ST-E2 timing

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I finally gave up trying to use my 550EX's for studio portraiture, even for simple tasks like hair and background lights, and bought two more monolights. There just isn't enough reflectivity in some cases and the flashes weren't always going off.

Now then, I really hate the idea of using a pc cord since I tripped over one a couple of months ago and pulled my EOS 3 and 28-135IS off a table and onto the floor (no damage to either, TG).

Radio slaves would seem to be overkill for the small working space I have and something like Wein's IR transmitter would seem to be duplicating my ST-E2.

So...I've done some tests using my ST-E2 to trigger an optical slave and it works BUT there seems to be a timing problem. A test roll of film came out blank even though the lights were going off. Pressing the shutter with no lens attached and the camera back open, shows me the entire frame so I'm not sure what's happening. I normally shoot at the max sync speed (1/180 using half-stops). Would reducing the shutter speed help, and if you think so, how much do you think it will take?

Thanks,

Paul

-- Paul Ferrara (paul@columbusoft.com), October 19, 2001

Answers

A further thought! Would putting tape over any of the contacts in the hotshoe make the camera treat the ST-E2 as a non-dedicated flash and get rid of the lag?

-- Paul Ferrara (paul@columbusoft.com), October 20, 2001.

Another thought: how about using 2nd curtain sync?

-- Paul Ferrara (paul@columbusoft.com), October 20, 2001.

The 550EX is a portable "pocket" flash and can't be compared to real studio strobes. Moreover, the max sync speed of the EOS 3 with studio flash is 1/125 sec, not 1/180 (see p. 101 of your manual). So, I'd give that a go and it should work better.

Aloha

-- Puppy Face (doggieface@aol.com), October 20, 2001.


Thanks for pointing that out. I'll try 1/125 and a couple of slower ones also. I oughta point out though that the sync is fine at 1/180 as long as I use a sync cord or one of the 550EX's trigger the slaves on the monolights. It's only when I try to trigger the slaves with the ST-E2 that I have the problem. I'm going to run off a few frames in a couple of hours testing the lower shutter speeds and 2nd curtain sync.

Paul

-- Paul Ferrara (paul@columbusoft.com), October 20, 2001.


I doubt it will work. The ST-E2 uses IR pulses to communicate with the 550EX before the exposure. I think this is what is tripping the slaves before the shutter even opens. You might even be able to see the strobes fire in the viewfinder BEFORE the mirror raises to block out the viewfinder.

Most/all optical slaves are very sensitive to IR. Wein's IR transmiter will trip any slave, not just their IR slaves. I have one and it trips every optical slave I have. On the flip side, you can use any small shoe mounted flash with a deep red filter taped to it, to trip the studio strobes.

-- Jim Strutz (j.strutz@gci.net), October 20, 2001.



Jim, you were correct as usual (although I hoped you missed this one ). All frames are totally blank. Guess I'll just forget about using the ST-E2 for this purpose.

Can you be more specific on your red filter recommendation? Were you thinking of something like a Wratten filter?

Thanks,

Paul

-- Paul Ferrara (paul@columbusoft.com), October 20, 2001.


Jim, would this do it?

Kodak 3x3" (75mm) Deep Red #29 for Tricolor/Color Separation Work Gelatin Filter

-- Paul Ferrara (paul@columbusoft.com), October 20, 2001.


I've never used the red filter idea, I just heard it would work, so I'm not sure what filter is best, but I doubt you could get too red.

The Wein SSR transmitter uses two AA batteries, recycles amazingly fast and trips every optical slave in the area, no matter where I put them. It doesn't seem to be very directional. It also has a low sync voltage so it's safe on EOS cameras. It's not cheap but it does work well.

I have used it to trip my 550EX mounted on a Ikelite lite-link. I guess it's designed for the extremely sensitve SSL slaves, and they work well with it, but it works for what else I have too.

-- Jim Strutz (j.strutz@gci.net), October 21, 2001.


I guess the SSR is the way to go. Thanks for your help, Jim.

Paul

-- Paul Ferrara (paul@columbusoft.com), October 21, 2001.


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