Luminosity masking is a method of creating a selection and applying it to a channel mask based upon how bright an area is in a photo. Utilizing it to blend multiple exposures instead of using an HDR program allows a more realistic end result photograph, without halos typically associated with HDR.
In order to keep it simple, shoot the exposures 1 stop apart, and shoot enough to cover all of the range of the light.
After you have your exposures, you can then use existing tools, or you can make actions to create channel masks. My suggestion is to buy a tool panel that helps you do it quickly and easily. My two top choices are Raya Pro and Lumenzia.
Raya Pro is what I currently use, and it is extremely powerful; however, you need to have a computer that has a good bit of memory, as it creates all of the channel masks with a single click, which makes the file size quite large. Memory and hard drive space is cheap though, so this is the route that I went with.
I do not have the Lumenzia panel, but after watching the videos, it was obvious that it is an excellent panel and one that has some strengths. Particularly, this panel does not use channel masks, and keeps the file size very small. This is important if you are using limited processor power or memory. If you are on a laptop or an older computer, this is probably the best panel for your needs.
If you insist on using actions, ShutterEvolve has a free download of actions that will create the masks. I used these for months, but finally decided to buy his Raya Pro panel, and I definitely do not regret getting the panel.
Just to show you how powerful, yet easy it is to do luminosity masking with the right tools, the below photo is one that I did from only 2 exposures, in less than 3 mins, with no hand edits – and it’s the first photo that I ever did with Raya Pro. Never having touched the tool before, and without watching his tutorials, I quickly realized what I needed to do to blend the photos. I’m sure that I could improve it with a few more minutes, but this is an example of what anyone can do in just a few minutes.