Pentax's Tatamiya Interview Part II, #3

K.Takeshita marinerone at
Wed Nov 1 19:25:59 EST 2006

This 3 step DR system is one of many features we like to appeal to the
customers.  However, we cannot claim that all sorts of dust could be removed
100%.  The same applies to competitions as well.  Particularly in Japan
where the humidity is higher, dust hold moisture and sometimes it might be
difficult to remove those.  These cases have to be also taken care of.

When dust removal system is activated, the vibration due to the sensor
movement is conveyed to the body, causing some to feel somewhat odd.  For
this reason, DR system is turned off as default, but we recommend that it be
set for the activation at startup.

Q: Possible effect of DR on the battery life or the durability of it?
A: Battery power is applied to the DR system but it is only for 200ms
duration and would not possibly affect adversely on the battery life.  With
regard to the durability, the movements are caused by battery power and
magnetism, and there virtually is no mechanical or friction surface to wear
down. With regard to the impact force on CCD, we have discussed and
determine the shock durability with the CCD maker, then added Pentax¹s
guarantee margin and determined the allowable inertia setting.  In daily use
by customers, there is nothing to worry about the durability or the
deteriorating performance etc.

Q: What happens on dust gathered on adhesive sheet?
A: There is no possibility that 10,000 dust specks gather in one month.  In
normal use, any dust/speck would be very small compared with the area of
sticky tape.  We were rather concerned about the possible time deterioration
of the adherence ability of the tape.  Regarding this matter, we have
collaborated with a material maker to obtain much stickier sheet compared
with household double-sided tape. Accordingly, it is maintenance free for
the life of the camera.  If anybody had any special concern about this, we
are currently evaluating possible replacement of sticky sheet at service

Re New digital exposure modes

Q: Sensitivity priority mode and shutter speed/aperture priority mode are
unique.  What¹s the design intention for these modes?
A: Exposure is determined by 3 elements, namely, aperture opening, shutter
speed and sensitivity, however, in the case of film, the sensitivity is
fixed by the film and users cannot freely choose it during shooting.

Even after shifting to digital age, the basic idea of exposure has not
really changed since film era.  Idea always was how to set the programme
line by changing aperture and shutter speed, under a fixed sensitivity.
There is a function that will automatically increase the sensitivity when
the exposure approaches the shake limit, depending on the lens used. But
this is still at the level of ³supplement².

In other words, for the past DSLRs, there was no concept of freely
manipulate the sensitivity. We re-evaluated this fixed concept of ³first,
there is sensitivity² which has been dragged from the film era, and
installed a mode to adjust the sensitivity, just like setting aperture and
shutter speed. This was the origin of the concept for sensitivity priority
mode and shutter speed/aperture priority mode.

Specifically, in sensitivity priority mode, the sensitivity can be set at
either 1/3 step or 1/2 step by a wheel on the grip, and aperture and shutter
speed change accordingly.  In shutter speed & aperture priority mode, when
shutter speed and aperture are set by dials, the optimum sensitivity would
be set automatically.

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