by using
the colour slider you can change what you target in the image the only thing to be careful of is
creating too sharp a transition between the light and dark areas in the mask when you don't have a
gradual transition through grey the luminosity mask won't produce a natural looking result
another way to refine your mask is to combine them with the blend ranges control this video explains
how that works and is a good one to watch next you can even use blend ranges as an alternative
to luminosity mass i hope you found this video helpful and i'd really appreciate it if you share
it with other affinity photo users don't forget to subscribe and i'll see you soon in another video