We now have one Norris LPC 90 in our rental inventory. This is a system that will automatically compensate exposure for changing light levels on the set when using the Norris single frame motors. Additionally, the light meter from the LPC 90 can be used with the Arri 435 single frame system in order to compensate exposure for changing light levels. The 435 single frame controller is designed to accept a special cable that plugs into the 4-pin Lemo connector that has been installed on the light meter by Norris. Clairmont is making this interconnect cable.

The LPC 90 system includes the LPC 90 controller, a modified Pentax 5 spot meter, 4-pin Lemo to 4-pin Lemo cable to connect the spot meter to the controller and 2-pin Lemo to 4-pin Canon power cable. Spare cables and instructions are included. The LPC 90 works with all Norris motors that are in Clairmont's inventory regardless of camera type. Complete set-up and operation details are in the instruction sheets that are included in the LPC 90 package. A brief description of the set-up and operation is as follows:

The Norris motor and capping shutter are installed on the camera as normal except the LPC 90 controller is used in place of the normal Norris controller.

The LPC 90 controller requires a 12 to 24 volt DC power source.

The light meter (spot meter) is plugged in and pointed toward the subject and the exposure is set on the LPC 90 controller. The spot meter can be mounted on the camera or a still type tripod. Exposure time, burst frames and interval are set on the LPC 90 controller. Once filming has started, the LPC 90 will increase or decrease the exposure time of the motor in order to compensate for the light level changes as sensed by the spot meter. This system does NOT control the iris of the lens, only the speed of the motor driving the camera shutter.

The resulting footage will have a consistent exposure from start to finish even as clouds pass over or as lighting conditions change such as sunset or sunrise shots. Obviously, practical exposure limits must be considered. The system may not compensate properly for very rapid or extreme changes in lighting such as a fast strobe in a dark room. The longer the exposure time, the more blurred a moving subject will be and the shorter the exposure time, the sharper the moving subject will be. When using the spot meter from the LPC 90 system with the 435 single frame system, the theory of operation is the same however the hardware is different. The spot meter is connected directly to the Arri control module and the LPC 90 controller is not used.