08.25.2009 08:10 AM
Do you know what to expect from the camera you'll be using tomorrow? Most videographers don't always use the same camera on every shoot. News shooters are often required to share cameras. Freelancers never know what they'll be handed. Even rental cameras, which have been thoroughly tested before being sent out, should be put through a brief getting-acquainted session. Will your images be properly exposed and in focus? Is the lens ready to fall off? Here's what to look for:
Check first for gross mechanical defects. Wiggle the viewfinder to be sure it's securely attached and that there is sufficient tension to prevent the eyepiece from flopping around. Press down on the lens-mount locking lever to ensure that the lens is on tight. Carefully inspect the shoulder strap for signs of wear, making sure it is completely threaded through all buckles and that the camera attachment points are not bent or broken.
Turn the camera on and check out the viewfinder. Adjust the diopter to provide the sharpest image and tweak the brightness, contrast and peaking to suit your needs. Switch off the tally lights unless you really want everyone to know when you're rolling tape.
Shoulder the camera and wiggle your wrist while your right hand is clamped around lens. Any movement, no matter how small, should be carefully investigated. The lens might not be seated securely in the mount or, as is sometimes the case, the internal screws that hold the lens together may have loosened. If you're lucky, a loose lens will only cause focus problems.
Less fortunate videographers who fail to notice a loose lens can be left holding the lens – and nothing else – when the camera breaks away and falls to the ground. Complete your external inspection of the lens by making sure the macro-focusing button and focal-length doubler lever at the rear of the lens are in their detent positions.
Once you've ascertained that the lens is nice and tight, find a fairly dark area where you can open the iris to its widest setting and do a quick back-focus check. Focus on a distant object while zoomed to full telephoto and then watch to see if the image stays sharp as you zoom out. Any problems that are apparent in the viewfinder mean you are REALLY in trouble. (As always, using an external monitor and a test chart is the only way to do a truly accurate back-focus check.)
Now zoom back out to maximum telephoto and take a moment to see if the lens actually achieves infinity focus when the focusing ring is rotated all the way to the internal stop. Lenses that have seen a lot of service sometimes overshoot infinity, making it necessary to carefully scrutinize the image in the viewfinder when focusing on distant objects instead of simply turning the focusing ring until it stops.
If you're shooting in the field without any access to a waveform monitor, it's important to confirm that the camera's automatic exposure settings conform with your expectations. Zebra-stripe viewfinder indicators, often set to somewhere between 100–110 IRE, are sometimes calibrated to flag a much lower value. Some cameras even have two different sets of stripes, one calibrated to indicate what is being clipped, the other set to show up over properly exposed Caucasian skin. If you aren't sure what a camera's zebras are set for, you could be in for a big surprise when your tapes are screened.