Canon 450d - overexposing to hell

[Cactussed]

Guys

As above, the camera's light meter is over expsing to hell. Seems to be just with my sigma 18-125 lens however, as my prime lens seems to be working alright.

Is this common? Presume its simple somehting which needs to be cleaned / serviced on the camara or possibly the lens?

Would appreciate some advice.

Ta

[andy-xr]

OK, not knowing whether you've done the basics or not....whats happened?

Have you got ISO set to something silly, or a load of EV dialled in? Bit more detail on what you've done

[Scott330ci]

Mine overexposes quite a lot with anything other than a Canon lens.

[andy-xr]

Sorry, didnt read the bit about the prime being good

[Cactussed]

That's no prob.
On all modes, including manual its doing it, irrespective of ISO.

Light meter says perfect exposure but you can look at the settings and know with a sense check they are wrong and sure enough, the photo is blown out so as to be almost unusable.

[MartinP]

Maybe the aperture is stuck wide open on the Sigma lens. Try putting the camera in manual, set the shutter speed to a few seconds and the aperture to f/22. If you then fire a shot you should be able to see the aperture close right down for the shot if its working correctly.

[Cactussed]

Its not that. It's definitely the light meter signal.
I can set the sigman lens manually to get decent exposure (by adjusting either shutter or aperture) however the light meter says its all massivly underexposed.

Very odd, as I've never encountered anything like this before.

[GetCarter]

I've got a Nikon lens that always over exposes. Gave up trying to fix it and now just stop down the body when it's on, and it's fine. Not the perfect scenario, but pragmatic.

[tangerine_sedge]

Cactussed said:

Its not that. It's definitely the light meter signal.
I can set the sigman lens manually to get decent exposure (by adjusting either shutter or aperture) however the light meter says its all massivly underexposed.

Very odd, as I've never encountered anything like this before.

Have you tried cleaning the contacts on the lens? It's possible that the camera/lens can't communicate and the camera is going to some default setting?

Note the question marks - I don't really know

[Cabinet Enforcer]

The lens tells the camera what settings it can do, and can't let through 'too much' light, so the body must think the lens is at f1.0 or something like that and basing the metering off that.

Try popping it in manual and adjusting the aperture to a figure the lens should not be able to do (like f1.0) if you can do this then it is most likely a communication problem between lens and body.

[Seight_Returns]

Has the camera ever metered properly with this lens or is this something that's just happened ?

My 400d meters fine with my 4 Canon lenses but I've never been happy with the metering (often, but not always, underexposes badly ) with my Sigma 17-70 to the point that I'm about to give up on it.]

Edited by Seight_Returns on Thursday 23 September 21:43