why my R2a can't sync with stuido flash??? WHY??

[ivzhao]

i tired to use my newly purchersed R2a to shoot some studio shots, but it didnt work. i tried plugin the cable into the Synchro Contact(the one on the side), and i also tried plug in the cable into the hot shoe(is it what it called? the one on the top) with a convertor, but neither worked?

i am confused? why? and can somebody explain me what TTL is?

thank you very much.

 

[bmattock]

Do you mean that the flash did not go off, or that you did not get proper exposure?

TTL means through-the-lens. When applied to flash, it means that the camera directly controls the flash unit and can 'quench' or turn the flash off in milliseconds when enough light has been applied for proper exposure.

The Bessa cameras do NOT offer any form of TTL flash that I am aware of. Cameras that do have more than one 'contact' on the hotshoe. If you just see one big round contact in the center of the hotshoe, then there is no flash TTL as far as I know.

If your camera has no TTL flash capability, you have to use a flash meter to trigger your strobes and measure the resulting light output, and then set your camera accordingly for proper exposure. If you move or reset the power output of your lights, you must again measure your light with a flash meter.

This is not a problem for Bessas, it is a problem for ALL cameras that do not offer some form of flash TTL (and the matching flash units that can take advantage of that).

On the other hand, if your flash just did not go off at all, you may have a mechanical problem of some kind.

Best Regards,

Bill Mattocks

 

[jlw]

i tired to use my newly purchersed R2a to shoot some studio shots, but it didnt work. i tried plugin the cable into the Synchro Contact(the one on the side), and i also tried plug in the cable into the hot shoe(is it what it called? the one on the top) with a convertor, but neither worked?

Don't worry, there's nothing wrong with your camera or studio flash unit!

The reason your studio flash didn't work is that the flash sync circuit on an R2a (or R3a) is polarized. That means the flash's trigger current will flow through it in one direction, but not the other.

Old cameras didn't have this problem because their sync circuits used a mechanical switch. Many modern electronic cameras use a transistor instead -- faster-responding and more reliable, but it does introduce this polarity problem.

Easy fix: If your studio flash unit uses a sync cord that plugs into the power pack via an "H" prong connector (common on American-made flash gear; looks like a regular household plug) then just turn the connector over and plug it back in. This will reverse the polarity of the sync circuit.

Harder fix: If your studio flash unit uses a sync cord with a coaxial plug (common on European flash gear) then you'll either have to order a "sync reverser" from the flash manufacturer, or snip the cable and switch the two wires inside to reverse the polarity.

Alternate solution: Buy a "sync isolator" such as the Wein Safe-Sync. This uses its own switching circuit to isolate the camera's sync contacts from the flash circuit, and should enable your flash to work without regard for polarity.

Another alternate solution: Put a very weak hot-shoe flash in the camera's hot shoe and use a slave-eye unit on the studio flash to fire it.


People don't normally have this problem with hot-shoe flashes because the polarity of these is fairly standardized. With studio flash gear, though, there's no dominant standard, and there's no dominant standard for cameras, either. When I ran into this problem myself (with my R3a and Epson R-D 1) I found that both the Voigtlander and Epson require one polarity, and my Nikon D-100 requires the opposite polarity. So, I've had to mark my power packs with which way the H plug needs to face for each camera, and have wired up two different sync cables for the portable unit I use that has a coaxial sync connector.

 

[bmattock]

Don't worry, there's nothing wrong with your camera or studio flash unit!

The reason your studio flash didn't work is that the flash sync circuit on an R2a (or R3a) is polarized. That means the flash's trigger current will flow through it in one direction, but not the other.

Now that's interesting. I have never run into that, and had no idea. But then again, I have no older studio gear, it's all cheap but fairly modern. I'll keep that in mind in case I have a problem someday. Thanks!

Best Regards,

Bill Mattocks

 

[ivzhao]

Don't worry, there's nothing wrong with your camera or studio flash unit!

The reason your studio flash didn't work is that the flash sync circuit on an R2a (or R3a) is polarized. That means the flash's trigger current will flow through it in one direction, but not the other.

Old cameras didn't have this problem because their sync circuits used a mechanical switch. Many modern electronic cameras use a transistor instead -- faster-responding and more reliable, but it does introduce this polarity problem.

Easy fix: If your studio flash unit uses a sync cord that plugs into the power pack via an "H" prong connector (common on American-made flash gear; looks like a regular household plug) then just turn the connector over and plug it back in. This will reverse the polarity of the sync circuit.

Harder fix: If your studio flash unit uses a sync cord with a coaxial plug (common on European flash gear) then you'll either have to order a "sync reverser" from the flash manufacturer, or snip the cable and switch the two wires inside to reverse the polarity.

Alternate solution: Buy a "sync isolator" such as the Wein Safe-Sync. This uses its own switching circuit to isolate the camera's sync contacts from the flash circuit, and should enable your flash to work without regard for polarity.

Another alternate solution: Put a very weak hot-shoe flash in the camera's hot shoe and use a slave-eye unit on the studio flash to fire it.


People don't normally have this problem with hot-shoe flashes because the polarity of these is fairly standardized. With studio flash gear, though, there's no dominant standard, and there's no dominant standard for cameras, either. When I ran into this problem myself (with my R3a and Epson R-D 1) I found that both the Voigtlander and Epson require one polarity, and my Nikon D-100 requires the opposite polarity. So, I've had to mark my power packs with which way the H plug needs to face for each camera, and have wired up two different sync cables for the portable unit I use that has a coaxial sync connector.

thank you very much sir. thank your for spending your time writing such a long paragraph. have a good new year.

 

[jlw]

You're welcome. Did you get your flash unit to work? If you still have problems next time you try it, let us know.