Odd issue with Bronica lenses + Sunpak flash

Good day gentlemen

Hope someone might have some experience with this. I am returning to Film / MF after (way too many) years in digital photography. I lost a lot of my old MF equipment but could never part with my "main hardware" - basically all Bronica SQ stuff. Recently a friend and judge at a local photography club gave me a Sunpak Auto 144 flash ("You seem to dote on old stuff - here's a flash for ya!") which I gratefully accepted. So.... I did some "eyeball" testing first to make sure it actually works and syncs with my gear but immediately noticed that the flash seems to fire too fast - the shutter is only about 80% - 90% open when the flash fires.

I tested this with 3 different camera bodies (2 X SQ-A + 1 X SQ-Ai, one of the SQ-A bodies is virtually brand new) and 3 different lenses (All Zenzanon S lenses, 40mm / 80mm / 200mm). I would have assumed that this must be due to the gear's age / stored away in my Man cave too long etc but exactly the same issue with what amounts to 3 different cameras?? The Bronica S and PS lens shutters (Seiko) are triggered by an electronic timer unit in the camera body... The actual speed accuracy for all 3 lenses seem 100% good though, and batteries (driving the timer unit itself) are fresh etc. I used to use a Metz flash back in the 1990s and never had an issue like this - it would have caused some vignetting that I absolutely would have noticed. Sadly I no longer have the Metz so I cannot do a comparative test. I can also say the the sync'ing for the Sunpak is 100% perfect on a Pentax ME Super body, there is a rumour that old flash units may cause damage to the electronics on a DSLR so I didn't test on any DSLR bodies.

Any ideas? Is this simply an X/FP timing issue, and if so, what flash units are available today that would still work?

Opinions and advice welcome and thank you in advance!

Welcome to APUG from a near neighbour.

Do the lenses offer a choice of synch (M and X)? If so, check the switch.

Also, with the leaf shutters, you wouldn't see vignetting in the negative. You would just see a change in exposure, because the flash is triggered when the aperture isn't fully open.

MattKing said:

Do the lenses offer a choice of synch (M and X)? If so, check the switch.

Click to expand...

Hi Matt

Thank you - Good question, I actually had to go back and check the manual! According to the instructions all Zenzanon-S lenses are sync'ed for X - all the way up to 1/500. This is quite strange, and I am beginning to wonder if this was always an issue... Seeing as you would never notice this if the lens is stopped down somewhat (meaning, it only becomes apparent at full aperture ONLY - F2.8 for the 80mm lens, F4 for the 40mm lens etc. Still, it is a rather disconcerting / upsetting discovery for me! It also seem to imply that ALL lens-shutter Bronicas must have this issue, or at least with certain flash unit brands.

I wonder if any other Bronica (SQ / ETR series) users have noticed the same?

-- JN

If you are relying on your eye to determine the timing, most likely you are coming to an incorrect conclusion.

If you clearly see the flash through the opening and closing shutter, the synch is probably correct. An 80 - 90% open shutter will transmit almost all of the light that a fully open shutter will, and most likely what you are seeing is the shutter going through mostly open to fully open through slightly closed during the very short period of time that comes close to coinciding with the triggering of the flash. The flash and the shutter are generally faster than your eye is.

There is one other possibility though. The lens aperture (iris diaphram) may be sticky - it may not be opening fully when you release the shutter.

You can check to see if the exposure is being affected with some trial exposures, but I'd be willing to bet that unless you have a slow aperture you won't see a problem.

Welcome to APUG

When using a strobe with lens [leaf] shutters, one should use X synchronization. For strobes with focal plane shutters, there should be a shutter speed or range of shutter speeds recommended by the camera manufacturer. That speed or range of speeds are those when the shutter is completely open during a slightly delayed flash.

Leaf shutters trip and electronic flash when they're fully open, just as focal plane shutters do. With a mechanical
shutter there's a small chance that the sync switch is slightly bent. Never seen it but know the closing of the
switch will do this*
If it's an electronic switch this obviously doesn't aapply.

If you look through the lens do the blades intrude from the edges? Some lenses never fully open, even on B.
If they don't, it's a normal thingy.

*playing with shutters to see what happens when the synch switch is messed with

Thank you all for the suggestions and advice (and not to mention the warm welcomes). I'm going to accept that it is normal behaviour - after all, 3 different body / lens combinations all act exactly the same way. I should not be using the "eyeball" method of testing things like Shutter / Flash synchronization anyway.

Sirius Glass, your signature is quite brilliant ("...I leave digital work...") - I will have to quote it sometimes. Hope you don't mind.

-- SJ

Hi from Burnaby . I've a couple of old vivitar 283 flash units that I use with my ETRsi. They've worked
well for me , if you'd like to try one , just pm me and we'll see what we can arrange . Peter

The SQAi and the ETRSi have TTL flash, Sunpak makes a dedicated module for the Bronica cameras. Still all these cameras use brilliant electronic shutters controlled by the camera body, you should be able to sync at any shutter speed 500th on down. even without TTL. I'm down to 3 SQAi bodies. Love them.
Best Mike

I believe you mean ttl capabilities . With the ETR(si) series they required the SCA something or another adapter
to perform through the lens metering . Not trying to get picky , just in case others might think it's a built in feature . Regards, Peter

When I test large format leaf shutters for correct flash sync I point the shutter at a light colored wall in a low light room and look at the rear of the shutter with the flash pointed at the wall. In sync on X I will see shutter blade edges in the outer edge of the shutter opening to no shutter blades at all, M sync will show the shutter blades just opening as the light from the flash falls off. Testing is done with the aperture wide open. If the shutter blades protrude more than 1/2 stop into the shutter opening I adjust the mechanics of the shutter flash sync. On an electronic controlled shutter there should be an adjustment somewhere inside the camera. From what you describe I would not attempt to adjust any body or lens at this time.

Sixbysixjan said:

there is a rumour that old flash units may cause damage to the electronics on a DSLR so I didn't test on any DSLR bodies.

Click to expand...

Vintage electronic flash, from introduction through the 1960's, may put as much as 455V to the flash sync contacts. I do not know when the design changed but later flash units blocked the high voltage needed to trigger the flash tube from the trigger contacts. A general rule of thumb is if the flash operates on 4 AA cells then it is likely safe for all types of cameras. If in doubt use an flash adapter/isolater such as
https://www.bhphotovideo.com/c/product/245292-REG/Wein_W990560_Safe_Sync_Hot_Shoe_to.html

moto-uno said:

Hi from Burnaby . I've a couple of old vivitar 283 flash units that I use with my ETRsi. They've worked
well for me , if you'd like to try one , just pm me and we'll see what we can arrange . Peter

Click to expand...

Hi Peter

Thank you for the kind offer. Based on what Shutterfinger posted it sounds like it is perfectly fine (no shutter blades at all visible at one F-stop down from max aperture, and only visible at outer edge at max. aperture). I'm going to have to buy a "real" flash unit sooner or later anyway and interestingly enough I was looking at V.283 units on Amazon.com a week or so ago, but was unsure if those are suitable. From what you are saying those should work fine for me then.

This site has a fair bit on it about electronic flash trigger voltages: http://www.botzilla.com/photo/strobeVolts.html

The Vivitar 283 was quite the workhorse and powerful enough for many situations , another bonus is that if
the plastic mount should prove "ïffy" there's an aluminum replacement available for it . Peter

I just conducted a test with a Bronica ETRSi, no battery inside so shutter defaulted to 1/500, connected to a Metz flash via the PC synch socket. I shot two tests, one with f/11 on the lens and the other with the f/3.5 lens (wide open).

To shoot the ETRSi, I mounted a digital camera set at ISO 100 on a tripod in a room with very low level ambient illumination, with Metz flash aimed in Auto mode (ISO 100 at f/16) at the ETRSi. The digital camera was set to trigger its shutter delayed 10 sec. after I pressed its shutter release, and its shutter was set to stay open 5 seconds, with its lens at f/16.

Procedurally, I would press the shutter release on the digital camera, and when it opened its shutter I would immediately trigger the ETRSi to open its shutter, triggering the flash to fire. The Metz flash was positioned at the digital camera to illuminate the ETRSi and the PE lens shutter/aperture. Here are the results, with lens wide open and with lens at f/11.




The f/11 shot was to show the aperture position within the lens (apologies for the dust on the filter!), while the f/3.5 shot was to show if any portion of the shutter blades were at all visible due to some latency between shutter action and the triggering of the flash. I see no evidence of shutter blades in the first shot.

wiltw said:

...Here are the results, with lens wide open and with lens at f/11.... ...show the aperture position within the lens (apologies for the dust on the filter!), while the f/3.5 shot was to show if any portion of the shutter blades were at all visible due to some latency between shutter action and the triggering of the flash. I see no evidence of shutter blades in the first shot.

Click to expand...

Hi Wiltw

Thank you for the information. In the meantime, I have acquired a NOS ("New Old Stock") 80mm PS lens from an eBay seller in Japan. The lens came in its original packaging including a carry case, and showed no signs of ever been mounted on a camera - as far as I can tell, the seller was being honest. Very interestingly this lens seems to be perfectly synchronized with my flash unit and shows no sign of shutter blades being visible at any shutter speed or aperture at all when the flash is firing. I am still subscribing to Shutterfinger's opinion - that my S lenses are perfectly fine and within acceptable operational parameters. I am not sure but perhaps the specific shutter model from Seiko changed between the S and PS series lenses (probably likely so), so it may be a characteristic of the specific Seiko shutter model being used on the S series.

And as the ultimate n final test.. shoot a roll of film?