Saturday, November 21, 2009

Trying HDR photography and saying good-bye for the year to a Great Blue Heron


I have been experimenting with HDR (High Dynamic Range) imaging. It's a technique of fusing several images taken with different exposure, i.e. over-, under- and correct exposure, resulting in an image which contains a wider range of very dark and very bright areas than would ordinarily be possible. Since there is always a small delay between each exposure the images are best taken with the camera on a tripod. Handheld images, like mine,  usually result in some ghosting and are never quite sharp.

Here is my first effort, a view from our deck on the wetland next to our house. I used a demo version of Photomatix. The sky often comes out gray and has to be corrected in Photoshop. In fact most images require further editing in Photoshop:

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Here is a landscape taken in late afternoon sunlight:


After


Before

A mall in Keene:



The technique is derived from 3-D imaging in video games and many of the images on the net are still reminiscent of a toy-size model set-ups. One give-away of an HDR image is the appearance of a sky with unusually dramatic cloud formations. Here is a site that explains the technique and has some good examples along with  tutorials: Stuck in Customs. I am not sure how far I am going to go with this. I generally prefer more natural-looking images but it might be fun in the winter when there are not many birds around.

While walking on the railroad trail behind the shopping mall in Keene a Great Blue Heron suddenly appeared overhead. It was the same one I had been observing for much of the summer and fall, first as a juvenile and now as a grown bird. He'll soon be off going south.



Good Birding! And Happy Thanksgiving. For us it's off to Michigan again for a week to visit family..

4 comments:

  1. How odd! I was just discussing HDR today with a Flickr friend. I don't really get it, but I thought it sounded like fun - especially during the winter. I have quite a few shots of cardinals and sparrows and juncos already!

    Why do you say the GBH is leaving? They don't all leave during the winter; I've seen them around here, anyway. If I lose my Great Blues on top of everything else, it will surely finish me off!

    Please - say it aint so!

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  2. Susan, HDR does not work for moving subjects such as birds unless you go through a complicated masking process in Photoshop where you retain only one exposure of the moving subject in the final image. So landscapes work best.

    In our area - Windham County, Southern Vermont - GBHs don't stay around when the ponds and wetland are frozen solid, as is usual in Jan and Feb. I looked it up on the map data on eBird. It's interesting to scroll down and look at what birds are present during the deep winter month. In MA GBHs seem to stay all winter. I am very much aware of the temp change when driving on I91: as soon as I cross over into VT, when mountains appear on the sides of the road, there is snow on the ground.

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  3. Goodness, what a yard you have!!!!!

    Seems like a 200 species kind of yard....

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  4. Laurent, not really. Our dogs create too much of a ruckus...

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