Canon 7s Repair Recommendations?

[KoNickon]

I'd appreciate your recommendations for a repair and CLA. Mine has a shutter issue -- seems as though the wind lever mechanism has become detached from the shutter. You can wind the shutter by manually turning the wind sprocket, but that's obviously no good for actually using the camera.

The meter seems off by a stop or two.

But what seems almost the most vexing problem for me is that the RF patch seems out of focus -- almost as though I need a dioper adjustment to have a crisp image, but I'm not sure that's something that can be adjusted. Anyone else have this problem?

Essex Camera is a logical option for the work, but does anyone have other recommendations? Thanks.

[Robert Lai]

Clarence Gass repaired my Canon 7s.

It's finder is sharp, and I had him adjust the RF as well as the Canon 50 1.4 to be right on focus wide open. When I got it, the camera RF was way out.

The lens was focusing "beyond infinity". This can happen with the original Canon rear caps, as they are very shallow. If you try to focus the lens to infinity with the rear cap on, you can screw up the RF cam, which will hit it.

My shutter winding is smooth as butter, and the timing is accurate.

I don't believe that there are any potentiometers to adjust in the Canon 7s meter. However, I use the cris adapter with silver 1.5 cells, and the results are very accurate.

Gass Camera Repair
5604 Johnson Drive
Mission, KS 66202

Tel: 913-432-6057

Tuesday to Friday (closed Monday) 9 - 4:30 central time
Saturday 9- 12 Central.

Best to call and talk directly to Clarence first.

[Mackinaw]

If there's any knock against the 7 or 7s rangefinder patch, it's the "mushiness" associated with it. It's not as sharp and well-defined as a Leica M. A good cleaning of the viewfinder can help things a little bit, but just be sure to use a repair tech who knows what he's doing.

As for other repair techs, you might try Youxin Ye, though I'm not sure of he services the Canon 7. I think DAG services the 7.

Jim B.

[Dez]

Incorrect readings of the 7 or 7S meter, if they are consistent across the range, are because of incorrect meshing of the gears driving the meter readout. I am always surprised at how very often people neglect to set this correctly when reassembling the camera.

Take off the shutter speed dial. This is a bit tricky. Completely remove the grub screw between 1 and 1/2, and then rotate the dial until the screwheads of the other two are visible through the holes in the dial. Note the shutter speed. The other two screws only need to be loosened.

Lift off the ASA/DIN dial.

Pick any usual ASA speed. Turn the brass gear appearing at the left side of the hole where the shutter dial was until you get a correct reading for that ASA speed and shutter speed on the meter.This is best done when you have a large deflection on the dial.

The trick is to reengage the gear at the bottom of the ASA/DIN speed dial with the gear driving the meter in the correct position so that your chosen ASA speed shows through the aperture in the shutter dial when it is placed back in its correct position. This is rather fiddly, but with a bit of patience, you will get everything right. Put the removed long grub screw back in and tighten it. Then rotate the dial until the other two can also be accessed.

Cheers,
Dez

[KoNickon]

Interesting, and thanks. The thing is, I think the High range (low light) is off, but the Low range (daylight) is more or less accurate. But I'll experiment some more.

Originally Posted by Dez

Incorrect readings of the 7 or 7S meter, if they are consistent across the range, are because of incorrect meshing of the gears driving the meter readout. I am always surprised at how very often people neglect to set this correctly when reassembling the camera.

Take off the shutter speed dial. This is a bit tricky. Completely remove the grub screw between 1 and 1/2, and then rotate the dial until the screwheads of the other two are visible through the holes in the dial. Note the shutter speed. The other two screws only need to be loosened.

Lift off the ASA/DIN dial.

Pick any usual ASA speed. Turn the brass gear appearing at the left side of the hole where the shutter dial was until you get a correct reading for that ASA speed and shutter speed on the meter.This is best done when you have a large deflection on the dial.

The trick is to reengage the gear at the bottom of the ASA/DIN speed dial with the gear driving the meter in the correct position so that your chosen ASA speed shows through the aperture in the shutter dial when it is placed back in its correct position. This is rather fiddly, but with a bit of patience, you will get everything right. Put the removed long grub screw back in and tighten it. Then rotate the dial until the other two can also be accessed.

Cheers,
Dez

[Dez]

Well, having one range correct and the other not is reasonably common with the Canon 7 which changes ranges by adding a resistor, but the 7S switches ranges by rotating a mask in front of the CdS cell. If the cell's response remains linear, then fixing one range should fix both. Does someone out there have some info on the aging characteristics of CdS cells?

Cheers,
Dez

[Dez]

Make sure the mask is coming into place correctly when the ranges are switched. You can see the mask by looking carefully into the cell while changing the switch. I have seen a case where this got disconnected, and it sounds like your camera has had a tough life. It's worth putting work into it though. The Canon 7S is a desirable camera.

Cheers,
Dez

[Frontman]

The Canon 7 is an easy camera to work on. The winding issue might be caused by a piece of linkage combing loose, usually under the bottom cover of the camera. The viewfinder can become dim because there is an air gap between the lenses, you can clean between the gap if you remove the top cover. You can also clean the eye piece window, and a second eye piece window beneath the first one.

As for the meter, you must check that the shutter speed knob and meter gears are timed correctly. You do this by setting the ASA to 400, and then turning the shutter speed dial until it shows 1/15. With the meter off, the needle should indicate at the orange f/2.8. If something different shows, you will need to back out the three grub screws which hold on the shutter speed knob a few turns each (do not fully remove them, they are easily lost), and lift off the knob, you will see the brass gears beneath, turn the gear until the needle indicates the orange f/2.8, then reinstall the knob.

[KoNickon]

Thanks. So how to remove the rotary back release from the baseplate? Looks like I'd need a pin spanner to remove it from the film cavity -- but pretty darn hard to get at the holes.

Regarding the meter, when it's turned off, the needle is nowhere to be seen -- not anywhere near f2.8. This seems like the way it's supposed to be....

Originally Posted by Frontman

The Canon 7 is an easy camera to work on. The winding issue might be caused by a piece of linkage combing loose, usually under the bottom cover of the camera. The viewfinder can become dim because there is an air gap between the lenses, you can clean between the gap if you remove the top cover. You can also clean the eye piece window, and a second eye piece window beneath the first one.

As for the meter, you must check that the shutter speed knob and meter gears are timed correctly. You do this by setting the ASA to 400, and then turning the shutter speed dial until it shows 1/15. With the meter off, the needle should indicate at the orange f/2.8. If something different shows, you will need to back out the three grub screws which hold on the shutter speed knob a few turns each (do not fully remove them, they are easily lost), and lift off the knob, you will see the brass gears beneath, turn the gear until the needle indicates the orange f/2.8, then reinstall the knob.