RE: [Leica] here's a concept, Summilux vs. Noctilux

[Richard Edwards <REdwards@Vetronix.com>]

I'm moved toward the same conclusion, that the 35 Summilux has
a DOF advantage over the Noctilux. But in the Noctilux's favor, it
gives half the exposure time at less than twice the magnification,
so that the 35 Summilux wide open would require twice the exposure
time at more than half the magnification (2x35 > 50), giving the
handholding
edge to the Noctilux.

But are we all so skilled that we can pull a f/1 lens into dead-on
focus in dark conditions?

Unhappily, I don't own either lens.

A lens that comes to mind here is Canon's 24mm f/1.4L, which
has both a DOF and handholding edge over a 50 f/1.0 lens. It's
fun to drive because the lack of visible shake through the viewfinder
convinces you that you can shoot under a pile of coal in a dark cellar.

- -Al

The Dvorak Keyboard:
   pyfgcrl
aoeuidhtns
qjkxbmwvz


> -----Original Message-----
> From:	Alan Ball [SMTP:AlanBall@csi.com]
> Sent:	Friday, February 12, 1999 10:11 AM
> To:	leica-users@mejac.palo-alto.ca.us
> Subject:	Re: [Leica] here's a concept, Summilux vs. Noctilux
> 
> Ted
> 
> The idea is that the depth of field is quite a bit wider at same
> distance for a 35mm at f1.4 than for the 50mm at f1, thus leaving more
> room for 'acceptable error'. At same magnification whatever the focal
> length, f1.4 is more forgiving than f1 (and less than f2). Seems
> obvious
> to me.
> 
> I have no figures right here, but they were published on this list,
> arguing on the precision of the M6 rangefinder and the acceptable
> tolerance between the exact point of focus and the point of focus
> indicated by the RF. Just as a 50mm at f1.4 is easier -or safer- to
> focus (precisely) than a 75mm at f1.4.
> 
> So my idea, which is also supported in the LHSA article pointed to me
> by
> J. Beal ( http://wanda.pond.com/~lhsa/articles/summilux.html ), is
> that
> the most efficient 'master of darkness' in the M range might well be
> the
> 35mm f1.4-Summilux (asph) rather than the Noctilux, the 1 stop
> advantage
> of the Nocti being compensated by the probable better tolerance to
> slower shutter speed (1 stop ?) of a wider angle and by the security
> brought in by wider DoF....
> 
> Or am i missing something here ?
> 
> Alan
> 
> Ted Grant wrote:
> > 
> > Alan Ball wrote:
> > 
> > >And another question: isn't focusing MUCH more reliable for the
> 35mm at
> > >f1.4 than for the 50mm at f1 ?>>>>>
> > 
> > Hi Alan,
> > 
> > I really don't see why if the rangefinder is accurate, it's going to
> be
> > accurate for any attached lens, f 1.0 or 1.4.
> > 
> > As long as those two little images come together correctly that's
> what
> > controlas the in focus and not the aperture.  I think.
> > ted
> > 
> > Ted Grant
> > This is Our Work. The Legacy of Sir William Osler.
> > http://www.islandnet.com/~tedgrant
>