New Canon F1 Perpetual Overexposure

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I have a Canon F1n #127294. Over the past several years (I never learn the lesson), it has consistently overexposed all shots. New batteries do not seem to address the issue, film does not matter, exposure mode does not matter, although in AE mode the problem is the worst. The only way I can calibrate and get a shot is to use an AE-1 and calibrate manually using the other camera's meter as a guide.

Some time ago I was brousing through a forum, which I cannot find anymore, wherein some respondents suggested that the battery type used and an issue with magnets controlling the shutter speed could be sources of problems.

When this first became an issue, it seemed to come on suddenly and remain a problem. My first response was to have it sent into a Canon repair center (Chicago I think) via my local photo shop in Ames, Iowa. I ended up writing a check for $260 which supposedly was for bringing the unit "up to spec" . I presupposed that meant it would work properly, (didn't). I supsect the camera sat on a shelf for two weeks and I got it back uninspected.

Anyway, this must be a common problem. The unit is in pristine condition otherwise. I need some direction. Thanks

-- Thomas D. Kolbo (tdk@midiowa.net), May 15, 2002

Answers

Thomas,

I personally would compare the suggested exposures of both cameras, the F1N and the AE-1, in a variety of lighting conditions, making sure to meter the same area, in the different modes, and record the findings in a notebook. Look for a pattern of discrepancy without burning any more film. With this knowledge in hand, find a repair person who will treat you and your camera personally. I know of a good technician for mechanical cameras, but for electronic models I would start investigating CRIS camera.

On another thought, what model focus screen is in the F1N? If it is perhaps a spot reading model, that could be throwing off the readings. Here is a link to the F1N manual, in case you don't have one. The focus screens are identified starting on page 51.

Good luck getting your camera to work properly.

-- John McDonald (jmcd@napanet.net), May 15, 2002.


One question first: does the meter in the F-1N give values that agree with the AE-1?

Two quick things come to mind:

Is the screen in the right way? If it is backwards it still fits but the photocell is covered and the exposure is way too much.

The curtain release electromagnet in the base of the body can be sticky and slow to release. Do any of the exposures seem much longer than what is dialed in? Mine used to stretch out a 1/2 second exposure to about 2 seconds until I cleaned the electromagnet armature.

Let us or me directly how it goes,

Cheers,

Duane

-- Duane K (dkucheran@creo.com), May 15, 2002.


I have an F-1N and don't have any exposure problems.

The above recommendations are good. If you want to use auto exposure, be sure you have a center-weighted metering screen in for best results. I use a spot metering screen and always use manual mode. Unless you only take photographs with neutral grey objects in the center of the frame, don't use auto exposure with a spot or partial metering screen.

It is also possible that your meter needs to be calibrated. If the meter readings from the AE-1 are applicable to your F-1N, then I would assume it is a meter problem and not a shutter problem. So if it is a calibration problem and your AE-1 meters properly, aim both cameras at a uniformly lit surface, see what the AE-1 reads, and then set the ASA dial on the F-1N so that it gives you the same reading. Try it under a variety of lighting conditions to be sure it is behaving in a linear way. If they reliably give you the same readings, just figure in that correction factor when you set the film speed on the F-1N.

-- David Goldfarb (dgoldfarb@barnard.edu), May 16, 2002.


All the axover answers are good. I would only add the following:

--To check expesures, use only slide film. That way, you can see directly the problems.

--Check the exposure compensation dial. It's the outside ring where the ISO (ASA) is set. It should read "1". If it does not, set it to "1" and see if that helps (it should).

--If you don't want to take the camera to a shop, and you do find a problem, you may be able to use the exposure compensation feature to compensate for the problem.

Good luck.

John

-- John C. Ratliff (cratliff@easystreet.ocm), May 19, 2002.


I own a pristine "new F1" and also a number of A1's and AE1's. My meter on the new f1 shows about 3 full stops of overexposure compared to the other cameras with same lens and lighting. All of my cameras have been checked out by technician. The shutter speeds on the new f1 are dead on, battery swaps don't seem to matter. I have been told that the meter unit is a sealed unit only servicable at the factory, leading me to believe it cannot be re-calibrated as easily as the a- body cameras. I would suggest using the exposure compensation dial and or changing the asa setting. Good luck!

-- Dan Sharp (Chronman@cox.net), July 19, 2002.


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