What am i supposed to check on a used Canon DSLR?

syphlix · Oct 12, 2009

Hi there,

I am considering getting a used 5d2 on craigslist, and aren't really sure what i'm supposed to check.

sensor, what else?

and how do i even see the sensor? on my XSi i did the mirror lockup thing, but when i look back there all i see is this gray matte plastic thing that doesn't look like the pictures of sensors that i've seen before... is the sensor directly there when i look in the hole in front of the body?

thanks in advance!

UUilliam · Oct 13, 2009

A sensor in the camera body is pretty much un-touchable, it has a few filters infront of it, Infrared filter, Anti-alias filter (thats why your edges are a little blurry)
and a few more so no, you wont see the sensor, basically take a picture with it, see if its okay, if its not then meh

Shutter auctions (number of times pressed) canon rate them at 100'000 i think.. before the button should be replaced

tirediron · Oct 13, 2009

Check to make sure the camera works. Download a copy of the manual (should be available from Canon's website) and have a basic understanding of the main functions before you go to look at it.

When you pick up the camera for the first time, look at the exerior carefully, especially the "corners" of the body and the bottom. Look for unusal scuffs or scrapes which may indicate that it's been banged or dropped. If you don't see any of that (and hopefully you won't), then push every button, turn every switch, etc. You're checking to make sure each control moves smoothly, doesn't hang up, switches/buttons don't have a 'gritty' feel etc.

Is the camera reasonably clean and dust-free? Remove the lens/body cap, have a look at the mirror box and surface of the mirror. Use the mirror lock-up to look at the sensor area (nb: You're actually looking at the mineral glass high-pass filter in front of the sensor. Is this clean and free of finger-prints, dirt, grim, etc. Look through the view-finder, is it reasonably clean? If not, I would be leery. Serious photographers tend to be careful with their gear and keep it clean.

Assuming all that goes well (and ask in advance if there will be a lens on the body; if not, bring one of your own) then turn the camera on and check the meter using the 'sunny 16' rule (Set the exposure mode to manual, and set an appropriate aperture, shutter-speed and ISO for the conditions WITHOUT looking at the camera's meter). Have a look at the resulting image on the camera's LCD and check the histogram. It should be reasonably well exposed. If it's severly under/over you may have a problem.

Take a number of shots in all modes and at varying settings to ensure that they all function correctly. If you have things like an external flash, bring it to check the hot-shoe and sync port. If not, ask the seller for confrimation (in writing preferably) that they work and that it can be returned if not. This likely won't help you too much if there is a problem, but it might.

Really, it's like buying a used car. Kick the tires, look under the hood, take it for a test-drive. If you see anything that makes you wonder, walk away.

~John