[yeatzee]

The fact that my metz flash has 1/64 power option has prompted my interest in high speed photography. Has anyone tried this in-depth? Im not talking the standard water droplet photo, but perhaps more creative things. I have a couple airsoft guns from my past available. They shoot anywhere between 330-370 feet per second from the end of the barrel, and slow down fairly rapidly. Could my flash at 1/64 power give me a fast enough shutter to stop or get close to stopping the bb's? What would be the affect of throwing my pentax into the mix at 1/32 power?

Thanks

[newarts]

The fact that my metz flash has 1/64 power option has prompted my interest in high speed photography. Has anyone tried this in-depth? Im not talking the standard water droplet photo, but perhaps more creative things. I have a couple airsoft guns from my past available. They shoot anywhere between 330-370 feet per second from the end of the barrel, and slow down fairly rapidly. Could my flash at 1/64 power give me a fast enough shutter to stop or get close to stopping the bb's? What would be the affect of throwing my pentax into the mix at 1/32 power?

Thanks

Metz 48 & 58 flashes are 1/125 sec. Assuming that 1/32 power is 1/32 of maximum duration, you might expect 1/4000 sec.

A 100m/s projectile will travel 1/40 m in that time, about 25mm! Pretty far!

But mattdm says the metz flashes can be turned down a lot more; here's his data:
Metz ? Useful T.1 Flash Duration Data - Pentax P-TTL Flash Comparison
* 48 AF-1: from ¹⁄₁₂₅ seconds at full power to ¹⁄₂₅,₀₀₀ seconds at ¹⁄₁₂₈ power
* 54 MZ-4i: from ¹⁄₂₀₀ seconds at full power to ¹⁄₂₆,₀₀₀ seconds at ¹⁄₂₅₆ power
* 58 AF-1: from ¹⁄₁₂₅ seconds at full power to ¹⁄₃₃,₀₀₀ seconds at ¹⁄₂₅₆ power

If true, the 100m/s projectile will travel about 3-4mm during the flash - still too much.

If you dim the flash & underexpose, the effective flash duration might be shorter, so the above estimates might be cut by a factor of 2-3.

Dave

[yeatzee]

Metz 48 & 58 flashes are 1/125 sec. Assuming that 1/32 power is 1/32 of maximum duration, you might expect 1/4000 sec.

A 100m/s projectile will travel 1/40 m in that time, about 25mm! Pretty far!

But mattdm says the metz flashes can be turned down a lot more; here's his data:
Metz ? Useful T.1 Flash Duration Data - Pentax P-TTL Flash Comparison
* 48 AF-1: from ¹⁄₁₂₅ seconds at full power to ¹⁄₂₅,₀₀₀ seconds at ¹⁄₁₂₈ power
* 54 MZ-4i: from ¹⁄₂₀₀ seconds at full power to ¹⁄₂₆,₀₀₀ seconds at ¹⁄₂₅₆ power
* 58 AF-1: from ¹⁄₁₂₅ seconds at full power to ¹⁄₃₃,₀₀₀ seconds at ¹⁄₂₅₆ power

If true, the 100m/s projectile will travel about 3-4mm during the flash - still too much.

If you dim the flash & underexpose, the effective flash duration might be shorter, so the above estimates might be cut by a factor of 2-3.

Dave

ideally, id like something like this:
National Geographic Magazine - NGM.com

I dont mind the projectile being blurred, but its affects i'd like to be stopped. obviously the less blurriness of the projectile the better, but im just going to work with what I've got.

any suggestions? I assume the best setup would be in a dark room, with the flash being the only light reaching the sensor, correct? What shutter speed on the camera am I looking at?

[newarts]

The fact that my metz flash has 1/64 power option has prompted my interest in high speed photography. Has anyone tried this in-depth? Im not talking the standard water droplet photo, but perhaps more creative things. I have a couple airsoft guns from my past available. They shoot anywhere between 330-370 feet per second from the end of the barrel, and slow down fairly rapidly. Could my flash at 1/64 power give me a fast enough shutter to stop or get close to stopping the bb's? What would be the affect of throwing my pentax into the mix at 1/32 power?

Thanks

An easy way to try it is to make a target that closes a circuit when the projectile hits it. One easy scheme is to put a 1/4" hole in a piece of paper and tape aluminum foil tightly over both sides of the hole, tape a wire onto each piece of foil.

The foil will be your switch. Aim at the hole. When the projectile penetrates the foil it will bring the two pieces of foil into contact and the flash will fire.

You can build in a delay by putting a small relay in the circuit. The relay will give a few milliseconds delay before firing the flash.

The next step in complexity is to make or buy an acoustic trigger that closes an electronic switch when it hears the gun. The time delay from when the gun fires is determined by how far the microphone is from the gun.

Good luck,

Dave

[jbinpg]

Triggering the flash on trailing curtain closure would help freeze the projectile.

[alohadave]

Triggering the flash on trailing curtain closure would help freeze the projectile.

1st or 2nd curtain has no effect in high speed photography. It's only useful when you want to show natural looking streaks of light or motion when using longer exposures.

For high speed, your flash duration is incredibly short, and will freeze the subject no matter when it fires.

[vicentesagredo]

most important is the synchonisation between projectile and shutter...
if its at 1/4000th a second, then a reaccion time of 0.1 seconds is about...mmm 400 attemps??

[yeatzee]

well I tried it out today real quick, and in the process broke my main macro diffuser and my brand new metz flash fell from the counter somehow resulting in what I think is a broken piece inside. All of that, and I didn't get one decent shot.

[Ash]

Sorry to hear Tanner.
Hopefully the flash will still be fully functional for you.