question for 580ex users

chrismoore

Hi, I'm going to experiment with high speed photography using a DIY sound trigger. I am going to shoot various objects in the dark using a 2 second exposure on a canon 5D and the sound of the pellet gun will trigger the 580ex flash to "freeze" the object blowing up. I did some test runs and even when holding the pellet gun right up to the object, the secondary sound of either the shattering, or the glass hitting the ground is triggering the flash to trip a second or third time which ruins the shot. Because its a DIY trigger, it is very difficult to control what amplitude of sound actually trips the flash, so I was wondering if there was any way to adjust the latency period between flash firings on the flash itself. any ideas?
Thanks

pyry

chrismoore wrote:

Hi, I'm going to experiment with high speed photography using a DIY sound trigger. I am going to shoot various objects in the dark using a 2 second exposure on a canon 5D and the sound of the pellet gun will trigger the 580ex flash to "freeze" the object blowing up. I did some test runs and even when holding the pellet gun right up to the object, the secondary sound of either the shattering, or the glass hitting the ground is triggering the flash to trip a second or third time which ruins the shot. Because its a DIY trigger, it is very difficult to control what amplitude of sound actually trips the flash, so I was wondering if there was any way to adjust the latency period between flash firings on the flash itself. any ideas?
Thanks

Unless you can change the trigger circuit to give just one pulse, you could try putting the flash on Multi - the slowest cycle should be 1 Hz and you can set the number of pulses to one.

(note though: this is on a 550EX, but I think all this should work on a 580)

chrismoore

pyry wrote:

Unless you can change the trigger circuit to give just one pulse, you could try putting the flash on Multi - the slowest cycle should be 1 Hz and you can set the number of pulses to one.

(note though: this is on a 550EX, but I think all this should work on a 580)

That is a great idea, but unfortunately when put to use it doesn't work. The sound trigger overrides any flash settings and will send a trigger to the flash whenever the sound registers, regardless of any manual settings. I was able to avoid the double burst by shooting the gun at the very end of the exposure, and changing the distance of the sound trigger from the subject. Lots of fun for my first go round, will definitely try again sometime (my wife wasnt too thrilled about the mess I created).

Scott_Quier

Those are some seriously cool shots! Well done, indeed!

Qarik

chrismoore wrote:

Hi, I'm going to experiment with high speed photography using a DIY sound trigger. I am going to shoot various objects in the dark using a 2 second exposure on a canon 5D and the sound of the pellet gun will trigger the 580ex flash to "freeze" the object blowing up. I did some test runs and even when holding the pellet gun right up to the object, the secondary sound of either the shattering, or the glass hitting the ground is triggering the flash to trip a second or third time which ruins the shot. Because its a DIY trigger, it is very difficult to control what amplitude of sound actually trips the flash, so I was wondering if there was any way to adjust the latency period between flash firings on the flash itself. any ideas?
Thanks

awesome shots! let me understand what you are saying...in the 2 sec exposure you are getting multiple flashes which you don't want? try a rear sync on the flash? not sure what the limitation on that is.

RBrogen

I have GOT to try this! this is awesome. Can you elaborate on your DIY sound trigger pls?

chrismoore

RBrogen wrote:

I have GOT to try this! this is awesome. Can you elaborate on your DIY sound trigger pls?

Would be happy to! A lot of my friends wanted more info so I wrote a blog entry outlining the set up, and luckily took a photo of everything before I started shooting. All the info here. Let me know if you have any questions. My wife is leaving town in a couple of weeks and I'm going for round two!

Sam

I just spent about 20 minutes on your website. Very, very nice!!

Sam

Chile Chef

WOW, oh wow, Those are very cool shots chrismoore.

Could you help out a newbie in this field and show me how you did that?

chrismoore

Chile Chef wrote:

WOW, oh wow, Those are very cool shots chrismoore.

Could you help out a newbie in this field and show me how you did that?

I documented the set up here. Good luck to anyone who tries it out, be sure to post some of your results in this thread.
My wife is going out of town in a couple of weeks and I've got some new ideas for round 2-- will make a really really big mess!

chrismoore

Sam wrote:

I just spent about 20 minutes on your website. Very, very nice!!

Sam

Thanks Sam! appreciate the kind words.