10 things to test before buying a used DSLR

I was recently confronted to pick a used DSLR for a friend of mine so I was busy building a list of things I should be testing in each of these digital camera before I gave my final verdict.

1. Body inspection: Let’s take out the most obvious thing first, inspect throughly the body for any trace of damage or abuse.
Minor scratches are normal and should worry you a lot, more pronounced scratches aren’t harmful either but they are story telling about the history of the camera.

2. Auto Focus accuracy: Use a lens you already know to be focusing fine and test the auto focus accuracy of the digital camera by taking some “real life” pictures of well contrasted and well lit objects using the central focus point with the lens set to its widest aperture, download the pictures to your computer and check for front/back focus. Also make sure to check that all other focus points are working, no need to test them for accuracy.

3. Sensor inspection: Shoot a defocused white wall at f/22 download the picture to your computer and check it at 100% for sensor scratches.
N.B.: Some dust spots are normal, they are often even found on brand new cameras.

4. Shutter inspection: Ideally speaking check the number of shutter actuations and compare it with the shutter life cycle of the camera you are planning to buy. If it is impossible to know the actual number of shutter actuations, inspect the shutter curtain visually for wear and damage.

5. Colors inspection: I know that colors can easily be fixed and that they are factors of a lot of things, but I have seen some DSLR which colors are really really bad, just take a couple of shots in daylight with White Balance set to Auto White Balance and check the the colors looks “normal” with no real pronounced color cast.

6. Buttons inspection: Check that none of the buttons “stick” and all work as they should.

7. Flash inspection:Check the pop-up flash (if any) and flash hot-shoe.

8. Dead Pixel inspection: Take a picture with the lens cap on. Shutter speed: 1 sec, ISO 100. Then use any dead pixel analyzer to know the number of dead pixels. Even though dead pixels are quite normal, if you get a large numbermore than 15-20 for such an exposure of dead or hot pixels resulting from this test you might want to consider another DSLR.

9. Connection inspection: Make sure all the connection of the camera are working, you can connect it to a computer to download the pictures, that the TV out connector is working, and if you can also test the remote shutter release connection.

and last but not least
10. Serial Number inspection: If you have no idea about the seller you might want to check the serial number of the camera you are about to buy against any Stolen Photography Equipment Registry like the one on Photo.net.

I would like to thank my friend Petteri Sulonen for helping me out in building this list.