Re: Is EBL a construct? Was: Re: [Leica] M6 TTL .58 accurate witha Noctilux?

[Dante A Stella <dante@umich.edu>]

I will rephrase these questions into a format that is more pointed.  And yes, I will see
if I can locate a copy of Osterloh's book, although I am not sure it will answer any of
these questions.  Mr. Small may be able to shed some light on this, especially the
development of the III vs the M3 and Zeiss's theories...

Question 1.  At more than 100% mag - is a III really as accurate as an M3 or M6 0.85
solely by virtue of the EBL?

Question 2.   At less than 100% mag - are the minimum EBLs needed, as computed today,
computed using (a) the limit of human resolving power or (b) the average human resolving
power?

This is relevant to me because we are often faced with two bodies presenting the same EBL
- - one long actual base (and low mag) and one moderate with higher magnification).  If the
determinant is the best human sight, it would seem more sensical to go for the lower
actual BL, higher mag, equal EBL model.

Cheers
Dante

Dennis Painter wrote:

> Go back and read your summary. That's not a question, you try to present
> a case that EBL has no meaning.
>
> Perhaps I misunderstood and you were just saying you don't know what EBL
> means, if so, fine, just say that and spare the conjecture.
>
> If you really want to do some research you could start with Osterloh's
> book.
>
> Dante Stella wrote:
> >
> > Why don't you read what the message said - that it was a question about
> > the analytical model being used, with a short statement of why I had that
> > particular question.  Need every sentence end with a question mark?  Is a
> > modal verb like "seem" too subtle?
> >
> > I have not yet seen a treatment that addresses how 150% magnification can
> > overcome a short base.  Maybe you could point one out.  When you see the
> > "can my 0.58 focus a Noctilux" thread, and the only references are to
> > Erwins materials, which neither address this point nor talk about the
> > assumptions underlying EBL, it becomes clear that these "extensive
> > studies" and "proper analytical techniques" are not accessible.
> >
> > If you look at the questions on LUG, 75% can be answered by common sense.
> > So why is a question which requires a touch more thought than the filter
> > size of a Summicron provoke an attack?
> >
> > ------------
> > Dante Stella
> >
> > On Tue, 3 Oct 2000, Dennis Painter wrote:
> >
> > > Dante A Stella wrote:
> > > >
> > > <snip>
> > > >
> > > > So in sum, it would look like EBL is a questionable concept for magnifications
> > > > over 100%, and that use of EBL for magnifications lower than 100% is really just
> > > > a shorthand for accuracy in the hands of an average user, accuracy which may or
> > > > may not be reflective of any particular individual.
> > >
> > > Good grief!
> > >
> > > Rangefinder accuracy has been studied a great deal with proper
> > > analytical techniques.
> > >
> > > How about you do some research on other's studies before presenting a
> > > summation. Maybe then it will be of more value to the LUG.
> > >
> > > Dennis
> > >