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Post by john101477 on Dec 15, 2009 14:32:30 GMT -5
well here is a new question and delima I have. I am going with a cousin of mine to shoot black powder pistols next week. I have had my pistol for 8 years and never fired it so that should be cool but my real question is if I want to take a picture of the ball coming out of the weapon how fast should the shutter speed be? we are talking between 752 fps (feet per second) and 886 fps. any idea of a mathmatical equation to figure this out? is it possible?
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Post by Steve (FloppyDog) on Dec 15, 2009 16:21:10 GMT -5
If you use the mean velocity between these two (819 fps), you can use a ratio to calculate the distance the ball will travell within a selected shutter speed. Using a shutter speed of 1/2000, the ball will travel .4095' (about 5") during one exposure. So, even if you're quick enough with the shutter, the ball would still be a 5" long blurr. Of course, if you half the shutter speed to 1/2000, the blurr would be about 5" long etc. Here's the ratio based on a shutter speed of 1/2000. If I'm smoking crack and my math is flawed, somebody please correct me. 819'/sec = x'/.0005 sec Cross multiply.
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Post by john101477 on Dec 15, 2009 23:14:30 GMT -5
wow I have never used a shutter speed over 1/200. How did you come up with the x'/.0005 ? even at that the ball would still be in recognizable I am thinking. It might be better to get the smoking gun and maybe shop in the ball. although I think it would be cool to get it from the source. even loading light on powder might now work to well.
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Post by Steve (FloppyDog) on Dec 16, 2009 18:14:24 GMT -5
The x'/.0005 ratio is; x' is the unknown distance in feet, and the .0005 is the decimal equivelant to 1/2000 (it's easier to do the math if you convert fractions to decimals).
In this case the real challenge would be triggering your shutter at the right moment to capture the ball exiting the muzzle. This is probably humanly impossible, though you might get lucky. Generally you need special equipment for photography at this high of a speed. For this photograph, I think you're looking at PS'ing the ball into the photo.
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Post by john101477 on Dec 16, 2009 20:41:29 GMT -5
More than likely your right about having to PS the ball in if I go that route. Should be a great trip though. My cousins husband and I are headed to eagle lake to do some late season shore fishing. Last week it was 10 degrees there so I imagine it is going to be colder than heck. Then back down the hill and find a place off the beaten path to shoot at. Just gotta find my cold weather gear now lol.
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Post by Steve (FloppyDog) on Dec 17, 2009 4:49:18 GMT -5
More than likely your right about having to PS the ball in if I go that route. Should be a great trip though. My cousins husband and I are headed to eagle lake to do some late season shore fishing. Last week it was 10 degrees there so I imagine it is going to be colder than heck. Then back down the hill and find a place off the beaten path to shoot at. Just gotta find my cold weather gear now lol. Some food for thought: Maybe take a clean sheet of paper or something with you that you can put a shot ball on to photograph. (something that will let you easily copy-and-paste from later) Get some good photos of the pistols firing with the plumes of smoke etc. and PS the ball in afterward. Sure, it will be a composite but it will still look cool. 10 degrees, ouch. Back home in Montana, January is the worst time of the year for cold. Often it goes below zero and stays that way day and night for several weeks. Things are weird when it's that cold. Even small problems with things like a vehicle become big problems. Every morning, Dad and I would take a load of hay down to the pasture. We had this old mare, "Trinket" that would loom her head over me like I was her colt. I'd stand there and put my hands on her neck to warm them up. Sounds like a fun trip... wish I was going. LOL
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Post by john101477 on Dec 17, 2009 15:54:18 GMT -5
well if you ever get out this way give me a holler lol. about 10 years ago we had 2-3 weeks of -0 to -5 degrees day and night. everything froze .people were putting sprinklers in their trees with water turned up and the water would create awesome ice displays. it has not really gotten that cold in a long time but with as cold as it got a few weeks ago, we may see some very cold weather for here.
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