Add a sync port to 580 EX (DIY)

LonduckIf you could reference some of those post I would appreciate it
Iv found a couple of posts from yourself, but nothing yet with details as to why.

My understanding is anything that just closes the circuit fires the flash once, then it has to be cycled before it will fire again
Connecting it to the camera via the hotshoe sends a signal to the flash that basicly says, hey recycle, your gonna be needed again.

EDIT, I pulled out my 550ex and useing a test light I was able to trigger the flash by closing the center pin, earth circuit.
It would then recycle, and fire again, and again.
So there must be something unusualy in the circutry used in some optical triggers that prevents them from allowing the flash to recycle.


EDIT 2, I used an optical trigger I have with a PC sync socket on it on the 550ex.
Triggered with another flash the 550 fires, then dosn't recycle.
Fired with the sync connection on the optical trigger it fires, and then recycles.

Moppie, I too have been looking for the real answer for the EXs with optical slave triggers. I read many "guess" anywhere from EX's circutry are not designed for optical salves, to optical slaves do not drop the voltage low/high enough, or EXs have diffrent polarity. None of these info could be comfirmed.

I do like Lon's explaination of how we have "hard contacts" by physically shorting the center pin or use battery oprerated devices like radio triggers, and where optical triggers depend on flash to provide the power. Maybe Canon Speedlites has extra low trigger voltage, or too little current flows between the pins.

The only optical trigger I have that can consistantly fire and recycle my 580 and 430 EX is the Wein Peanut (PN), unfortunatly I don't have any other stand along optical trigger to do some crazy re-wiring/power supply type of tests. However, there are some odd behavior of the Peanut I observed that leads me to believe it has a different design than other triggers, relating to Canon EXs:

1) If I put the master 580 on a hot shoe adapter (thus everyting manual control), and connect to Peanut, when I fire another triggering external flash, the 580 will fire, but the slave 430 will not. But with the hot shoe adapter connected to the camera's sync port or the Ebay trigger, both flash will fire. Even though the Peanut can trigger each flash individually well, but it does not act as simple as shorting the center pin in master/slave mode.

2) In a different setup: master/slave--580/430 in manual mode, trigger by a sync cable. If I add a third flash into the mix that is triggered by the Peanut, lets say a Sunpak 383, the 430 would go nuts--it would either fire as the modeling light function is turn on (continue flash for 2 seconds) or not fire at all. Seems to me the Peanut is so sensitive that it catches the commanding signal from the 580 then the actual firing, thus confuses the heck out of the 430. Now if I take the peanut out of the equation, I could add a Alien Bees and/or another portable flash with built in optical slave, every light would work nicely together.

Is there a electrical engineer in the house?

Lotto wrote in post #2700966
Is there a electrical engineer in the house?

Its begining to sound like we need some one who dabbles in the arcane arts, any Wizards about?

Moppie wrote in post #2703045
Its begining to sound like we need some one who dabbles in the arcane arts, any Wizards about?

Lotto wrote in post #2700966
Moppie, I too have been looking for the real answer for the EXs with optical slave triggers. I read many "guess" anywhere from EX's circutry are not designed for optical salves, to optical slaves do not drop the voltage low/high enough, or EXs have different polarity. None of these info could be comfirmed.

Is there a electrical engineer in the house?

Moppie,

Lotto's experience is roughly equivalent to mine, and his take on the situation is also very like mine.

I have done a meaningful amount of investigation into this issue, but not to the level that I am positive about the significant dynamics of the root cause.

I am an engineer, but not an electrical engineer, but I think I would have the sufficient skills to root out the source of the problem, but I do not have the tools to do the job (likely an oscilloscope is needed). Or the desire to burn a lot of time on the issue.

This mystery just does not also rise to the level of importance that I want to commit a lot of resources to it. I don't even own a recent Canon Speedlight (I used a borrowed one for my investigations).

In short, this is an phenomenon that is mildly interesting, but I have quantified enough for my need.

So, most optical slaves just do not work with recent Canon Speedlights (but some do).

As to the exact root cause of this annoying behavior, you are on your own. There are those that have very grounded opinions based on some data collection and general expert knowledge of electrical engineering (PacAce has done some meaningful amount of investigation). But, so far I have not seen an explanation that is totally based on any sort of rigorous and thorough investigation of the exact issue. Several have part of a puzzle nailed down and a reasonable explanation based on that partial data (tempered with experience and knowledge). But, a full, totally clear picture of this issue has yet to emerge.

You seem to have an interest, possibly you would like to push the knowledge a bit with some investigations.

Also note that the preflash issue ("command signal") mentioned by Lotto in his post above is a separate and distinct issue, not directly related to the problem cited above.

Enjoy! Lon

londuck wrote in post #2703768
I am an engineer, Enjoy! Lon

That all sounded like Wizard speak to me!

I might have a bit more of a play when I get home, just hope I don't blow anything up.........

can this modification be used to fire PW transmiter attached to this sync outlet to trigger the other flashes? I want to use my 580ex on the camera hot-shoe as a fil light and PW attached to 580ex to trigger the main light(AB, Sunpak, etc).

Thanks,

Vlad

Yes it can. But you might need a right angle adapter when used on camera.

MichaelBass's mod comes out straight to the side, which does not have this problem.

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Many Thanks Lotto! That's the answer I was looking for!

Lotto wrote in post #2713767
Yes it can. But you might need a right angle adapter when used on camera.

MichaelBass's mod comes out straight to the side, which does not have this problem.

I think the Michael Bass modification uses a "SUB mini plug", not the mini plug. The SUB mini plug is smaller, so it can be placed higher on the 580EX.

But, the mini plug is a bit more utilitarian, since the very inexpensive Alien Bee flash cord will plug into the mini plug.

Enjoy! Lon

Have to save this post. Nice work and idea.

Good luck.

Can't trigger the other flashes off the camera sending from on hot shoe with PW PLUS on the cameraII!

Well, I spent a couple of hours last night working on my 430EX. At one point, I damaged the circuity of the flash near the plug. I was lucky though, and was able to solder that damaged piece back to its proper location. I think my flash is working again. It was really hard to get the mini plug to fit into the 430EX case though. I put it in at the back, opposite the side with the ON/OFF switch. It was a pain trying to get the bottom of the flash unit back together, but it finally worked.

Glad you were able to make the repairs. Although these are common mods and we take them for granted, extreme care must be taken when drilling in the plastic casing and modifying any circuitry. Some of it is a bit tricky when dealing with small spaces.

Last night I added a mini jack to both of my 580's and tested them with a friends pocket wizards. Care definitely has to be taken with the placement of the hole though as the jack, small as it is, can definitely hit some things. I also put a piece of electrical tape over any open metal parts that were in the flash just in case the jack hits any when re-assembled. The flash worked well but did not try with the flash on the camera to mimick what albolit experienced so cannot speak to that.

Just bought a vivitar 285hv on ebay and will likely change the pc or add a mini jack to that as well. Selling off a bunch of things to get my own pocket wizard set. Now that I need at least 3 units I need to make some room in my wallet.

By the way, this is my first post and just found this forum. This is really an amazing site and totally impressed by the inventiveness and openness to share information. If I had spare green laying around I would definitely have sent it off to Michael Bass as his worksmanship seems to be great and he made these mods to help his son which scores big points.

Thanks xoshooter!

The 580 is pretty easy to do, once you have done a bunch...the other units just take some time and care to get it right.

Like anything else, experience helps...you don't see my creative pictures posted...just my take aparts, and fix-its and new things I am making on my site.

Kudos to all of you folks for the great pictures being posted, keep up the great work!

Michael
www.MichaelBassDesigns​.com