is my light metre broken?

[IvanMyring]

I bought a used canon ftb recently, and it didn't have batteries. So having bought batteries yesterday, I tried them out. The meter didn't work, so I tried to scratch off the corrosion on the surface with a screwdriver. I think I got most of it off as the surface is now shiny in the centre. The meter works on the test setting (it moves up slightly on ASA 100 and 1/1000 in check mode), but when I point it at anything other than a light source (ie a light or lamp) the needle stays right at the bottom. This is indoors, but in a fairly well lit room at night, at these settings:
ASA 200
Shutter 1/125
F1.8
The exposure needle only moves up when I change the ASA to 800-1600 or change the shutter to slower than 1/30. When pointed directly at a 60W bulb (at ASA 200 Shutter 1/125) it moves up about 4/5 of the way to the top. I haven't tried it outdoors as the weather has been awful.
The camera is supposed to take a 1.35v battery but I use a 1.4v battery, as they are easier to get.
Could anything mentioned above be the problem (battery, no cleaning the contact enough, light conditions etc), or is it just broken?

 

[compur]

The exposure needle only moves up when I change the ASA to 800-1600 or change the shutter to slower than 1/30. When pointed directly at a 60W bulb (at ASA 200 Shutter 1/125) it moves up about 4/5 of the way to the top. I haven't tried it outdoors as the weather has been awful.

Sounds like the meter is working. What are you expecting it to do that it isn't doing?

If the meter is off scale under a particular lighting condition then you change your aperture/shutter speed until the needle is where it's supposed to be. If you have to set a shutter speed below 1/30 then that is what the meter is telling you is required for proper exposure at the aperture you've selected. That's how meters work.

 

[fokker]

Seems about right to me. Try it outside during the day using the 'sunny 16' rule. That is, on a sunny day outdoors, a correct exposure at f/16 should be more or less 1/ISO. So at 200 ISO your shutter speed should be 1/200s.

 

[vintagesnaps]

Go outside on a sunny day and that needle ought to really move! It's telling you the lamp indoors isn't giving much light for a camera to use.

For corrosion DeoxIt is supposed to be good but I haven't tried it yet (have a couple of thrift store finds that I'm going to try it on).