Specifications

OPEN-APERTURE AND STOP-DOWN METERING LENSES

Open-aperture SMC Pentax lenses have a diaphragm coupling

lever on the back of the lens which couples with the camera body

to permit open-aperture metering. The ultra telephotos do not have

a diaphragm coupler, so they must be used with the stop-down

metering system. Use of the Auto-Extension Tube Set K permits

open-aperture metering.

Use of other K Series accessories - standard Extension Tube Set K,

Helicoid Extension Tube K, Auto-Bellows K and Bellows Unit K -

requires stop-down metering. Whenever any one of these is used

between the camera body and an SMC Pentax lens, the stopdown

metering system must be used.

RESISTANCE TO TEMPERATURE EXTREMES AND CHANGES

The temperature range at which your camera will continue to function properly stretches from 50°C to -20°C.

However, resistance to cold could be hampered by oil which has become dirty. Therefore, if the camera is to operate

at full efficiency in very cold conditions, it must be overhauled and all oil must be replaced. Sudden changes in

temperature will often cause moisture to condense inside or outside your camera. This is a possible source of rust,

which may be extremely damaging to the mechanism. Furthermore, if the camera goes from a warm temperature to a

sub-freezing one, and if tiny drops of moisture freeze, further damage may be done by their expansion.

Thus, sudden temperature changes should be avoided as much as possible. As a guide, a temperature change of 10°C

should be allowed to take place gradually over a period of at least 30 minutes. If this is not possible, keeping the

camera in its case or bag will help somewhat in minimizing the effects of a rapid temperature change.

Extremely low temperature reduces the efficiency of the battery. Therefore, the camera should be protected against

low temperature. Put the batteries into the camera right before shooting. For extremely low temperature, use new

batteries.