HaveCameraWillTravel
Dec-25-2010, 04:59 AM
Hello, and it's the time of year to take advantage of all the holiday lighting that will soon be put away for next year. HDR is a great tool for capturing the colors of holiday lighting. If you've tried taking a picture of a lit Christmas tree, you soon find out what a large dynamic range is required to reproduce both the color in the bright centers of the bulbs, AND the detail in the darker tree needles and background. One picture can't do both, but HDR comes to the rescue here. But HDR software is just like any other: GIGO (garbage in, garbage out.) To get a good series of nighttime images for your HDR software, here are some tips, followed by two shots for illustration:
1) Use a tripod, shut off image stabilization, use remote or cable shutter release. At the least, use a self-timer.
2) Manually focus on the subject, or initially auto-focus, then switch to manual to lock the focus in place.
3) Shoot RAW for more detail and less noise.
(If you can only shoot JPEG, set white balance around 3600K. "Tungsten" or "Incandescent" tends to give a cold
cast to the lights)
4) Turn off sharpening and set saturation to normal. Set long-exposure noise reduction on if you have it.
5) Shoot at the lowest ISO possible (usually 100, some cameras go down to 50)
6) Set aperture priority (or keep the aperture constant), change the only shutter speed.
7) Take your exposures one stop apart. If you find out you only need them two-stops apart you can just load every
other shot. Better to have and not need...
8) Don't shoot if it's windy, or if the subject(s) is(are) moving. You'll end up with ghosting, unless that's your intent.
9) Set the shutter on the first image to overexpose so much that the darkest areas are at least in the midtones.
10) Keep increasing shutter speed and shoot until the last picture is so underexposed that there are no blown highlights anywhere (usually in the centers of the bulbs.)
As I mentioned in another thread, I had an issue with Photomatix, that it was producing black spot artefacts on my Christmas lights shot. A fellow member gave me that critical last tip - make sure NOTHING is overexposed in the final exposure for the HDR set. The pictures below are both final tonemapped output from Photomatix, cropped down to show the artefacts easily. They do differ in contrast and detail, because they were processed with different settings. As they are certainly "nothing to write home about", they are just here for illustration:
HDR output when the most underexposed image I loaded in had blown highlights.
http://gonyeagalleries.smugmug.com/Illustration/Technique/1138272211_B7WtL-L.jpg
Now, when I included the last underexposed image which had no blown highlights.
http://gonyeagalleries.smugmug.com/Illustration/Technique/1138272250_jfQ3A-L.jpg
Hope this information is helpful. Happy shooting!
Art
1) Use a tripod, shut off image stabilization, use remote or cable shutter release. At the least, use a self-timer.
2) Manually focus on the subject, or initially auto-focus, then switch to manual to lock the focus in place.
3) Shoot RAW for more detail and less noise.
(If you can only shoot JPEG, set white balance around 3600K. "Tungsten" or "Incandescent" tends to give a cold
cast to the lights)
4) Turn off sharpening and set saturation to normal. Set long-exposure noise reduction on if you have it.
5) Shoot at the lowest ISO possible (usually 100, some cameras go down to 50)
6) Set aperture priority (or keep the aperture constant), change the only shutter speed.
7) Take your exposures one stop apart. If you find out you only need them two-stops apart you can just load every
other shot. Better to have and not need...
8) Don't shoot if it's windy, or if the subject(s) is(are) moving. You'll end up with ghosting, unless that's your intent.
9) Set the shutter on the first image to overexpose so much that the darkest areas are at least in the midtones.
10) Keep increasing shutter speed and shoot until the last picture is so underexposed that there are no blown highlights anywhere (usually in the centers of the bulbs.)
As I mentioned in another thread, I had an issue with Photomatix, that it was producing black spot artefacts on my Christmas lights shot. A fellow member gave me that critical last tip - make sure NOTHING is overexposed in the final exposure for the HDR set. The pictures below are both final tonemapped output from Photomatix, cropped down to show the artefacts easily. They do differ in contrast and detail, because they were processed with different settings. As they are certainly "nothing to write home about", they are just here for illustration:
HDR output when the most underexposed image I loaded in had blown highlights.
http://gonyeagalleries.smugmug.com/Illustration/Technique/1138272211_B7WtL-L.jpg
Now, when I included the last underexposed image which had no blown highlights.
http://gonyeagalleries.smugmug.com/Illustration/Technique/1138272250_jfQ3A-L.jpg
Hope this information is helpful. Happy shooting!
Art