Help getting flash slave unit working...

neo2810

neo2810

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*** JUST REALISED THERES A LIGHTING SECTION SO POSTING A DUP IN THERE... CAN A MOD PLS DELETE THIS THREAD?***

Some help if you please?

I've got a studio setup with 2 Interfit flash units as main and fill flashes positioned at 45deg left and right rear, and a 430EX front left aiming at the white backdrop to bleach it.
My 40D is connected to the main flash unit via sync cable, and the 2nd Interfit unit is triggered by the first flash (built in slave cell). That lot works fine...

I've got a Kood hotshoe slave unit connected to the 430EX on a tripod but cannot figure out how to get it to trigger from the other 2 flashes? (the slave unit has a light sensitive trigger jobbie on it). I assume the 430EX has to be set to slave, but can't get it to work... Where am I going wrong? :shrug:

Any help would be much appreciated....
 
I can't answer your question but why not just connect your 430Ex to your camera? The flash will trigger your Interfits - end of problem surely...

BTW, fill lights only produce fill when placed on the camera axis. if you put the 2nd light on the other side to the main light it isn't a fill, it's just an extra (and unreal) sun.
 
Surely a 2nd light as described above is still a fill light because it is filling the shadows caused by the main light.

As for it not triggering using the optical slave is it in line of sight of one of the other flashes? Is something blocking it? Lastly and apologies if this is teaching you to suck eggs but have you left it in ttl mode? Doing so might prevent it from firing if the flash only recieves a signal from the centre pin.
 
Kev M said:
Surely a 2nd light as described above is still a fill light because it is filling the shadows caused by the main light.
Click to expand...
No. A fill light is a light which reaches all parts of the subject as seen by the camera. A light in any other position only illuminates part of the subject, so doesn't reach some of the areas in shadow.

Example: Key light 45 deg to side and higher than subject - result shadows under eyes, nose and lips on the lit side, unlit side totally in shadow. 'Fill' light in opposite position, exactly the same result in reverse. neither light reaches the shadow areas caused by the high position of the other light.

Fill light, on axis with the lens and as close to it as practicable reaches all parts of the subject, so fills all shadow areas.

Not that fill lights are always what's needed of course, just that when they are, that's where they go. Placing the light in the opposite position is unfortunately very common, and often encouraged by our wonderful camera magazines:shake:
 
Garry Edwards said:
I can't answer your question but why not just connect your 430Ex to your camera? The flash will trigger your Interfits - end of problem surely...

BTW, fill lights only produce fill when placed on the camera axis. if you put the 2nd light on the other side to the main light it isn't a fill, it's just an extra (and unreal) sun.
Click to expand...

Not according to most lighting diagrams I've looked at. They all refer to the right flash as main and the left flash as fill? :shrug:

This is what I'm doing:

Untitled-1.jpg


The little 430EX near the background is to bleach it. Couldn't really do that with it attached to the camera...
 
Thanks Kev... 430EX is set to manual, 1/1 and neither high speed sync nor 2nd curtain sync selected. The main flash points directly at the slave unit pretty much so by all intents it should trigger? I've tried the flash in normal mode (as if it were attached to the camera) and in slave mode to no avail.. Is the hotshoe slave unit fubar'd?
 
I bought an off camera flash cord as well which woul be fine if it was longer than 1.4m... grrrr
 
Mystery solved... Canon 430EX does not work with most 3rd party optical slave units. Apparently Canon didn't add the option to their Flashes, and the preflash messes with the optical unit... It will be going back to the know-it-all shop assistant who mis-sold it to me knowing I was using it with a 430EX....

Apparently the only one which works is the Wein Digital Smart Slave but I can't find definte confirmation of that...

Ho hum, looks like I'm going to have to fork out for a wireless system....
 
neo2810 said:
Not according to most lighting diagrams I've looked at. They all refer to the right flash as main and the left flash as fill? :shrug:


The little 430EX near the background is to bleach it. Couldn't really do that with it attached to the camera...
Click to expand...
I accept that most lighting diagrams give wrong info. I'm just giving you right info. Don't take my word for it, try it for yourself. Experiment and see what works for you and what doesn't, see what works for your subjects (no two people ever have exactly the same shape of face and all that your lighting diagram does is to give everyone a fat face) and what doesn't. Lighting according to lighting diagrams is about as creative as painting by numbers:lol:

I assumed that your flash synch cord was long enough to reach. if it isn't then my suggestion won't work.
 
Garry,

I wasn't knocking your advice or questioning your expertise (your advice is much appreciated). I was more questioning the general info floating about... Thanks for clarifying.

I'll be taking the off camera flash cord back and trying to find a 3m one if I can. That will solve things.

As for the lighting setup, appreciate the tip. I'll be shifting the lights around all over the place to test different positions so no doubt I'll find some joy in a few. Keen to try some rim lit shots as well while I'm at it...
 
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