HiViz Photogate trigger and 580ex

[RuggerJoe]

Has anyone out there used the HiViz photogate triggers with a 580ex? I was building the circuit yesterday and when testing the delay circuit I could only trigger the flash once. Re-tripping the circuit would not fire the flash again. In fact it seems that I can't even fire the flash from the test button on the back of the flash. All the buttons seem to be disabled until I turn the flash off and on again or I disconnect it from the circuit.

I thought that the hot shoe I'm using my have been shorting out some of the other contacts on the flash foot, but I've taped them off to make sure that wasn't happening. I'm pretty sure I have the polarity of the hot shoe right, but I'm going to double check that tonight. Any suggestions?

[mbellot]

Just a guess, but this could be related to all the trouble the Canon flashes have with optical slaves.

If the trigger circuit doesn't (or can't) "let go" of the trigger terminal to create an open circuit again you won't be able to re-trigger. This could be caused by too much leakage current from the flash, which would force the SCR thats triggering it to stay on.

I'll take a look at the HiViz website and see if anything "pops". :lol:

[RuggerJoe]

This is the instructions for the Kit i have. But there is no schematic. I've only built it up to stpe 9, testing the delay circuit. I did find a post online about one of the not being wired in the right spot in the instructions comapred to the circuit diagram, the 10 µF Capacitor next to the pot in the picturehttp://www.hiviz.com/kits/instructions/spg1-du-manual.htm But that only affect the delay timing and didn't affect anything else.

I believe this is the right circuit diagram based on my rudimentary electronics knowledge and what I can remember from the board sitting at home. http://www.hiviz.com/tools/triggers/triggers4.htm

I'm also still waiting on a reply from HiViz.

[mbellot]

Joe,

If you have access to other resistors (Radio Shack being a likely suspect if you have none lying about), I would try inserting a resistor in series with the two outputs.

Start low (100 ohms or so) and go up in value until one of two things happens.

1. The flash starts to recycle because there is now insufficient current to hold the SCR "on" (desired result)
2. The flash never fires because there is now insufficient trigger voltage drop. (undesired result)

[RuggerJoe]

Radio Shack has 1/4 watt and half 1/2 watt. Does it make a difference which I get?

[mbellot]

Radio Shack has 1/4 watt and half 1/2 watt. Does it make a difference which I get?

Nope. The voltages and current involved should make 1/4w resistors fine, 1/2w will just be even more overkill.

[mbellot]

Hey Joe, another thing occurred to me...

Since you're only using the 580EX, and not a HV trigger voltage strobe, you might be able to switch the SCRs out for transistors.

I'll do some more thinking on it when I get a chance, but it might be a better solution.

[cosworth]

Is this flash in ETTL mode? My optical slave fires multiple times on a 580 without issue.

[mbellot]

Joe,

Transistors should work, and probably more reliably.

Here is a variation on the schematic you linked. The important differences are the 2n2222a transistors instead of the SCRs and the lower base resistors (the gate resistors on the SCRs was 22k, the transistor base resistors are 1k). If you want to provide a little protection to the transistors you could insert a 10 to 100 ohm resistor in series with the output(s).

You don't need R7 or R9, they were only there to provide some current through the transistors during simulation - thats what your flash should do.

Sorry about using two 555s, I didn't have a model for a 556 handy.

Cosworth: Are you using the Wein Peanut? I understand people are having better luck with that over the older/larger Wein unit.

[cosworth]

Nope, I have the sonia optical slave. Works great as long as you are not in hard sunlight.

as seen on ebay:

http://cgi.ebay.ca/Optical-Slave-Flash-Trigger-Digital-Wireless_W0QQitemZ330102288014QQcategoryZ30084QQcm dZViewItem

[mbellot]

Nope, I have the sonia optical slave. Works great as long as you are not in hard sunlight.

as seen on ebay:

http://cgi.ebay.ca/Optical-Slave-Flash-Trigger-Digital-Wireless_W0QQitemZ330102288014QQcategoryZ30084QQcm dZViewItem

Interestingly enough, half way down the auction page you find this:


For CANON EX USERS: Canon EX series flashes tend to freeze if you try to fire them by mounting an EX flash on those triggers (when you are using EX flashes as slave flashes) – (an EX flash mounted on your camera to trigger another flash on the slave trigger is no problem whatsoever). This problem is not consistent but very frequent, and I do not know an explanation or solution for it. Please see Sarah Fox’s website (http://www.graphic-fusion.com/equipment.htm#slaves) where she describes her solution but I also got reports that people had difficulty replicating her efforts. I have to acknowledge I’ve given up on this problem, and you do it on your own risk if you plan to trigger Canon EX flashes. Canon EZ flashes and all earlier models have no problems whatsoever. No other flash has been reported to have similar problem

You must be in the lucky minority.

[cosworth]

mbellot, I'm taking some video right now with my P&S... hang on.

[FlashZebra]

Nope, I have the sonia optical slave. Works great as long as you are not in hard sunlight.

as seen on ebay:

http://cgi.ebay.ca/Optical-Slave-Flash-Trigger-Digital-Wireless_W0QQitemZ330102288014QQcategoryZ30084QQcm dZViewItem
Cosworth,

Are you using your Sonia optical slave on that hotshoe adapter shown in the ebay ad you cite?

I did not use that particular hotshoe adapter device with the several Sonia optical slaves I tried, but my Sonia optical slaves would not work with a Canon 550EX (lockup after first flash). The Sonia optical slaves I used look just like the ones in the ebay link you provided.

If so, the hotshoe device may be the answer to why you have been able to get your Sonia optical slave to work, and others have not.

The Sonia hotshoe adapter evidently is something more than just available hardwired connection points (as with most hotshoe adapters) it indicates on this Sonia web link below that the hotshoe has "With Built-in Control Diode".

See:

http://www.soniaphoto.com/products.php?cno=35

Do you have any way to try your Sonia optical slave without using that hotshoe adapter?

Another possible explanation, the ad copy from the Sonia site indicates a "high range" unit. The units I have are not the high range version, despite the fact that they look identical.

Thank you for any help you can provide in clearing up this mystery.

Enjoy! Lon

[RuggerJoe]

OK I'm home and have had some time to play. A 4700 Ohm resistor does not let it reset and a 10k Ohm resistor won't let it fire. I have nothing in between. However if i put a 4700 and a 1k resistor in series (on after another) I will have 5700 Ohms, correct?

[RuggerJoe]

Damn, I wish I payed attention in my electronics class.

Joe,

Transistors should work, and probably more reliably.

Here is a variation on the schematic you linked. The important differences are the 2n2222a transistors instead of the SCRs and the lower base resistors (the gate resistors on the SCRs was 22k, the transistor base resistors are 1k). If you want to provide a little protection to the transistors you could insert a 10 to 100 ohm resistor in series with the output(s).

You don't need R7 or R9, they were only there to provide some current through the transistors during simulation - thats what your flash should do.

Sorry about using two 555s, I didn't have a model for a 556 handy.

Cosworth: Are you using the Wein Peanut? I understand people are having better luck with that over the older/larger Wein unit.

[FlashZebra]

OK I'm home and have had some time to play. A 4700 Ohm resistor does not let it reset and a 10k Ohm resistor won't let it fire. I have nothing in between. However if i put a 4700 and a 1k resistor in series (on after another) I will have 5700 Ohms, correct?
Yes, a 4700 Ohm and a 1000 Ohm (1 K Ohm) in series will net a combo equal to one 5700 Ohm resistor.

Enjoy! Lon

[cosworth]

ok here:

http://photography-on-the.net/forum/showthread.php?p=2957339#post2957339

[RuggerJoe]

Well it looks like 5700 Ohms did the trick. Now I have to figure out where to fit 4 resistors onto an already cramp bread board. Although if I put the resistor on the ground side of the PC cord I guess I only need 2.

[RuggerJoe]

Wohoo! It works! Thanks for your help guys!

Still waiting for a reply from HiViz. Not exactly supper impressed with their customer support. I emailed them a couple days ago about something else and haven't even gotten a response from them on that yet. Oh well it works. Now I just need to put it in a project box. Forgot to get a couple at Radio Shack when I was there.

[mbellot]

Well it looks like 5700 Ohms did the trick. Now I have to figure out where to fit 4 resistors onto an already cramp bread board. Although if I put the resistor on the ground side of the PC cord I guess I only need 2.

Joe,

You should be able to get 5.6k resistors at the Shark when they open tomorrow.


Damn, I wish I payed attention in my electronics class.

No choice, I'm designing electronics every day. If I can't figure this out I better sign up for a paper hat and start practicing "You want fries with that?". :lol:

I do believe the transistor approach would be better as long as you're using low sync voltage strobes like the 580EX, but if it works thats what counts.

[milleker]

Glad to see you got it working Joe, as for an e-mail back from HiViz, the person who runs the shop is a teacher that does this more as a hobby - you'll get an answer, but maybe not until Monday. I guess a price to pay for very inexpensive kits that work great.


Wohoo! It works! Thanks for your help guys!
Still waiting for a reply from HiViz. Not exactly supper impressed with their customer support. I emailed them a couple days ago about something else and haven't even gotten a response from them on that yet. Oh well it works. Now I just need to put it in a project box. Forgot to get a couple at Radio Shack when I was there.

[RuggerJoe]

Well the 5.7k resistor didn't do the trick after all. Seemed to work ok on the instant output, but didn't work on the delayed output. So after an afternoon of switching my flash on and off I got these. http://farm1.static.flickr.com/220/445499874_1c50c30067_o.gif

[milleker]

Joe, very cool!

You've got a working solution now, but I'd keep an eye on eBay for a Vivitar 283. You can get them for around $50. Theres also a company that makes a plug for the flash too for a few bucks - that'll interface right into the kit. Or you can get fancy and hard-wire it into the hotshoe.

[mbellot]

Well the 5.7k resistor didn't do the trick after all. Seemed to work ok on the instant output, but didn't work on the delayed output. So after an afternoon of switching my flash on and off I got these.

Cool!

Joe, you should give the transistors a shot - they'll save a lot of wear and tear on your power switch.

A quick check of RadioShark pops up two good parts, the MPS2222A (276-2009) and 2N3904 (276-2016).

I may have to see if I've got parts laying around the office, this looks cooler than I expected.

[Schipperke]

From the hiviz website:

*Customers have reported that when using the delay unit outputs to trigger Canon 430ex and 580ex flash units, the flash unit is disabled after each discharge until the unit is turned off and on again. In order to correct this problem, two 1-kW replacement resistors are included with each delay unit and combination kit. These resistors may be used in place of the 22-kW resistors that lead from outputs 5 and 9 of the 556 timer.