Well, it boils down to the fact that the size of the lens has to do with
the size of the image it has to make. When the image size has to get
bigger, the lenses get larger, they become harder to make without defects,
and more expensive. That's also why TV cameras and some digitals can have
these ridiculously fast zoom lenses with huge ranges - because the sensor
is so tiny compared to a 35mm frame. Sure you could build a lens like that
to cover a 35mm frame, but it would be the size of a 55 gallon drum and
cost a million bucks.
Todd
At 07:15 PM 6/9/01 +0200, you wrote:
>William wrote:
>
>> This is just plain wrong. Your reasoning is logical, but is
>> drawn from an incorrect assumption.
>
>Exactly what assumption is incorrect?
>Anyway, the fact remains that most MF and LF lenses are significantly
worse than comparable 35mm system lenses for whatever reason. The Pentax
FA645 75/2.8, which is tested as equal or better than the 80mm Carl Zeiss
for the Hasseblad - hardly a piece of crap by MF standards, is performing
in a way that can only be compared to the cheapest consumer zoom for the
35mm system. Jostein �ksnes example with the A645 120/4 Macro, a lens that
tests better than Carl Zeiss 120 Macro for the Hasselblad, turned out as
significantly worse than the Pentax-K 135/2.5. The differences were so big
that they were clearly visible on a scanned image on a web page.
>Pentax doesn't make many MF lenses that compare well to their K-mount
lenses and apparently neither does Carl Zeiss.
>Some of us have learnt the hard way that MF lenses on 35mm camera is only
a last resort. I intended to base my system on using my MF lenses on my
K-mount body but have dropped that idea. Jostein (he can probably correct
me if my memory is off base) was of the same opinion but I convinced him
that the A645 120/4 Macro might be good enough to give it a try. He
borrowed(?) from the distributor the said lens (heralded as one of the best
MF lenses ever BTW) and tried it on a K-mount body and found that the
results was below par and presumably returned the lens.
>Its widely believed out there that larger format lenses are generally
worse (all thing equal) than comparable lenses for smaller formats. It is
said that lenses for the smallest format have the highest resolution (like
the lens for the Minox). I'm not saying this belief is true but it would
have been nice with some data that can explain the visible inferiority of
MF lenses on 35mm bodies that some of us clearly and undisputably observe.
>
>P�l
>
>
>
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