Search

December 17, 2007

What is HDR Photography

Click to view larger image of an HDR photo taken at nightYou might have noticed that I describe some of my photos as being "HDR". You might be wondering just what is HDR photography, so here's an explanation for you.

HDR stands for High Dynamic Range. HDR photography consists of blending multiple exposures of the same subject at the same aperture setting but with different exposure lengths. Shooting the same subject in this manner is known as "bracketing" and most SLR digital cameras will have a bracketing setting. My Canon EOS 20D for example, allows you to shoot 3 images in a bracket. Under the menu option you specify the exposure intervals and then you also need to set the camera to shoot multiple exposures. When you hold down the shutter release, the camera will take the 3 different exposures for you. The result is that you end up with photos that are under-exposed, correctly-exposed, and over-exposed.

In the blending of the multiple images into the one photo, the over-exposed image is accentuated for the shadows, and the under-exposed is accentuated for the highlights. The correctly-exposed image is used for the mid-tones.

There is software available to assist with the blending, starting with Photoshop and other programs available online. I also have purchased Dynamic Photo HDR from mediachance.com, and Photomatix Pro available from hdrsoft.com. Photomatix has a free version, but when you save the file it puts Photomatix all over the face of the photo, so if you're going to get serious about this stuff, you'll need to hand over some money.

Here's a link to some of my HDR photos.

No comments:

Featured Post

Industrious Rat on Wildlife Camera

Something a little different today - an infrared video compilation of a rat the insists on covering my deck each night with sticks and leave...

Most-Popular Posts in the Last 7 Days