Okay, I am not expert on HDR photography, but this is the best way I can describe it:
You take a picture at normal exposure. Then you take the same picture over-exposed, and again, under-exposed. You can take more than three actually. You can take many pictures at varying exposures. (I believe my Photoshop HDR function takes up to 11.)
Then I used Photoshop HDR Merge to combine the images and it gives you extra detail that you might not be able to capture with just one level of exposure.
Like I said, I'm no expert. That was a pretty rudimentary explanation. So I'll show you some pictures along with it.
First, I want to say that there aren't a lot of bridges around here. Certainly none that I can think of with beautiful city scapes underneath them. (Oh to be back home by the Narrows.) So I was limited in that respect. But the challenge was simply the view from under the bridge and that was doable.
Here are the ones I took. (It snowed the evening before so there was a light dusting on everything.)
Let's take this last one for an example. Here is the original photo.
Now over exposed.
And under exposed.
When combined, they give you this image below. (Interesting to note that in the original, it is still too bright to see the detail in the snowscape beyond the bridge. Without the underexposed photo, you would not be able to see the detail in the trees.)
It is an interesting effect that I would like to play with some more. In fact, I'm kicking myself that I didn't know what to do earlier in the week when we had an amazing sunset. Here is what we saw - no edits.
I tried to cheat. I took the picture and over exposed it in photoshop and under exposed it saving each copy. Then I combined the three. (So not original pictures, but the same basic idea.) It went a little psychedelic on me.
I will definitely be trying this again next time the sky gives me pink and yellow stripes.
Next week: Portraits - Simple Natural Light