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Just beginning with photography.

Consider this image:

enter image description here

(This photo was taken by Harold "Doc" Edgerton in 1964 using his Rapatronic camera.)

I am looking for a camera that can capture such an image.
I am not looking for more fps. less fps is fine, but it must be able to capture such an instance.

What features should I look in such a camera? How fast should be the shutter speed? What other things I should look for?

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This photo is the classic taken by Doc Edgerton (en.wikipedia.org/wiki/Harold_Eugene_Edgerton) who pretty much invented strobe photography. –  Paul Cezanne Aug 13 at 13:05
    
See iconicphotos.wordpress.com/2009/08/19/edgerton-rapatronic -- 1/1,000,000th of a second strobe speed. –  Paul Cezanne Aug 13 at 13:08
    
@PaulCezanne kindly edit my question, and put this info in photo credit. Thanks –  gpuguy Aug 13 at 13:09
1  
Another thing you need to consider: where does the bullet go afterwards? –  Simon Kuang Aug 14 at 1:11
    
gpuguy - Here are a collection of Doc's 'iconic images' edgerton-digital-collections.org/galleries/iconic anbd here is a subset of some "bullets and blasts" ones edgerton-digital-collections.org/galleries/iconic/bullets | If you really aspire to doing things like this you'll want to work up from easier ones, and "cheating" with "as slow as you can manage while maintaining realism" bullets will help you greatly. If you can get down to the say 300 fps range then the required 10 uS or so flash window would still be "very hard", at least. –  Russell McMahon Aug 14 at 13:39

3 Answers 3

As Michael said, shutter speed is largely irrelevant – flash duration and timing relative to bullet passage is what counts. Shutter speed can be as SLOW as is helpful – maybe even "bulb".

Assuming that the photos is not doctored:
Bullet speed should be arranged to be as slow as possible without adversely affecting the affect on the target. Bullet needs to not move appreciably during exposure. So, how long (or short) does the exposure need to be?

Say bullet was travelling at 100 feet per second.
Bullet is ~~~ 1 inch long
and has moved a maximum of 5% of its length – maybe less.
So time = 1 inch x 5% / 100 feet/sec
= 1/24,000 th of a second or
~= 40 μS.

At 1000 fps that would be 4 μS.
1 μS would be even better.

Will a Xenon flash tube do this?

Wikipedia - flashtube

  • Discharge durations for common flashtubes range from 1 microsecond to tens of milliseconds, and can have repetition rates of hundreds of hertz. Flash duration can be carefully controlled with the use of an inductor.

See reference to PerkinElmer catalogue below.


Will an LED Based "flash" do this?

Achieving this sort of result with LED lighting would require significant power levels.
eg assume 1 lux, 250mm x 200mm illumination area, 10 μS exposure, 100 ISO, f 1/1 (trust me)
EV = t = 10-5
For real world results if we want say EV = 100 at f/1.4 we need illumination of
Ev_100/EV_1 x 1.4² / 10-5 = 2 x 107 lux (!)
Over an area of 250mm x 200mm = 0.05 m² that's
2 x 107 x 0.05 = 106 lumen
Leading edge Top LEDs manage around 200 lumen/Watt so power =
106/200 = 5,000 Watt of LED illumination (!!!).
In practice this is only required for 10 μS so actual power is a fraction of a Watt BUT the LEDs MUST be able to produce the peak power level required   and modern white LEDs have a peak: continuous ratio of typically less than 2:1.

So – "not really", so far.
Whereas, a suitably designed Xenon flashtube can be capable of producing these very high levels of power for extremely short periods.


Exceedingly nice PerkinElmer technical guide High Performance Flash and Arc Lamps

Says:

enter image description here

Figure R, page 13


Added:

As Paul said, the photo was produced by the late Harold Edgerton and is one of the ones he is most known for. You need to study his website re methods and equipment.

Alas, the flash duration that I calculated above by rule of thumb was just about right   and my "nice" value was spot on   one millionth of a second. Have a look at the PerkinElmer catalog for what you'll need.

This famous photo of Harold Edgerton's is specifically identified as having a 1/1,000,000th second exposure time.

enter image description here

http://2.bp.blogspot.com/-QsMQtqyM4SE/UEKMd9LJsbI/AAAAAAAAyrY/nCMWxq-oY84/s640/Harold-Edgerton-27.jpeg

See also:

Harold "Doc" Edgerton Collection website

HE - stroboscopic method

Bullet through banana

Many here


E&OE - it's late and there is still work to be done. I may very well have dropped or added a power of 10 or few above or done something really silly - by all means do point out any errors.
Be kind :-)

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" Bullet speed should be arranged to be as slow as possible" , how to arrange this. Can you elaborate on this point? I did not get it. –  gpuguy Aug 13 at 12:52
3  
@gpuguy Bullet speed depends on load used. People accustomed to reloading bullets will be able to produce a "load" with a muzzle velocity well below what is normal for a given calibre firearm. Most real world weapons achieve MVs in 1000-4000 fps range. That's above my upper v of 1000 fps. A very light load indeed is liable to be in order - the apple will probably still die . chuckhawks.com/rifle_ballistics_table.htm –  Russell McMahon Aug 13 at 13:26
1  
@gpuguy If you don't know anyone who reloads and is willing to spend a fair amount of time in trial/error work to figure out how low the gun you're using can go while still working well (abnormally low velocities can cause reliability problems; mostly for semi-auto designs); looking for sub-sonic ammunition will get you on the bottom edge of what's available commercially (mostly this will be for older low power handguns). –  Dan Neely Aug 13 at 21:04
    
We can't reduce it to 100 feet per second though, that's slower than paint balls - the answer is off by at least ten times. All my handguns are over 1000 feet per second, the rifles in the 3000-3500 range. Just add a zero to every number in the answer. Also, please add some safety information - NEVER place yourself in front of a live firing line. Put your equipment out there and risk it getting shot, but don't you be anywhere in front of firearms. –  Jasmine Aug 13 at 23:42
2  
@Jasmine Doesn't getting the muzzle velocities wrong by a factor of 10 indicate that Russell isn't really qualified to give that information? Also, I think it's implicit that people should take appropriate safety precautions whatever they're doing. For example, advice on landscape photography isn't peppered with "Don't fall off cliffs. Be careful about dangerous animals. Bring adequate supplies if you're in the wilderness. Check the weather forecast." and so on. –  David Richerby Aug 14 at 11:03

The camera doesn't matter. In high speed photography such as this photo it is all about the speed of the flash and being able to fire it at precisely the correct moment. The flash is usually fired with an electronic trigger that reacts, after a specific delay of several milliseconds, to the noise of the gun firing . The camera's shutter can remain open for several seconds before and after the exposure because other than the flash the room is totally dark.

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For this image, what should be the flash/shutter speed ? –  gpuguy Aug 13 at 12:33
4  
"The camera's shutter can remain open for several seconds before and after the exposure" - the flash is providing all the light, so it doesn't matter. –  Philip Kendall Aug 13 at 12:35
1  
9x19 has velocity of 390 m/s and about 1cm in length if you can tolerate 5mm motion blur you would need 0.005/390 ~ 1/80000s flash speed. –  Andrew Aug 13 at 12:38
    
@gpuguy (1) As Michael said, shutter speed is largely irrelevant. = slow enough. Maybe even "bulb". (2) Assuming that the photos is not doctored: Bullet speed should be arranged to be as slow as possible without adversely affecting the affect on the target. Say bullet was travelling at 100 feet per second. Bullet is ~~~ 1 inch long and has moved a maximum of 5% of its length - maybe less. So 1 inch x 5% / 100 feet/sec = 1/24,000 th of a second or about 40 uS. At 1000 fps that would be 4 uS. 1 uS would be even better. .... –  Russell McMahon Aug 13 at 12:40
2  
@gpuguy - not those specs, no - they tell you how bright and what it connects to but not for how long. Flash duration or speed is often measured as the time the flash takes to get from full power to half power or 10%. Also called t/0.5 and t/0.1 times. photo.stackexchange.com/questions/1620/what-is-flash-duration would be the place to look, and maybe the answer there needs some more attention. –  James Snell Aug 13 at 13:34

This photo was taken by Harold "Doc" Edgerton (see http://en.wikipedia.org/wiki/Harold_Eugene_Edgerton) in 1964 using his Rapatronic camera. He used a strobe speed of about 1/1,000,000th of a second. See http://iconicphotos.wordpress.com/2009/08/19/edgerton-rapatronic/

The bullet was traveling at 2,800 feet/second.

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