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Mr Felix
31-07-2014, 6:19pm
Looking around at other ways of taking pictures, there is a way where you use the FLASH rather than the shutter to take the picture.

So basically you are in a dark room, open the shutter and when the event happens, the flash .... flashes.

So obviously it is an external flash. But the FLASH is "triggered".

Ok, I'll bite: How?

ameerat42
31-07-2014, 6:24pm
Motion sensor, sound sensor, pressure sensor...
Taste something you like?:D

Mr Felix
31-07-2014, 6:30pm
OK, "lost in translation".

How is the flash triggered, as in how do you tell the flash to flash?

Not what causes it to.... But more the actual "Flash now" signal to the unit.

ricktas
31-07-2014, 6:42pm
You buy a motion sensor that is designed to trigger a flash. The motion sensor activates and sends a signal the flash to tell it to fire. Lightning triggers work the same way. They detect lightning and tell the camera to take a photo

Mr Felix
31-07-2014, 7:03pm
I thought lightning sensors detect the ambient light.

Ok, I'm not explaining myself because I don't seem to be getting the right answers.

I've seen these "do-dads" which attach between the camera and flash, or maybe JUST under the flash and no camera connection needed.

Of course there is a cable going to that unit to trigger the flash.

I'm wanting to "explore" the inner workings of that little thingy.

Found one example:
http://triggertrap.com/products/accessories/flash-adapter/

Langers
31-07-2014, 7:31pm
Your flash receives an electronic signal telling it to fire, what sends that signal is the sensor of choice, motion, light or whatever you may choose.

Mr Felix
31-07-2014, 7:33pm
So how do I make that signal myself rather than having the camera send it?

Which "pins" on the hot-foot are used and what "signal" needs to be sent?

Looking it seems like a camera shutter signal. IE: shorting two connections.

But which two?

jev
31-07-2014, 7:40pm
All flashguns have two contacts, one in the middle and one in the outside ring. Connect those and it flashes. Easy test: take a piece of wire. Swtich on the flash unit (not on the camera!) and short-circuit the outer ring and the centre contact for a moment. Tip: don't look into the flash when you do that :tog:

Mr Felix
31-07-2014, 7:43pm
Thanks.

I probably have been told this, but have forgotten.

My little camera control is getting closer to finishing, so I am wanting to make sure all the T's are crossed and I's dotted.

:)

:tog:

jev
31-07-2014, 7:46pm
Easiest solution: get one of these: https://www.hama.com/00006952/hama-hot-shoe-adapter-cable-contact

They cost next to nothing (o, well... since it's photography related... scrap that. I'm pretty sure you can get one for under $10 at your local camerashop).

I @ M
31-07-2014, 7:53pm
If all else fails ---- there is a button on the flash called "flash" for Nikon and I think usually on a Canon it is the squiggly lightning symbol.

Push that and the flash will fire at the power settings you input to the flash unit.

It aint rocket science but you will have to have a basic understanding of exposure and flash power calculations etc.

Mr Felix
31-07-2014, 8:07pm
I @ M,

Yeah, but I want it electronically controlled. :flowersnap:

Jev,

Thanks, that looks like what I may be wanting.

I didn't know the name so I didn't know what to search for. :confused013



I'll now make inroads to that and see how to get that into the project.

jev
31-07-2014, 11:04pm
Don't misunderstand, that thing is just a connector with a wire on it eh! It just is a nice replacement for the wire used in the experiment I described earlier. A word of warning: depending on the flashgun the contacts may carry high voltages.

You'll still need something to short-circuit the wires with. Depending on what exactly you want to trigger on, you'll need a sensor that triggers a relays. The sensor very much depends on what you want to trigger on. Is it a person walking through a door? Or movement in an open space? Do you want to use a lightbeam? A tripwire? Pressure sensor?

Basically, you're still too vague on "the event" that should trigger the flash.

Mr Felix
01-08-2014, 5:56pm
Yeah, I know.

I just need the "interface".

I'll build the thing which triggers the flash.

bitsnpieces
05-08-2014, 2:14pm
I have an idea but don't know if it's what you're after - but this also depends if I understand correctly how lightning triggers work.

So a lightning trigger will detect a flash of light, and if it detects that, it'll trigger the camera to automatically fire?

If this is correct (which I think I may need to invest in one some day then), and presuming that you'll have a radio trigger for your flash (and depending on the trigger itself), would the scenario of having the lightning trigger on the camera to automatically take photos work, whilst using the remote to trigger your flash to fire?

That is, the remote which I have that connects to the camera, has a test button (and I'm assuming all do), to make sure the flashes are synced. It doesn't need to be connected on the camera for it to work. So I can hook up a trigger to my flash, set it in position, step away, and when I want a photo, click fire. So coupled with the lightning trigger, it should then see that flash and take the shot?

Of course, only reason I thought of this (and presuming I understand what you're asking for) is because it's wireless, and you have a lightning trigger for future use. :)

Mr Felix
05-08-2014, 7:54pm
Thanks "bits n pieces".

I am needing the "interface" to go on the bottom of the flash to trigger it from an external source.

That part is something I am going to have to build myself.

I am in the process of making a camera control system myself. But am also going to by a "Trigger Trap ADA" when the become available.

But I want to do this to get some experience with this task.

bitsnpieces
09-08-2014, 9:27am
Oh, I'm just a little confused what this 'interface' is lol
I'm more of a visual person unfortunately, diagrams help me understand better lol

But either way, good luck Mr Felix - hope it works out well. Make sure you post up some pictures of your rig when you're done. :)

I'm interested to see it :)

Mr Felix
09-08-2014, 10:59am
Well, the circuit to "detect" the light/sound/event is "easy", as in it is it's own circuit.

The "interface" is how it connects to the flash.

So: the thing which Jev suggested a few posts back is what I am wanting/needing.