# Using old (film) flash units with DSLRs?



## iolair (Nov 5, 2009)

I'm awaiting my eBay Canon 20D, and wondering if it's possible to save a lot of money by using older flash units with it - units from film cameras.  There are plenty around!

I'd want to use the flashes (at least two, which might be different), with some kind of cheap remote control kit, with the flashes off-camera on stands.  Is this technically possible?  Am I right in saying that a flash hotshoe, for basic connections, is universal?  How far does the connection date back?


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## cliffy13 (Nov 5, 2009)

I think you will find this site gives you all the help you need

Photo Strobe Trigger Voltages


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## robertwsimpson (Nov 5, 2009)

I use a c.1979-1980  flash unit with my XTi without issue.  The cool thing is that it doesn't really know there is a flash, so I can use up to a 1/350 shutter speed


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## PatrickHMS (Nov 5, 2009)

It is okay to use any of them off-camera, off the DSLR hot shoe - but be very careful what you choose to use ON the hot shoe of your DSLR.

All your DSLR is, is a computer with a lens, and using a flash (even once) with excessive trigger voltages can damage circuits inside the camera.


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## iolair (Nov 5, 2009)

OK, so using it with a wireless remote control, any flash with a hotshoe connection will be fine?  Great


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## Big Mike (Nov 5, 2009)

Hot shoes are pretty universal.  Sony/Minolta is a little different though.  

The link above gives reported voltages for many flash units.  But keep in mind that their save/not safe rating is for older (film) canon SLR cameras that were only rated for 6 volts.  The Canon 20D is rated for 250 volts...so just about any flash should be save to use.  

When using a radio remote trigger, you don't need to worry about the camera, but the remote receiver.  I've never heard of anyone having a problem with trigger voltage on a remote though.  

So yes, you can pretty much get any flash to use as an off-camera remote flash.  I would suggest only getting flashes that have manual power adjustments though.  I've got a box full of old flash units...some of them are great for this...others, while usable, are just not as convenient.


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## iolair (Nov 5, 2009)

Thanks Mike,

It's only the PC-Sync connection on the 20D that can cope with 250 volts though.  The hot shoe connection is limited to 6 V.  (This according to the 20D manual downloaded from Canon's site).

I don't know how many flash units have the PC-Sync type connection on.

Don't all off-camera flashes have manual power adjustment ;-) (1-stop reduction?  Pick up the flash and move it 40% further away.  2-stops?  Pick up the flash and move it twice as far away).


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## Big Mike (Nov 5, 2009)

It's the same circuit, as far as I know.

I'll have to read up on that.


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## Big Mike (Nov 5, 2009)

On page 98 is says



> *Also, do not connect to the camera's PC terminal any flash unit requiring 250 V or more
> 
> *Do not attach a high-voltage flash unit on the camera's hot shoe. It might not work


No mention of 6 volts there, and I can't find any other mention of flash trigger voltage.


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## fokker (Nov 5, 2009)

If you go for something like a canon 540EZ they have all the bits you need for proper off-camera flash usage like manual power adjustment (up to 1/128) and zoom head. You can pick up dirt cheap usually just because they aren't E-TTL compatible.


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## iolair (Nov 5, 2009)

Big Mike said:


> On page 98 is says
> 
> 
> 
> ...


Ooops, you're right... I guess I read the 6V hotshoe limit somewhere else.
(e.g. here -> Flash Photography with Canon EOS Cameras - Part II. )

Though as I said previously I want to use the flashes remotely, so they'd be with some breed of reciever anyway and not physically connected to the camera.  It sounds like I'm home and free for that


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## Big Mike (Nov 5, 2009)

> Ooops, you're right... I guess I read the 6V hotshoe limit somewhere else.
> (e.g. here -> Flash Photography with Canon EOS Cameras - Part II. )


They are talking about EOS film cameras.



> Though as I said previously I want to use the flashes remotely, so they'd be with some breed of reciever anyway and not physically connected to the camera. It sounds like I'm home and free for that


Absolutely right


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## archp2012 (Feb 7, 2012)

On the unlikely chance of resurrecting a 3 year old thread, I'd like to ask if the OP or anyone else has had any success using old flashes as remotes with new DSLR's.


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## KmH (Feb 7, 2012)

Yes. By using RF triggers.

Is today National Dig Up Old Dead Thread day?


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## greybeard (Feb 7, 2012)

I use a Nikon SB28 with my d5100.  It works on automatic settings but not TTL.  It all has to do with the trigger voltage.  Some older flashes have a high trigger voltage that will fry the electronics in a DSLR.  Make sure the one you are wanting to use has a safe trigger voltage for your camera.


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## MLeeK (Feb 7, 2012)

I have flashes that are not even canon compatible that I use off camera. If you are ever in doubt of the voltage of an older flash just don't mount it on your camera. As for off camera and trigger setups-you can use any flash unit! It's a great way to amass a large collection of small flashes for super cheap!


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