It is easy for digital photographers to get lazy out in the field — “Oh, I can fix it digitally, later. . . .”
There is nothing necessarily wrong with that approach, but I like to try to get it right in the field, preferably all in one shot. And sometimes that takes a few tricks.
Take the image below I just photographed.
A long exposure can give a nice abstract feel to an image. Using a polarizer slows down your shutter speed about 2 stops helps give you that longer exposure. Combined with a small aperture and low ISO, I had a nice long 30 second exposure to really abstract the water on the lake.
But what about the sky? It is a lot brighter than the darker foreground here and will overexpose. I could shoot it in two different exposures and add in the properly exposed sky later, but I’d rather get it one shot.
So I pulled my 3 stop Graduated Neutral Density filter out of my bag and held it over the lens to bring down the light in the bright sky and equalize the exposure. Voila – you get the image all in one shot. A little more work up front, sure, but worth it to me. (And less work on the computer, later!).