For the photogeeks out there… HDR

As some may know I did a ton of photography in high school (yes, I did in fact letter on the Yearbook Team), even a bit in college and I love to fiddle with photography when I can find the time. So, about a month ago I came across an emerging digital photography technique called High Dynamic Range, or HDR photography, that peaked my interest.  Although the science behind the technique is significant it boils down to a method in which you can use either multiple exposures or a RAW image from the proper camera to create photos that have previously been impossible. This is done by taking at least 3 different exposures of the same subject, at -2, 0, and +2 stops (this can either come from autoexposure braketing or generated from a single RAW file) and then using an application that combines the range of all the photographs into a single image that produces amazing detail in highlights and shadows.

 Here’s the short series of steps that I took to create my first HDR photgraph (I followed the tutorial found @ http://www.vanilladays.com/hdr-guide/ ):

1. I used my Nikon D70 to take some RAW format images at a birthday party this weekend.
2. In Photoshop (CS3 Beta) I loaded the RAW image and created 3 .tif files: one at -2 exposure, one at the original exposure and a third at +2 exposure. Here’s the normal exposure / original image:
   

   

3. I downloaded Photomatix Pro from Photomatix.com
4. In Photomatix I opened all 3 exposure photos
5. Then I used HDR->Generate, selected the 3 open photos and it created the HDR image for me.
6. From here Photomatix gives you a bunch of options to control color saturation, luminosity, etc. but for the purposes of this demonstration I left those settings to default.
7. Finally I saved the image as an 8-bit .tif and used Photoshop to create the final image in JPEG format:
   

   

   So, a few notes on my adventure:

•  In comparing the 2 photos I’m very happy with the result. The HDR process generated a much more vibrant photograph with exceptional detail. The photographs I took didn’t have dramatic swings in exposure that you see in some of the more shocking HDR examples, but I do think it made this photograph better. I’m betting that doing some skillful Photoshop work could have produced a photo near this quality in color saturation, brightness and tone, but this version was piss-easy to create and I’m willing to believe it’s better, simply because I can call it an HDR image.
• From what I’ve read and seen online the process works much better if you use the Autoexposure Bracketing (AEB) to take 3 distinct images rather than using the RAW format. However, it should be noted that should you want to create an HDR image of anything that moves (like people, animals or anything else that isn’t an architectural or lanscape shot) RAW is really your only option. You can’t use AEB on moving objects and get the benefit of HDR assembly.
• Photomatix costs $99 for the licensed version that won’t add those clever watermarks you see on my photograph.
• Adobe Photoshop CS3 does have an HDR merge utility, which I tried, but it’s really clever and it knew that all 3 of my images came from a single RAW file and told me to bugger off because of this. Looks like I’ll have to revisit that option with some good AEB shots.

In all I like this new HDR thing. Given the time investment and file size of RAW photos I probablywon’t HDR another kid’s birthday party, but I am motivated to go out and get some good landscape / architectural photgraphs that could really leverage HDR and see what the process produces. For further research and some amazing HDR photgraphs, goto: http://tutorialblog.org/hdr-tutorials-roundup .