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View Full Version : At the other end of flash photography.



Mr Felix
02-01-2011, 12:29pm
One of my little "quests" is to learn how to control other lights/flashes when the shutter is pressed.

This led on to taking pictures of baloones poping, etc.

Reading more about that, it seems some of these are done in darkness and the flash is used to capture the action.

When the baloon pops, the noise causes the falsh to fire and the image is captured by the camera - which is in BULB mode.

Ok, I can see how this works. Kind of like a disco light.

I don't know if that is the ONLY way to do it, but I am sure that the action shots of other things happening in daylight - obviously - can't do it that way.

I have a Canon 550D. There is a jack and I bought a "cable" release which plugs into the camera. This is (I'm guessing) two wires and a switch.

I'm also guessing - though if the assumption before is correct then it isn't that difficult - to replace said switch with some electronics I could make it so when something happens, a signal is sent to the circuit and that tells the camera to take a picture.

I can't be THAT difficult to make.

But I don't want to take too much for granted.

Has anyone here ever done something like that?

Is this the best place to ask - as flash and strobe where I first started asking - isn't the right place for THIS question.


(Been away and come back with more thoughts.)


I am not wanting to use this system of which I am asking to take pictures of exploding baloons.


(Using basic words as the "correct" ones escape me at this time)
I am wanting it so I can set up a system where I can point a "magic beam" at (say) a bird bath.
When a bird comes in to land, the beam is broken and the camera takes a picture of the bird just about to land in/on the bird bath.

I would call it an action shot, but may be wrong.

That is the kind of thing I want to do.


Does this help clarify what I want to do and maybe someone help me build a circuit/understand what I need to do?

I @ M
02-01-2011, 1:05pm
Well, if you don't want to spend much money as you indicated in your other thread then you will have to start experimenting with sound or motion triggers and building your own setup.
Google is probably your best friend when it comes to sourcing information on those things or you could read through quite a few informative threads on here by Desmond on flash and camera triggers.

Try ---

http://www.ausphotography.net.au/forum/showthread.php?56519-Stop-motion-photography-quot-how-to-quot

and have read of his linked blog for a starting point.

Mr Felix
02-01-2011, 1:11pm
Thanks.

I tried google but maybe didn't put in the right words to get back what I wanted.

Mr Felix
02-01-2011, 1:14pm
That link - already looked at from other thread - is more FLASH controlled photos.

I am wanting to find a way for electronics to tell the camera - NOT the flash - to take a image.

Yes, I know I can buy "remote" controls for the camera. I have a "cable release" and want to know if I can hack that and use the plug/cable to connect electronics to the camera which will tell the camera to take pictures.

kiwi
02-01-2011, 1:23pm
The flash doesn't take the photo, the camera does, sound triggers fire the camera and the camera fires the flash

Re the remote, I think you'll bugger about for ages trying to replicate a $20 accessory

Just take photos instead

Mr Felix
02-01-2011, 1:27pm
Um, if you look at this link:


http://desmond-downs.blogspot.com/2010/05/stop-motion-photography.html
and read it, it says that most of the pictures are taken with the camera in BULB mode and the sound triggers the flash.
Therefore the falsh is what "takes the picture".

(Qoute from page)

If you want to freeze action you are better off using flash than shutter speed for two reasons :

1.) Flash can do faster speeds . Most cameras these days can go to about 1/4000th sec , some to 1/8000th .
Flash , with a Nikon SB800 , at 1/128th power fires as fast as 1/41600th sec .

2.) Flash can fire as fast as you need it to , shutters have a slight delay before they fire .


If you have the luxury of time then you can wait until it gets dark - or use a very dark room depending on what you will be "shooting" .

I @ M
02-01-2011, 1:32pm
Why not apply yourself to learning the "basics" and you will find that using high shutter speeds and a flash you will be able to shoot in broad daylight perfectly satisfactorily.

Mr Felix
02-01-2011, 1:36pm
I@M,

Thanks, but I am asking if people can help me with a particular thing I want to do.

It would seem I have to go to other forms and ask there, as information here is not forth coming.

No one seems to understand this parragraph I wrote earlier:
(Using basic words as the "correct" ones escape me at this time)
I am wanting it so I can set up a system where I can point a "magic beam" at (say) a bird bath.
When a bird comes in to land, the beam is broken and the camera takes a picture of the bird just about to land in/on the bird bath.

Kym
02-01-2011, 1:42pm
Mr Felix...

Whatever trigger you want is possible. It's an electronics problem, not photography.
All you need to do is buy a $10 ebay remote for your camera, and wire whatever trigger/relay into a 'hacked' remote.

The design and construction of your trigger is up to you.
There are Silicon Chip magazine kits that let you build all sorts of optical or audio triggers.

In the end all your trigger needs to do is close a circuit.

MarkChap
02-01-2011, 1:49pm
It is a dead simple thing to do, it really is, google for infra red triggers, build the circuit and away you go.
You simply build a trigger mechanism, that fires the camera when it is tripped.
You are not getting the information you want here because you want someone to tell you to go and buy xyz parts and solder part a to b and so on.
I don't think anybody here has the expertise to be that precise.

It is not difficult, really.

As for the high speed capture you refer to, if you also read Desmonds threads he tells you that he is getting around 1/25 000 th of a second effective shutter speed from his flash, you cannot achieve this with the shutter in your camera.
If you want to capture the balloon busting etc, you have no choice, you WILL have to rely on flash and triggering that at the appropriate time to get the reults. A sound trigger is easy to build, heck I think Desmond even gives you a link to the Jaycar kit that he uses. If you really read his thread, you would have plenty of information to be on the way to building this.

arthurking83
02-01-2011, 6:03pm
Also note that the idea that the flash is capturing the image is not as simple as you may believe this to be.

try capturing a landscape image using flash at 1/46500s!!

As I understand your question, the speed of the subject maybe an issue for you.
That is, if the camera has a specified delay in triggering, and your optical device is also going to have a delay in reacting, then you must factor this into the equation.
If the subject moves into and out of frame or focus with a one second period, and the reaction time of the trigger device + the camera is more than 1 sec and even say 0.5sec .. then you may not get exactly the images you were hoping for.

As Kym said .. this is not a photography related problem and many post have been made over the years that lead to links of hacked remotes and whatnot.... Google will almost certainly be a better resource, but you already have Desmond's blog on file for reference.
As Kym said too.. Silicon Chip magazine have many great project kits available for reading.. and usually for sale as DIY kits @ Jaycar.

As far as I'm aware you don't even need a cheap ebay remote for $10 for your Canon.. my understanding of Canon cameras is that they use the 2.5mm audio plug connector for the remote release.

Mr Felix
03-01-2011, 8:03am
Hi again.

In the mean time, I got out my DMM and the cable release I bought, and "buzzed it out".

Yes, it is simple. Today or tomorrow I am off to Jaycar and buying a 2.5mm stereo lead with what ever on the other end.
Shall cut that other end off and build my circuit around that as the interface.

Kym, I shy away for "evil bay" as I have heard of many people getting stung by it. Sure there are 'suckers born every minute' and probably many people DON'T get stung. But the cable from Jaycar would be cheaper than the IR remote.
The rest of the circuit is going to cost the same anyway.

No MarkChap, I wasn't expecting people to tell me exactly what to do and connect a to b, etc. Well, not in my mind. I was asking if anyone had done it and what was involved.
My original question about flashes is now "incorrect" to obtain the results I desire now.


ArthurKing
Do you understand this statement/example:
"I am wanting it so I can set up a system where I can point a "magic beam" at (say) a bird bath.
When a bird comes in to land, the beam is broken and the camera takes a picture of the bird just about to land in/on the bird bath"
I am sure that with a bit of tweaking the F-Stop I can accommodate the movement of the bird's distance and keep it in the depth of field.

Mr Felix
03-01-2011, 8:16am
As a "final" thing, this link was given to me:

http://www.diyphotography.net/release_cable_for_canon_dslr

It confirms what I now know about what does what.