Minolta x700 flash sync issue

Started 6 months ago | Discussions
black_caniche New Member • Posts: 11
Minolta x700 flash sync issue

Hi all,

Pulled my old (bough new by my dad) Minolta X700 out of storage as I'm getting back into film.  While all works as it did last time I used it, I noticed that my flash is not syncing correctly (i.e. partially exposed frame).  I've used this thing for years with a Motor Drive + Metz 60 CT-1 and never had an issue.  Tested it with 3 different flashes including a Metz M400, and a Metz 45 CT-5, and have the issue for all.  Non-flash is OK, no issue.   Shooting at 1/60 as always.  I'm a bit confused.  Could exposure speed shift with time-age? If that were the case, this looks like the camera is shooting too fast for the flash (i.e. faster than 1/60).

These things had a bad rep for capacitor issues, but if I understand correctly, that would kill the shutter completely.  I did check mine and it looks like new (no leaks, nothing) and the shutter sounds like it always did.

Any ideas?

Thanks.

OP black_caniche New Member • Posts: 11
Re: Minolta x700 flash sync issue

Hi again,

I added a contact sheet sample of the issue.

As you can see, all images (shot at 1/60 with X-sync Metz 45-CT5 - using non dedicated sync cord) have an underexposed portion on the left). Not sure how to interpret this: like if the flash did not cover the entire exposure (left means that tail-end of exposure missed).... like if the second curtain was closing too soon if that makes sense.. I'm confused

Below, no-flash shots on same roll:

sybersitizen Forum Pro • Posts: 23,941
Re: Minolta x700 flash sync issue

black_caniche wrote:

Could exposure speed shift with time-age?

Yep. Speed and/or timing can drift.

Any ideas?

The shutter curtains in the X-700 move from right to left, seen from the back. Since the image at the film plane is reversed left/right and top/bottom, the obstruction must be on the right side as seen from the back, meaning the second curtain is starting to close too soon, or the flash 'fire' signal is sent too late. It seems a bit odd that an electronically controlled shutter would drift that much, but the evidence is pretty clear.

Maybe try speeds slower than 1/60s next time, though the curtain might still close too soon.

FrancoD Forum Pro • Posts: 19,036
Re: Minolta x700 flash sync issue

Try this to see if using another shutter speed will work.

Take the lens off . Conned the flash and put the flash head against the mount

Open the back and put a piece of white paper (folded in two ) against the shutter. Have the shutter speed on 1/60 and fire the shutter. You should see the same problem as you see on your negs. Change the shutter speed and see when you get a full sync.

This is if you want to avoid sending the camera in for repair.

(BTW, I found this comment from someone that had your same problem :

Drack wrote:So today I took the camera to the local repairman and can you believe it , it got fixed in 5 min . The whole repair costed me 8 USD . I`m very pleased with that and now I can try out a whole new system

Excellent news! What did he do?

He took off the bottom plate of the camera. Then he unscrewed one screw that was directly below the film take up spool. If I understood everything correctly that screw held in position 2 gearwheel`s that are responsible for cocking the curtains. So he simply turned them into their right position, screwed back the screw and the bottom plate and Ta daaaa.... The camera is as good as new"

OP black_caniche New Member • Posts: 11
Re: Minolta x700 flash sync issue

Thanks for the comments... so I'm not loosing it... the second curtain is (could be) off.  Will do the paper test to see if I notice any change.  If that (quoted) repair is for the same issue and that it's simply a mater of a mechanical (or could be a potentiometer) adjustment, that would be great.  No intention of sending it in for repair... not worth it.  The strange part is that I did not notice effects in non-flash situations; but then again, they might be much harder to notice... but still there.  DJT.

momotus Regular Member • Posts: 484
Re: Minolta x700 flash sync issue

black_caniche wrote:

Thanks for the comments... so I'm not loosing it... the second curtain is (could be) off. Will do the paper test to see if I notice any change. If that (quoted) repair is for the same issue and that it's simply a mater of a mechanical (or could be a potentiometer) adjustment, that would be great. No intention of sending it in for repair... not worth it. The strange part is that I did not notice effects in non-flash situations; but then again, they might be much harder to notice... but still there. DJT.

It may be that the flash sync timing is late, rather than the shutter rear curtain being off. That would allow available light photos to be perfect, but flash to be cut off, like your images. With a focal plane shutter, the flash sync timing is supposed to be delayed enough for the front curtain to be fully open, but the rear curtain has not yet started to close. So, if the sync timing is late...

It would be fairly difficult to diagnose without a shutter speed tester which includes sync timing.  If you are not going to fix it, it is all somewhat academic, I suppose.

OP black_caniche New Member • Posts: 11
Re: Minolta x700 flash sync issue

Well, I just did the paper test with the flash in front of the camera.  I was surprised at how clear the issue is with this test.  Here are my results (non scientific):

- @  1/125 it will exposed approximately 50% of the frame (ok, sounds normal)

- @ 1/30 it will expose the full frame (OK again)

-@ 1/60 it exposes approx 90% of the frame.  There is maybe at most, 2mm missing on the right (looking at the camera from the rear). Looks a lot worse on the picture.

Based on the posting referenced and the very basic description of the fix, I took the bottom plate off.  I removed the metal wheel located bellow the take up spool which is used to couple the motor drive (1 offset screw holds it in place).  Other than that, there is another wheel that turns when cocking the camera and has a few levers and stop levers (i.e. it don<t come out easy).  On that wheel there is a small adjustment screw (offset screw) with a drop of locktite.  I played with that and re-tested = no effect.  (or maybe I really screwed something up now).

Anyhow, I have the service manual, but it's of not help.  The section that refers to 1st and 2nd curtain adjustment (p119) describes what seems to be a very primitive procedure that seems to need to be done with the curtain assembly out of the camera.  Either I'm an idiot, or there is no obvious way to access both sync wheels (as described in the manual and the post) from the bottom.  Oh, and I can't seem to match any of the parts in the manual diagrams with those that are exposed from under the camera.

I doubt I could find a camera repairman as efficient as that of the poster around here

From what I got from the manual, two gears on top of each other are responsible for the sync of both curtains.  To adjust them, you need to lift one off the other and reposition (yes, very precise indeed).  No fancy set screw or anything of that nature.

(see pic before removing that motor coupling wheel - forgot to take one after sorry)

Horiz Opposed
Horiz Opposed Contributing Member • Posts: 604
Re: Minolta x700 flash sync issue

I would just shoot at 1/30. The flash will freeze anything it hits, the ambient might get a bit soft, but if you aim to hold the camera steady during exposure I think it will be fine.

As others have said, clearly there is a problem with flash synchronization.

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Ross

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