In my opinion, one of the main reasons (if not the main reason) to use Photoshop is the option to make and use masks, which allow a correction or adjustment to be applied to one specific area of an image. But actually selecting that specific area can be extremely difficult, especially if there are fine, overlapping details, Trying to use the standard selection tools such as the lasso or magic wand is far too often a lesson in frustration. Selecting by luminosity, by tonality (how light or how dark a given area), is a much better way as this luminosity selection is based on the image itself and consequently will make a self-feathering selection.
Quite a few years ago I learned about making luminosity selections from Tony Kuyper’s website, www.goodlight.us. In fact, I wrote about luminosity selections, and Tony’s Photoshop actions to make these selections, in some of my early eBooks on Photoshop. Over the years Tony has refined his actions, and recently he produced a completely new Photoshop “Action Panel version 3.” I’ve used his previous actions, but his latest panel is amazing.
Do yourself a big favor: if you’re running Photoshop CS5, CS6, or CC, particularly if you’re a landscape photographer, get the new action panel. Do yourself an even bigger favor, and get the action panel along with Sean Bagshaw’s video tutorials on using these actions. The total package is $79 and is worth far more than that. I highly recommend both the action panel, and the video tutorials.
Here’s the link about the panel: http://www.goodlight.us/writing/actionspanelv3/panelv3.html.
And the purchase link (see the “special offer” at the bottom of the page): http://www.goodlight.us/specialoffer.html.