On Jul 8, 2005, at 8:00 AM, Joaquim Carvalho wrote:
Thanks for the reply but I meant William Maxwell from Precision Optics
How is Bill? He made me custom focusing screens for three
Rolleiflexes and a Hasselblad in years gone by. A good guy, if
sometimes a bit slow on delivery.
..I was able to aquire a few screens for the istD through Pentax
Canada, though the wait times were rather long.
The Ds screen is user replacable, and should be available through
your local Pentax dealer.
But there are no split-image screens for the digital *ists
available from Pentax, are there?
The D and DS models both have user interchangeable focusing screens.
Pentax does not offer a screen with a split image focusing aid ...
there are reasons for this. A German company, http://www.tekade.de,
offered such a screen (custom made by taking a screen from another
Pentax model and cutting it down to suit the D/DS body). It is known
to have some problems with metering functions, dependent upon lens
and meter pattern selected (Spot mode is what gives the greatest
problems).
Remember that a split image focusing aid isn't generally accurate
enough for critical focusing, they are an aid to getting the focus
into the ballpark quickly. You should always do critical focusing on
the matte-ground portion of the screen. Given the fact that AF
systems today can do a BETTER job of getting the focus "almost right"
than any split image focusing aid can, they are something of an
anachronism.
Godfrey
