Mamiya 7ii metering problem

[spatz]

I have a Mamiya 7ii with the 65mm lens and I am having a weird issue with it which I'm not sure if its due to me doing something wrong or a genuine fault with the camera. The camera works fine in 99% of situations except that when i focus at 2m or so or closer the recommended shutter speed in the viewfinder jumps suddenly to the right pointing overexposure arrow and when the lens is focussed closer than 2m it wont show the recommended shutter speed anymore but will do so again when i focus further then 2m. Its a bit of a weird one but I am wondering if anyone else has had a problem like this? Ive check the contacts and they seem fine. The shutter speeds and aperture are still accurate based on neg density/scans but it has this weirs quirk which has me really scratching my chin! Any help or advice is appreciated

 

[moto-uno]

I'm not sure if it's this forum or the RFF ,(I believe there's a thread regarding this issue) but
the 65mm lens seems to have an occasional problem with the internal wiring (cable ?) that could explain this .
As the lens is extended the wiring may be getting pulled from it's contacts . I can't recall if it's a cheap repair or not .
Cheers Peter

 

[shutterlight]

As with all things 7-related, I would contact Bob at Precision Camera Works in Illinois to ask about that.

 

[spatz]

Thanks for the advice so far. I've contact Bob and my local camera service centre which has serviced all my gear so far and see what they say. I imagine its related to the wiring on the 65mm lens but I'll confirm here later once it's been repaired.

 

[kpoz]

Thanks for the advice so far. I've contact Bob and my local camera service centre which has serviced all my gear so far and see what they say. I imagine its related to the wiring on the 65mm lens but I'll confirm here later once it's been repaired.

Did it turn out to be the wiring in the lens? My 65mm developed this problem out of the blue last week. There’s no issue if I focus from 7m to infinity, but anything closer and I get an overexposure warning from the meter.

 

[Mamiya_Repair]

Did it turn out to be the wiring in the lens? My 65mm developed this problem out of the blue last week. There’s no issue if I focus from 7m to infinity, but anything closer and I get an overexposure warning from the meter.

This issue is caused by a broken flex cable that transmits aperture info from the shutter to the pins on the rear of the lens. Very common on the 65mm.

 

[Steve Goldstein]

Does this problem affect only the metering? In other words, if I set aperture and shutter speed per a handheld meter or sunny-16 will I get the exposure I expect? I'm thinking ahead to the day when my 65mm may develop this issue.

Is there any way to repair this? Or is it "repair is by replacement" as they often say in auto repair manuals?

 

[Mamiya_Repair]

Does this problem affect only the metering? In other words, if I set aperture and shutter speed per a handheld meter or sunny-16 will I get the exposure I expect? I'm thinking ahead to the day when my 65mm may develop this issue.

Is there any way to repair this? Or is it "repair is by replacement" as they often say in auto repair manuals?

The flex cable carries information on the aperture setting but also allows shutter release signals to communicate with the lens. However, in just about every case I have seen, only the aperture trace is damaged so the lens would still work fine other than the meter not working. Solution is to replace the flex cable.

 

[spatz]

Yes all the above info is correct. Bob @ PCW CLA'd my 7ii and fixed the 65mm back in 2017 for 520usd not incl. return shipping. Goodluck with getting it fixed. Certainly worth having it working 100% and have the rangefinder calibrated etc. while you're at it.

 

[Steve Goldstein]

That's not an inexpensive repair! I wonder if there's any way of reinforcing a working flex to extend its life. The challenge would be to (a) prevent the reinforcement from interfering with operation and (b) prevent the reinforcement from introducing a new stress point of its own.

 

[Ben 4]

That's not an inexpensive repair! I wonder if there's any way of reinforcing a working flex to extend its life. The challenge would be to (a) prevent the reinforcement from interfering with operation and (b) prevent the reinforcement from introducing a new stress point of its own.

Sounds like that sum included a camera CLA.

 

[spatz]

That's not an inexpensive repair! I wonder if there's any way of reinforcing a working flex to extend its life. The challenge would be to (a) prevent the reinforcement from interfering with operation and (b) prevent the reinforcement from introducing a new stress point of its own.

It was not cheap for sure but in my eyes very worth it. I've been using the same combo to this day without fault. I was lucky to have the lens repair covered by the person i bought it 2nd hand from (that part cost 260usd) and was happy to cover the rest for peace of mind. Bob replaced a switch or two as well and the rangefinder calibration holds true to this day.

In regards to reinforcing the flex cable, it's probably more trouble than it's worth. As a mechanic/technician myself, from my experience sticking with OEM/stock parts despite their own issues is the least problematic option overall.