Re: Introducing the remarkable new Pentax *Ist D

[graywolf]

Since the other systems are doing the same thing, what is the advantage 
in changing? Let's every A, F, FA, FAJ series lenses maintain full 
compatibity. M42, K, and M will work with limitations. Try using a FD 
lens on a Canon 1D. Try using a AIS or earlier lens on a D100. Hum..? 
Most Pentax lens made in the last 20 years work fine. If you were 
talking about a car, or a computer you wouldn't expect 20 year old stuff 
to work on a new one. Most folks consider anything 20 or more years old 
an antique. We sure are spoiled.



Peter Jordan wrote:

This is exactly what I mean by backwards capability.

For a long time I could use any k mount lens on any k mount body. The
introduction of teh crippled k mount stoped me using older lenses on new
bodies without significant compromises in metering capability.
Now the introduction of these new lenses tailored for the smaller ccd sensor
means that if I buy the new Pentax DA 80 -200 f/2.8 or whatever killer lens
gets launched, then I can only use it on digital Pentax bodies and can't put
it on my LX or MZ-S and get acceptable results.
This gives me 3 choices:-

Stick with my existing film based system and forget about digital because
most of my current lenses won't work on a digital body and any new DA lenses
won't work on my film based cameras.
Buy a second digital Pentax system to go along with my currrent stuff and
accept the compatability issues, so I can only use some lenses with some
bodies.
Sell all the Pentax stuff and start again.

I'm not particularly happy with any of the choices.

Peter

----- Original Message -----
From: "William Robb" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Sunday, September 28, 2003 4:52 PM
Subject: Re: Introducing the remarkable new Pentax *Ist D


----- Original Message -----
From: "Peter Jordan"
Subject: Re: Introducing the remarkable new Pentax *Ist D


It says in the press release, "The image circle in the DA-series lenses
is

designed to perfectly match the size of the CCD (23.5mm x 15.7mm)
incorporated in PENTAX's digital SLRs, optimizing the performance of
these

cameras."

My reading of that means that the image circle will be smaler than the
dimensions  of  35mm film, meaning that they can't be used on film
bodies.

Am I missing something here or is this the end of backwards
compatibility?

It means that the DA lenses won't be usable on film cameras, unless you
don't mind some vignetting.
In some respects, it makes sense to have lenses specifically for the
digital

format, in others it doesn't. From a design POV, they can make quality
lenses cheaper for the smaller image circle, since it is easier to make a
good lens with a smaller circle.
Thats why lenses like the FA77mm only cost a thousand dollars, while a
Rodenstock 210mm of similar quality for 4x5 costs a few grand.
I can't see the lenses being any smaller, since they are still K mount
lenses, and there are size restrictions based on that.
William Robb