Buying a Used DSLR—How To Avoid Getting Burned
So you've decided to buy a used DSLR. Good decision! You will find a very wide selection from upgraders as well as unsettled people who constantly switch back and forth between Canikontax, in great condition, at bargain prices.
You're worried however. No warranty. No Guarantees. And most likely, no money back if there are problems. Worry not! This handy guide explains everything you need to know about how to avoid getting burned.
First thing you should know: A DSLR is a precision instrument which has many carefully aligned parts both moving and non-moving, so make sure you get to test it before you put down your money. Basically, don't have one shipped—only meet face-to-face.
I've put together a list of things I usually check for when I buy a used camera body (I've bought quite a few of the things lol).
Now in order to test and check a camera, you have to know what to look for as well as the ins and outs of the camera.
Before You Meet The Seller
Download a pdf of the camera manual, read it carefully. Print it out or put it on your phone/tablet/whatever and bring it with you when you go to meet the seller.
I can not stress how important this is!
Charger Check: Make sure that the charger works.
Initial Battery Check: Check to make sure that the battery is genuine, not an aftermarket Chinese one. Turn on the camera and note the battery reading.
Accessories Check: Make sure all the cables, focusing screens, straps etc. are there
Cosmetics: Give everything a once-over, look for any cosmetic damages that may indicate signs of abuse or internal damage
Mirror Box Check: Go ahead and remove the lens if there's one on it. Check the mirror box for any dust issues.
Terminals/Leads: Check the battery door and compartment for corrosion. Also check the memory card door and compartment for stuff like wear/tear and bent pins. Check the hotshoe for rust/corrosion
Tripod Mount: Check the tripod mount for corrosion. If you can, check to make sure that it mounts to whatever standard it is—typically 1/4-20 UNC.
Diopter Control: Check to see if the Diopter is working. Have a look through the lens. Play with the diopter until the GUI is sharp.
Viewfinder Dust: Look for any major dust issues in the viewfinder. Used bodies will usually have some, it's not a big deal. Just make sure it's not excessive.
AF Test: If you have a lens (and you really should have a lens), check to make sure that autofocus is working properly. Switch the camera to full auto or "P" mode and take a few shots. You've just adjusted the diopter for you eye, so whatever you focus on should also be sharp in your viewfinder. Look at the pictures you've just taken and make sure that whatever you focused on is sharp. If it isn't, there may be issues of lens/body misalignment or miscalibration.
Meter Check: Cycle through the various metering modes. Evaluative/Matrix, Avg, Spot, etc—you might have to switch out of Auto mode into one of the PASM/ PAvTvM modes to do this. Make sure it gives you expected readings. e.g. Using the spot meter and pointing right at a light source should give you a much faster shutter speed compared to Evaluative/Matrix metering.
Modes Check: Go through the rest of the mode dial. Make sure that all the modes do as intended. Take some shots and video if the camera has a video mode.
Rear LCD Check: Take the time to review the picture you just took. Look for things on the LCD like stuck pixels and discolouration. Discolouration may indicate water damage.
Top LCD Check: If the body has a top LCD, check and make sure that the display is healthy. Check the backlight illumination to make sure it works.
Aperture/Shutter/ISO Check: Switch the camera to "M". Make sure that adjusting aperture, shutter, and ISO produces expected results.
Burst Mode Check: Put the camera in burst mode. Fire off a continuous burst to make sure that the camera cycles normally. Hold the shutter button down until you fill up the buffer—the camera will cycle much slower once the buffer fills up. Wait for the buffer to flush to the memory card. Make sure it functions as it should.
Mirror Lockup, Live View, etc: Review any other (non major) features of the camera to make sure that it functions normally
Wasn't that fun? Now finish up.
Final Battery Check: You've just put the camera through some use. Check to make sure that the battery hasn't drained excessively—a sign of an old/dying battery.
Before You Give Your Money Away: During the course of your testing, you will probably have noticed any other issues. Things such as sticky dials, peeling grip, unresponsive buttons, etc. You're looking at a used item, so there's bound to be some wear and tear. Make sure you're comfortable with the camera and anything that may not be in like-new condition. Make sure that the camera justifies the asking price.
Good luck and happy shopping!