From: Chris Malcolm on
In rec.photo.digital stephe_k(a)yahoo.com <stephe_k(a)yahoo.com> wrote:
> Chris Malcolm wrote:
>> In rec.photo.digital Paul Furman <paul-@-edgehill.net> wrote:
>>> stephe_k(a)yahoo.com wrote:
>>>> MikeWhy wrote:
>>>>> "Alfred Molon" <alfred_molon(a)yahoo.com> wrote in message
>>>>> news:MPG.2602e994c867cf0598c25c(a)news.supernews.com...
>>>>>> In article <hn93o5$v2c$2(a)news.albasani.net>, stephe_k(a)yahoo.com says...
>>>>>>> B: Is the MF glass resolving enough to do anything if it does
>>>>>>> resolve as
>>>>>>> highly. i.e. are you actually gaining anything.
>>>>>> You mean MF glass is unable to resolve 40MP?
>>>>> 6 micron pixel pitch is 167 lines/mm.
>>>> Which very few if any MF lenses can resolve.
>>
>>> If you want to get the most out of a lens' resolution, 3 pixels per
>>> detail is pretty good.
>>
>> Every lens I've got, including the 18-250 zoom, can do that in its
>> central area under optimum conditions of light, contrast, and
>> aperture. The difference is that the best can do it in a wider range
>> of conditions, apertures, and image area.

> So you are talking about MF lenses?

No, APS-C DSLR. But the point I was reaching for is that in recent
years lens design and manufacturing technology has improved a lot. If
it's necessary it shouldn't be a problem improving MF lenses.

--
Chris Malcolm
From: stephe_k on
David J. Littleboy wrote:
> <stephe_k(a)yahoo.com> wrote:
>> David J. Littleboy wrote:
>>> <stephe_k(a)yahoo.com> wrote:
>>>
>>>> So shooting a hand held quick test of the very center of the lens on a
>>>> different camera proves this Pentax can resolve enough for this pixel
>>>> density to be useful beyond marketing numbers? OK, I'm sure you believe
>>>> this :-)
>>> It clearly shows that there's no problem producing sharp images with MF
>>> lenses at that pixel density, and that your claims of unsurmountable
>>> problems are silly, unfounded BS.
>> My only claim was this MP density isn't needed at the resolution these
>> lenses have.
>
> That's a stupid claim, then. But it wasn't your claim: you were clearly
> claiming that the resolution of MF lenses wasn't adequate. And that's dead
> wrong.

I love it when it turns to personal insults, this should prove you are
right!

>
>> I'd be shocked if you could see any difference in say a 30MP version of
>> this same crop camera.
>
> That's bad logic. Think about it: your "you could[n't] see any difference"
> isn't transitive. Why bother with 30MP when you can't see the difference
> between 30MP and 24MP. Why bother with 24MP when you can't see the
> difference with 20MP. Do this a few more times, and 1 pixel will be all you
> need.
>

Actually it's pretty sound logic, if you can't see ANY difference
between 30MP and 40MP in the camera system with the same size sensor, it
IS purely marketing. If you can see a difference between 20MP and 40MP
but you can't between 30 and 40 then clearly 30MP is the "threashold"
for that system. What you just posted is an over simplified exaggeration.

If you actually reread what I wrote, I said MF lenses don't supply the
resolution -requiring- this high a pixel density.

Stephanie
From: stephe_k on
Chris Malcolm wrote:
> In rec.photo.digital stephe_k(a)yahoo.com <stephe_k(a)yahoo.com> wrote:
>> Chris Malcolm wrote:

>
>> So you are talking about MF lenses?
>
> No, APS-C DSLR. But the point I was reaching for is that in recent
> years lens design and manufacturing technology has improved a lot. If
> it's necessary it shouldn't be a problem improving MF lenses.
>

But if that is the case, then this camera body is vaporware until they
make better optics was my point. No doubt at some price they could make
better optics.

Stephanie
From: Bruce on
On Sat, 13 Mar 2010 22:46:36 -0500, "stephe_k(a)yahoo.com"
<stephe_k(a)yahoo.com> wrote:

>Chris Malcolm wrote:
>> In rec.photo.digital stephe_k(a)yahoo.com <stephe_k(a)yahoo.com> wrote:
>>> Chris Malcolm wrote:
>
>>
>>> So you are talking about MF lenses?
>>
>> No, APS-C DSLR. But the point I was reaching for is that in recent
>> years lens design and manufacturing technology has improved a lot. If
>> it's necessary it shouldn't be a problem improving MF lenses.
>>
>
>But if that is the case, then this camera body is vaporware until they
>make better optics was my point. No doubt at some price they could make
>better optics.


But they already have made a better lens - there is a new 55mm
standard lens for the 645D. It is advertised as "the first of a new
series":

http://www.pentax.jp/english/news/2010/201007.html





From: Bowser on
On Fri, 12 Mar 2010 18:16:30 -0500, "stephe_k(a)yahoo.com"
<stephe_k(a)yahoo.com> wrote:

>Bowser wrote:
>>
>>
>> <stephe_k(a)yahoo.com> wrote in message
>>> My point was that pixel pitch below a certain level with most MF glass
>>> is pointless other than for marketing reasons. And is likely to have a
>>> threshold different from what could be useful with 35mm based Dslrs.
>>> It's sorta like thinking how using techpan might be useful with 35mm
>>> film camera with really good glass, it's overkill for a 120 film
>>> camera and no way could you ever use the resolution the film is
>>> capable of with MF lenses.
>>
>> Here again, my experience with a special B&W file in the Hassy seems to
>> indicate otherwise.
>
>I'd agree most blad optics don't fit this statement. But this isn't a
>blad camera :-)
>
>Stephanie

No, but the Pentax optics I used, the manual focus 645 lenses were
excellent. Optically they were wonderful, and mechanically they were
very rugged. The two Pentax 645 zooms I had were dreadful, though.
Nice useful ranges, but the clarity just wasn't there, and using those
zooms on this new digital body might disappoint. Hell, they *will*
disappoint!

Anyway, I don't have it any more, and have no plans to purchase any
gear beyond the Canon 70-200 f4 L IS next week. For me, the 5D II is
all I need, and changing gear will not improve my photos, that's for
certain...