Filming at a slow speed will speed up the action on the screen and allow exposure in poor light. We have used cameras with automatic metering and manual override and found that in general the metering system does better than we do at getting the correct exposure. A CdS meter requires batteries, and in older cameras mercury batteries were specified. These batteries are officially no longer available in many countries, but a suitable alternative can usually be found. Check that a suitable battery is still available.
Some cameras have one set of batteries to power both the meter and the drive.
Sometimes the release has to be partially depressed to switch on the meter, which can be tricky. Some cameras, especially the compact cameras like the Canon 310XL, have reflex viewing using an aerial image which is good for framing the shot but which does not indicate whether or not the picture is in focus. Similarly, not all cameras have a rangefinder. A split-image rangefinder is the most common focusing aid but it is not the only solution. Other features The Super-8 cartridge design prevents backwind but camera designers have found ways to overcome this problem, not always reliably.