Pentax 645N Autofocusing Comes To Medium Format SLR
Evolution is inevitable in
all camera formats. The past two or three decades have witnessed a vast
degree in sophistication, automation, and electronicization of all types
of photo equipment. The Pentax 645N was the first medium format SLR
to incorporate autofocusing. There are others now, but this was the
original and Pentax got there first just as they did decades earlier
with practical Through The Lens (TTL) metering in the pioneering Asahi
Pentax Spot-matic introduced in 1964. Who knows what's next? Perhaps
sometime early in the soon to arrive next millennium an autofocusing
large format camera will come into being. Only time will tell. |
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If you are not particularly
familiar with medium format cameras, don't be lulled into the belief
that these are particularly easy loading and operating cameras. They do
require a fair amount of user know-how and dexterity when compared to
their nearly totally automated 35mm or APS format cousins. Just loading
the light-tight black paper backed 120 film into the film holder is slightly
tedious. First the empty metal spool has to be placed into the take-up
slot and the new roll leader has to be threaded into a slot in the empty
spool. Then the film is wound slightly until an arrow (on the backing
paper) shows opposite a mark inside the camera. This is done before you
even place the holder into the camera. Extra film holders are available
that can be pre-loaded for faster film changing when working on fast paced
events or subjects. Then you must be sure to check, and if necessary,
reset the ISO setting since roll film does not have DX coding marks to
automatically set the ISO film speed. However, once the film is loaded
and the proper ISO film speed is set, operating this new 120 AF SLR is
quite similar to a conventional autofocusing 35mm SLR such as most of
us are familiar with. It even is held similar to a 35mm SLR since it includes
a built-in grip on the right side that often is an add-on extra on other
makes of medium format SLRs. |
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Any of three metering modes
are easily selected by simply moving a lever located below the shutter
speed dial. The choices are multi-segment, center-weighted, and spot metering.
The multi-segment metering is classified as "Dual Six Segment,"
read by two sensors located on both sides of the viewfinder measuring
the lighting condition in two different areas. A wide sensor covers the
entire field while a narrow sensor monitors just the central area. When
dictated by varying subjects you can choose pinpoint spot metering or
conventional center-weighted metering modes. Exposure compensation of
1/3 steps in a range of ± 3EV is possible. When you want to meter
a particular exposure, retain it and then recompose the image; simply
push in a small ML (Memory Lock) button conveniently positioned below
the LCD panel to hold that setting. |
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Logically clustered around
two primary control large dials on either side of the prism eyepiece are
most of the optional controls. The shutter speed dial to the right of
the viewfinder securely locks into the green "A" Automatic
or orange "X" flash synch setting. To make any change from
either of these two primary settings a button in the center of the dial
must first be pressed in before a change can be made. Thus you cannot
accidentally change the shutter speed easily. When set for any of the
remaining speeds of 4 sec to 1/1000 sec or Bulb there is just a positive
detent to hold the actual shutter speed selected. Just below this dial
is the switch for selecting any of the three metering methods with the
primary multi-segment metering marked in green for easier locating. |
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Technical Specifications Type: 6x4.5
format autofocus SLR camera with multimode TTL autoexposure control |
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