This is a really good way to produce a Luminosity mask in Photoshop Using Channels and no need to use Filters or a purchase a plugin. It is best served by being applied as a last step in your workflow and on any images that appear slightly ‘flat’. It will bring out your shadows and brighten your highlights and give the image a bit of SNAP ! 😀
So here is one of my interior HDR images I have Finished working on with Filters and adjustments and I wanted to add a little bit of POP before I Finalise it. It was a 5 bracket HDR, shot with a Nikon D800 + Nikkor 14-24mm 2.8 inside St Stephens Chapel, Brisbane, Australia. With this HDR I wanted to keep the post-processing on the ‘realism’ side so most of the adjustments were to do with colour and brightness.
Down the right side you can see I have combined all my layers into 1 layer, seen highlighted in blue. This method for a Luminosity mask can be applied to a single layer though even when you have multiple layers.
So to begin with it is easier for later if you are using the Marquee (M) tool which is on the left hand side in your tool bar, in Photoshop CS6 it is the 2nd from the top.
Now go down to where the blue highlighted area is on the above image and left click on the channels tab, next to layers. If it isn’t Visible go up to the top menu bar and select > Windows > Channels and it will now pop up.
Next you want to hold down ‘CTRL’ and left click the layer line RGB, which is the top one. You should see the marching ants come up on your image noting that you have made a selection. You can see my marching ants in the image below.
Left click on the layers tab, next to channels.
Next you want to move your mouse onto your actual image and right click it, and a list will come up. Left click on ‘Select Inverse‘ and you will notice that your marching ants have chosen new selections. This is the selections you want !
Now you are ready to make your adjustments, so you go up to and left click brightness/contrast which is located above your layers panel here >
You will notice when you select it, that it will make a new layer and this is going to be your Luminosity mask layer and you can see the difference it is making by left clicking the eye on and off next to the text on the very far left on the layer. At this point you will notice your marching ants disappear but this does NOT mean that you haven’t still got the areas selected, the ants just aren’t visible anymore.
It will also pop up your panel for making your adjustments and you can adjust your brightness and contrast on only your selected areas in your image. You will be able to give POP to your highlights and shadows without making changes to the areas in the image which are exposed in a correct manner. You will instantly notice how much better your image looks when you start moving the sliders.
Usually you will want to increase the brightness whilst dropping down the contrast a little, BUT every image is different so play around with the 2 sliders and find the combination which works BEST for your particular image. Once you are happy with it, you can save your image and you are done. If you want to combine your mask to your layer and continue working, just highlight them both in your layers panel by clicking the brightness/contrast layer holding down SHIFT and clicking on your image layer to select them both. Then hit CTRL + E to combine them into one layer. You can combine any number of layers in your layers panel, into 1 layer… e.g. 2,3,4, etc. This is is how you combine mask layers and keep working. I will write a tutorial on masks soon.
So here is my image after I have applied my Luminosity Mask and it just added that little extra something that it was missing ! The chisel marks in the stone wall are more prominent and the sculpture isn’t as grey in tone and has a greater tonal range in general.
And that’s it, you’ve now added a Luminosity Mask to your image and made it A LOT less bland.