I originally took this as a candidate for Assignment 3, ultimately rejecting it because the figures in the frame were too dark. This is a difficult subject to select for lightening as there are very distinct differences in both colour and brightness on the two figures. I also wanted to maintain the dark shadow at the back of the photo, so could not use a broad levels adjustment to add some fill light to the people.
I turned to Photoshop CS4, can't afford the upgrade at the moment, and started playing with the selection tools. My first ploy was to use the Magic Wand Tool, but I kept getting bleed into the background or too little selection. I then used the Quick Selection Tool in both add and subtract modes to build a basic selection around the two figures. At this point I was puzzled how to refine further, but learned that I could further refine the selection in Quick Mask Mode. I did this using a variety of different brushes and pencil tools to add to the mask and the eraser tool to eliminate any mistakes.
A further step I took was to save the final selection as an Alpha layer, so that I could retrieve it as needed. The eventual mask looked like this:
The final step was to apply a curves adjustment to the selection and I eventually finished with an image containing two very much brighter people:
They now look as if they are walking in the sun rather than the shade, so a big improvement to the image. This was a complex technical challenge and a useful skill, although I still think this is an emergency recovery rather than a technique I would choose to deploy purposefully.