[MF3D.FORUM:876] Re: Thanks Paul

["don lopp" <dlopp@xxxxxxxxxxxxxxx>]

Looks like a fair assesment of  lens resolving powers but I dont see the
value considering the poor resolving power of all of the color films
curantly available , that I have tested
----- Original Message -----
From: "Bill Glickman" <bglick@xxxxxxxx>
To: "Medium Format 3D Photography" <MF3D.Forum@xxxxxxxxxxxxx>
Sent: Thursday, June 01, 2000 10:05 AM
Subject: [MF3D.FORUM:632] Re: Thanks Paul


> Brian
>
>       I was very familiar with the test results of C Perez.  C Perez
> purposely did not test the LF lenses at anything smaller than f11.  Most
> were tested at f16, f22, and f32.  The very best LF lenses of today can
> resolve about 70 lpmm, such as the super symar XL's.   However most still
> average in the 60's, while slightly older lenses perform in the 50's lpmm.
> New MF glass has resolved up to 130 lpmm while average MF modern glass
still
> averages about a 100 lpmm.  However, this is a mute point when it comes to
> MF stereo since we all agree the resolving powers of all these lenses are
> more than what is required in MF stereo.
>
>       My only point was, at wider apertures where it sometimes would be
> desirable to shoot MF stereo to prevent blur from wind or shooting moving
> subjects, etc.... With MF, you have that option.. while LF lenses are very
> very poor at the wider apt., say f5.6.   Even both my Super Symar XL's
> performed poorly when shot at 5.6 and 8.  It becomes noticeable through a
4x
> loupe.
>
>  I hope I did not offend any LF lovers out there, I own 10 new LF lenses,
so
> I am a big fan of LF.  But I sure have a lot of slightly blurred shots in
> 8x10.
>
>
> Regards
> Bill G
>
>
>
>  ----- Original Message -----
> From: "Brian Reynolds" <reynolds@xxxxxxxxx>
> To: "Medium Format 3D Photography" <MF3D.Forum@xxxxxxxxxxxxx>
> Sent: Thursday, June 01, 2000 4:33 AM
> Subject: [MF3D.FORUM:629] Re: Thanks Paul
>
>
> > Bill Glickman wrote:
> > > But what I was mainly referring to was a deciding on a versatile
> > > lens, one that can shoot at 5.6 if you are shooting waves crashing
> > > on rocks...(achieve stop motion) in which case many LF lenses would
> > > produce very poor results.... and this is due to their very poor MTF
> > > curves at these wide apt.  So bad it would be noticeable in the
> > > viewer when shot wide open..  MF glass, has excellent sharpness over
> > > almost the entire f stop range, usually tailing downwards at the
> > > smallest openings.  But in still situations, I totally agree, stop
> > > all the way down, you are not enlarging enough to allow diffraction
> > > to rear its ugly head!
> > >
> >
> > You shouldn't be so quick to judge LF lenses inferior.  A little while
> > ago Kerry Thalmann, Mike McDonald, and Chris Perez did a series of
> > lens tests on MF and LF lenses.  Their intent was to cherry pick the
> > best lenses available to them.  In the course of their testing some
> > people sent them additional lenses to test.  You can see the tests and
> > conclusions at <URL:http://www.hevanet.com/cperez/>.
> >
> > Basically modern LF lenses perform just as well as modern MF lenses,
> > and 50 year old LF lenses (Kodak Ektars) are just about as good as
> > modern ones.  They also showed that you do not have to stop all the
> > way down (even with 8x10).  Of course LF has swings and tilts to
> > maximize DOF.  They did find a correlation between price and
> > performance.
> >
> > --
> > Brian Reynolds                  | "Dee Dee!  Don't touch that button!"
> > reynolds@xxxxxxxxx              | "Oooh!"
> > http://www.panix.com/~reynolds  |    -- Dexter and Dee Dee
> > NAR# 54438                      |       "Dexter's Laboratory"
> >
>