24-hour surveillance gets a boost from Pentax

The new Pentax 8~144mm day/night zoom lens can successfully deal with all wavelengths of light – from daylight into IR (up to 900nm) - and remain focused throughout this range.

In the past, one could set up monofocal lenses under IR and night-time conditions by fully opening the iris and setting the focus.  Then with the automatic closing of the iris in daylight, one would hope that the resulting increase in the depth of field might compensate for the shift in the focal point and keep the image sharp.

The much wider range of focal lengths involved in the use of zoom lenses, however, makes this method undependable.

Under normal atmospheric conditions, various wavelengths of light from sources as diverse as halogen, sodium or natural moonlight would be present and can throw images out of focus.  The new Pentax lens is designed not to be ‘led astray’ in these conditions.