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Old Aug 11, 2007, 7:40 AM   #1
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I'm wanting to learn about exactly how hotshoes work.

What is the purpose of each pin on the hotshoe ?

I understand that each camera might have a slightly
different hotshoe layout of the pins and their purpose
might be different.

I also have read that there's a standard hotshoe layout
of the pins and their purpose is set by and ISO standard.

As much as I've looked around Google I can't find information on:

1. What does each pin do on a standard hotshoe ?
2. What are the electrical signals on each hotshoe?
3. If there are variations among cameras is that
information readily available somewhere?

My cameras now are a Oly C750 and an Oly C2000

Thanks for any help. If I couldnt' find the information
easily I guess people don't need it. But I make my own
devices and circuits occasionally.
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Old Aug 11, 2007, 11:17 AM   #2
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The ISO standard only defines the larger center pin in the hotshoe socket... all other smaller pins are up for grabs!
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Old Aug 11, 2007, 9:23 PM   #3
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Some cameras have a PC sync socket, also called X-sync, Which is just a switch controlled by the shutter. This makes using an external flash simpler, and is also used to control studio type strobes. As a rule, the center pin of the hotshoe is the same or similar.

Minolta cameras and their succcesors ( Sony) use a hotshoe which does not conform to ISO ( no center pin), but most others do.

The extra pins are used to communicate focal distance and/or exposure levels. I believe some cameras can also control flash time based on P-ttl or ttl exposure information. High-speed flash sync, trailing curtain flash, and other effects are available using dedicated flashes. Non- OEM flash makers have been able to determine how the info is passed, and have made units which work similar to the mfg flashes.

brian
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Old Sep 15, 2007, 7:09 AM   #4
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Here's a few links, but no Olympus stuff. Gives you an idea of the sort of things that go on though.........
http://81.216.246.116/e/ettl/
http://snowcat.de/flashcontroller/

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Old Oct 3, 2007, 11:36 PM   #5
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SteveB wrote:
Quote:
Here's a few links, but no Olympus stuff.* Gives you an idea of the sort of things that go on though.........
http://81.216.246.116/e/ettl/
http://snowcat.de/flashcontroller/
Thank you.

Great posts.
The ones with urls were especially helpful as the terminology gave me some more searching
tips.

Andre
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Old Oct 7, 2007, 12:02 PM   #6
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AndreLikesPhotos wrote:
Quote:
SteveB wrote:
Quote:
Here's a few links, but no Olympus stuff. Gives you an idea of the sort of things that go on though.........
http://81.216.246.116/e/ettl/
http://snowcat.de/flashcontroller/
Thank you.

Great posts.
The ones with urls were especially helpful as the terminology gave me some more searching
tips.

Andre
I also have a C-750 and I wish I could get any cheep flash to work on the hot shoe. So far I have tried 4 flashes and the camera will not trigger any thing through the center pin.

I would rather have an off camera flash most of the time and I found this adaptor for the hot shoe that should let you use any old flash in non TTL with the OLY. The only problem is the cost of $60.00. Still that better than $250 for a F50.

http://cgi.ebay.com/Olympus-Safe-Syn...QQcmdZViewItem

I still don't know if I would rather use my old C-750 which can take some great pictures some times or just get a new S5 with a hot shoe.



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Old Oct 9, 2007, 2:08 PM   #7
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It appears that the item is made by Wein.. or it's a Chinese knock off.

Wein is well known for their slave products. It would be helpful if you did some research and maybe visited a large camera store to see what they have similar to the Wein unit for the Oly C750.

If I had time I'd have done it before I posted but all I did was find out that the Wein seems to be popular and available all over.

Good luck. I'll check back and try to contribute more.
PS. It appears that Wein literature said they put 6 volts into the camera. I wonder if the center pin shorts to ground during a flash. Thus 6 volts from the Wein would be shorted to ground and this would tell the Wein to flash.

I'm pretty dumb at this point.
Let's find out how it works.

Andre
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Old Oct 29, 2007, 2:33 AM   #8
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Safe sync`s are very simple to make, 1 PNP transistor , 3 resistors , 1 capacitor and a 400v thyristor. power source is a battery 3 - 6v . The N----- in the woodpile is the male and female parts for using on a hotshoe. An old clapped out flash gun can be broken down and the base used.
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Old Nov 3, 2007, 2:50 PM   #9
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I used a Nissin 360TW auto thyristor flash for a couple of years on my Oly C750 before moving it to my Pentax K100D. They're very old so should be dirt cheap if you can find one. It's got a low enough trigger voltage (10v) not to case any problems and has an extra fill-in flash with a manual on/off switch, and does swivel and tilt. It gives very consistent exposures with the flash in Auto mode and the camera in manual mode.
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