Monday, September 29, 2008

my take/comments on hdr photography ...

... so recently, well, more than recently, people always ask what's up with my photography.

"it's hdr" i respond.
"i don't know what that is" i usually get back
"dot dutta wonka wonka dot dutta bakka lakka dot dutta blah blah" the story goes.

... so i am deciding to just blog about it, without pictures (the irony) to give all you readers an overview, express my own personal opinions on the subject matter and maybe, just maybe insight some knowledge without having to repeat myself ;)

to boil it down, hdr photography is just a simple technique that you can employ in the post-processing of your photography. you take (3) or sometimes (5) or (7) of the exact same image, over- and under- exposed, then in the post processing of those images, combining to show the true dynamic range of colors and intensities available.

i.e. take one perfectly exposed shot, one over exposed, one under exposed, combine the three and you get the brightest of the bright, darkest of the dark and an insanely colorful, sometimes cartoon-y picture that makes you warm and fuzzy inside (ok, sometimes). read wiki on hdr photography for more techno-history-garble

why take hdr photos? why not? it's your own personal preference, i just absolutely love the range of colors, shadows, and highlights that are produced from the processing.

here's my take on things. it's not that simple. you need to have a lot of patience and control. it's not that simple. did I mention, it's not that simple?

once you get the hang of things, it is, but it does take a lot more work than just a plain simple image and some photoshop post-processing. one can argue that it takes the same amount of time.

here's what i usually do when i take hdr photos:

  • mount camera to a good solid tripod (this is key, i mean seriously!)
  • frame a shot
  • check your iso, shutter, aperture settings
  • take the shot again, modify shutter and/or iso settings
  • repeat the above a few times, until you get a shot you actually think is almost perfectly exposed.
  • the above two steps usually takes me 6-7 frames
  • set your auto-exposure bracketing settings on your camera, i usually do (3) frames, +/- 1/3ev up and down, or sometimes +/- 2/3ev
  • do not move your camera do not shake your camera do not move your camera ... get a remote trigger release
  • take your (3) shots
  • turn off your bracketing
  • take a picture of the ground, your hand, something or anything to segregate the set you just took from the next set you're about to take

after this, I sometime tweak the iso or shutter a bit, and then re-shoot the hdr frames again. as you can see, it takes sometimes up to 10-frames to get a 3-shot hdr setup. is it worth it? you can make your own judgment as you try it yourself, it's not for everyone.

what if your camera doesn't have auto-exposure bracketing (aeb) settings/controls? get one that does. ok seriously ... try not to move your camera. learn the menus and how to configure aeb or change your exposure settings quickly and efficiently so you induce as little camera shake as possible. to get the most crisp, precise images possible, do not move the camera. another option is look into tethering your camera to your laptop and control your camera settings and snapping from the laptop. bibble labs makes great software for this for the major camera brands.

did i mention not moving your camera? yeah, don't do it. don't touch it, don't shake it, don't press the buttons, do not move it. this gets more and more important as the light gets less and less and the shutter times increase. you'll just get a bit of a mess. the concept of hdr is combining three identical images at different exposures. if you move or shake your camera even in the slightest, it'll show in the final hdr images. things will not line up, or simply you'll just get a lot of ghosting in the picture. sometimes, it's a neat result, say for example grass or water, because it adds the sense of rushing movement, but for most things, not so good. i got myself a phottix n8 remote trigger, it was cheap ($35) from ebay (they only sell on ebay) but it's got great reviews and i've had a lot of luck with it. no camera shake. that's the key.

so now that i've taken the pictures now what? well. the first 6-7 frames i've shot to test out settings, i look at see how i could have taken them better, see what works, what doesn't. the (3) frames that are set to be combined, i put them on my mac and into photomatix raw (no processing what so ever). photomatix combines the images and then i tweak the saturation levels a bit and output my hdr file. i've tried abobe photoshop cs2 with mixed results, photomatix always produces great mappings with my raw images. i rarely, and i do mean rarely ever have to process any of my hdr images after this and i am usually happy with the results

so long story short, i love shooting hdr. it's a bit of a challenge, but it's a lot of fun to see the results. i also find that hdr works best in low-light situations or shots that have a lot of contrast between shadow and light. then again, i enjoy the hdr's of random things sitting on my desk. i personally think it gives some pictures a lot more depth although some argue that the same result can be had with filters. you can make your own conclusions.

hdr won't make you take better pictures though. i still believe you need to be proficient at taking one good, properly framed and exposed picture. hdr is just setting your camera to take two more. you still need to practice and understand the basic principles of photography, otherwise you're going to be shooting a lot of throw-away shots because you'll just be tripling your badness.

1 comment:

Anonymous said...

This is such a great article! Thanks so much for sharing your thoughts on HDR and for the lesson as well. I'll definitely have to try it!