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email thisI've been exploring the D70's bracketing feature. Bracketing means taking an extra photo above and below a given setting, typically varying the exposure. According to this tutorial:
The reason you do this is because the camera might have been 'deceived' by the light (too much or too little) available and your main subject may be over- or under-exposed. By taking these three shots, you are making sure that if this were ever the case, then you would have properly compensated for it.
With the D70 you have four bracketing choices: AE (exposure) & Flash, AE only, Flash only, or White Balance. You can also choose the order in which it performs bracketing. Both of these settings are accessed through the CSM menu.
To initiate bracketing the camera has to be in one of the four programmed modes (P, S, A, and M). Holding down the BKT button highlights bracketing options in the control panel, the back wheel toggling bracketing on/off, the front wheel dials through the various number of steps and step amount.
The bracketing icon indicates how many steps are left and which "direction." For example if you choose ++2 stepping it will show the normal exposure bar and a over exp bar if you choose 3 steps it will show the under, norm, and over exposure bars. Each time you take a shot one of the bars will be removed (depending on order setting).
 -1.0 AE |
 norm AE |
 +1.0 AE |
There's an interesting bracketing feature invoked when the camera is in multi-shot mode. Hold down the shutter and it will fire off all of the shots necessary to perform bracketing and then stop. For these shots the D70 was set for AE only, 3 steps, and 1.0 exposure per step. The camera was on a tripod and I simply held down the shutter and let multi-shot rapidly take all three exposures.
Clicking an image will open the full sized version in another window. These are images straight from the camera, no processing. Each image is about 1.5MB and was taken in medium sized, fine mode.
In AE mode the step sizes can be as small as 1/3 to as large as 2.0. I tried 0.3 and 1.0 in this test, showing the later here because the changes are more obvious especially at thumbnail size.
For white balance the step size choices are 1, 2, or 3. The thumbs below were taken with white balance bracketing set to 3 under a somewhat dim tungsten light bulb. Larger images aren't available.
-3 WB |
norm WB |
+3 WB |
Here's another use for bracketing that I hadn't even thought of, illustrated nicely by this series from Max Lyons. If you find part of an image over or under exposed you can "blend" a better version of that section from one of the bracket shots using Photoshop.
If you haven't heard of Mr. Lyons he has been making some very cool, large photos by combining multiple images. Check out his gigapixel image and the latest series from Washington.
A person could, should the person be so inclined, take the standard nose height of a North American Ground Squirrel as a guage in measuring the length of a rain drop trail, work backwards to distance travelled using the speed of said raindrop under normal earth gravity and thereby compute the shutter speed of the image.
Average speed of raindrops = 10mph.
Guessed length of raindop trail = 1 inch.
10 mph = 180 inches per second.
Shutter speed = 1/180 second.
Excellent!
1/200 second according to the EXIF data.
Do I win a prize? ;-)
Sure, sure. It said anonymous, not hieronymus.
How about a free squirrel picture?
This site clocks a raindrop at 11mph or 200 inches per second.
http://www.icr.org/goodsci/bot-9710.htm
Try this site for more realism:
http://www.grow.arizona.edu/Grow--GrowResources.php?ResourceId=146
And here's the last word, including formulas:
http://www.newscientist.com/lastword/article.jsp?id=lw635
Cute little bugger!
That's a nice arrangement. How did you get the critter to agree? Bribed with nuts?
How's that saying go:
"There are old chippies and there are bold chippies, but there aren't any old, bold chippies."
This one was shooting for bold not old, spending most of the morning in and on the bird feeder despite the world.
I took this shot from just inside the kitchen window, about ten feet away, and also got a bunch of photos standing right next to it.
Here in the north east they are called Chipmunks. Now there is a striped ground squirrel from Nebraska (and other squirrels I know come from Nebraska...), but here it's a Chipmunk.
In Nebraska there is a striped ground squirrel, but it has 13 stripes or lines.
The following is from the NebGuide from the U of Lincoln, Nebraska.
Thirteen-lined ground squirrels are members of the squirrel family which includes chipmunks, ground squirrels, tree squirrels, prairie dogs, and woodchucks. Three other species of ground squirrels live in Nebraska, but are relatively uncommon.