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05-04-2015, 03:58 PM   #1
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Troubles with 645d and 135LS sync

Hey all - first time post'er here. I've tried to research this subject to no avail so I am hoping someone can help.

I've got the 135 LS lens on my 645d - hooked up with the LS hot shoe adapter. I'm in Manual mode, the lens is set to 1/60, the lens is cocked and I go to take the shot ... and this is what happens: The leaf shutter does it's thing and then the flash goes off ... far too late. 1/60 is the slowest I can go but do note that I have tried all shutter speeds on the LS lens with the same results. The result is a bunch of unexposed images, eating up my shutter count!

The lens seems to be triggering the flash through the cable, but all is happening after the shutter has released. Can't seem to find anything in the menus that is the golden ticket to what I am doing wrong. Any thoughts out there?

To clarify - the camera settings are Manual Mode, ISO 100 - 1600 (tried them all just to see if I was getting ANY exposure), tried all stops from F/4 - on up.

Note - I AM using a canon 430 EX II which triggers just fine when not using the leaf shutter, all the way up to 1/125 as it should.

Any insight would be welcome!


05-10-2015, 11:49 PM   #2
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You are syncing the flash off the PC connector on the lens, not the camera body, I'm assuming (not that clear to me from yr post)?
05-12-2015, 08:09 AM   #3
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Yes, thank you for the reply. The LS cable is connected to the LS lens, not to the camera. This should be the proper way to connect the cable as I would understand it. Still not able to get sync.
05-12-2015, 08:14 AM   #4
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I've used the 135mm LS & 645z a few times. Had problems initially as the 135 hadn't been used for years when I got it about 9months back. It came right after repeated activations.

I used it for a portrait shoot last week again and about 1 of 10 frames were very overexposed. I'm suspecting the lens shutter is perhaps becoming sticky?

See what happens if you try repeatedly. It may free up like mine?

05-12-2015, 10:49 PM   #5
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The 135 LS, when cocked, sets the focal plane shutter on a 645 to 1/8 sec. This may not happen on the 645Z. You may need to manually set the shutter speed to 1/8 sec. If the shutter speed of the focal plane shutter is not 1/8 sec. the focal plane shutter will block light from getting to the film.
06-19-2015, 07:59 AM   #6
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Hans, my 645D and 135LS is doing the same, flashing too late. Did you ever find the cause?
06-27-2015, 07:40 PM   #7
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I not sure if i'm understanding your problem, from the way you are stating it but, I feel the need to reply. with my 645d I mount the flash unit on a straight or l shaped bracket. them I connect the pc cable to the lens, I then set the speed on the lens and cock it and shoot. I take the hot shoe out of the equation.
06-28-2015, 07:50 AM   #8
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Had this problem with a Sigma flash. Changed to Metz and everything was OK. Was it flash on first or rear curtain - I did no further investigations.


07-25-2015, 03:03 PM   #9
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Bull, yes this is the exact way I have it set up, and have used multiple flash units, each one syncs but syncs too late so the frame is black.
07-25-2015, 03:27 PM   #10
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QuoteOriginally posted by KGH Quote
Bull, yes this is the exact way I have it set up, and have used multiple flash units, each one syncs but syncs too late so the frame is black.
Your shutter speed on your 645N/D/Z camera needs to be set to 1/8 of a second or it will not sync with the LS lens.


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