Archived posting to the Leica Users Group, 2001/11/05

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: Re: [Leica]: Vs: digital
From: George Day <george@rdcinteractive.com>
Date: Mon, 05 Nov 2001 12:57:05 -0800

Colin,

If you think that's impressive, you need to check out the EOS-1D.  It's
damned expensive (although no bad, considering a lesser camera cost over
$10k not long ago), but the results and performance are amazing.

Different applications, different tools.

on 11/5/01 10:45 AM, Colin at CJV@home.com wrote:

> I was at the Photo Expo in New York on Friday.  Canon had an interesting
> digital photography exhibition.  They stuck a model in a small studio
> setup, gave a photographer a D30 (Canon's "consumer" digital SLR, of
> modest specs), and started taking pictures.  The D30 does not use
> special lenses; it uses EOS lenses.  The photographer was using the
> 28-135mm zoom.  Moments after the picture was taken, it was transmitted
> to large video screens for the audience to see.  The photos were then
> printed out on one of Canon's high-end wide-paper printers.  They came
> out poster-sized, perhaps two feet by three feet - larger than anything
> I'd try with a 35mm camera.  They  passed the prints around; the prints
> were beautiful - lovely color, lovely contrast, nice sharpness, even
> from very close up.  The photographer explained that he was using only
> jpeg's, and not RAW or whatever images.  The guy printing the stuff out
> said all he did was about 30 seconds worth of Photoshop work - a little
> resize, a little crop, a little sharpening.
> 
> I'd like to be able to do this with my M camera, or something similar.
> 
> But you're right, in the end the pictures had all these false pixels and
> stuff.  It was awful.  I can't believe they went in public and
> humiliated themselves with that technology.  Really appalling.
> 
> C. 
> http://www.availabledark.com
> 
> 
> -----Original Message-----
> From: owner-leica-users@mejac.palo-alto.ca.us
> [mailto:owner-leica-users@mejac.palo-alto.ca.us] On Behalf Of Jim Brick
> Sent: Monday, November 05, 2001 12:40 PM
> To: leica-users@mejac.palo-alto.ca.us; leica-users@mejac.palo-alto.ca.us
> Subject: [Leica] Re: Re: Vs: digital
> 
> 
> At 06:56 AM 11/5/2001 +0000, George Day wrote:
> 
>> "not compatible"?  Whatever. Seems to work just fine for the well over
>> 90% of photojournalists shooting Nikon and Canon digital.  I'm sure it
>> would be quite adequate.  These are lenses, not spiritual beings.
> 
> 
> Unfortunately, George, you are not aware of the technology involved in
> digital sensors and lens resolution/MTF frequencies. Instead of me
> attempting to explain all of this to you, go to:
> 
> http://www.schneideroptics.com/white/kina.htm
> 
> and see why Schneider (and Rodenstock, and others) make lenses DESIGNED
> FOR 
> digital sensors.
> 
> Then go read about the Nyquist limitation at:
> 
> http://www.opus1.com/~violist/help/nyquist.html
> 
> Nyquist's theorem: A theorem, developed by H. Nyquist, which states that
> an 
> analog signal waveform may be uniquely reconstructed, without error,
> from 
> samples taken at equal time intervals. The sampling rate must be equal
> to, 
> or greater than, "twice" the highest frequency component in the analog
> signal.
> 
> In terms of lens resolution on digital sensors, it means that there must
> be 
> at least twice as many pixels per mm as the maximum resolution (lp/mm)
> of 
> the lens. If this is not true, the information gathered will be either
> partially or completely in error, and always aliased. See figure 4 in
> the 
> Schneider white paper. Modern Leica lenses have more resolution than can
> be 
> handled by digital sensors. They cannot make pixels small enough to be
> at a 
> frequency twice that of the resolution of Leica lenses. Five square
> microns 
> is about the limit of a pixel that can record enough light to produce a
> quality dot. And don't forget that it takes four pixels to record a
> single 
> COLOR dot (pixel).
> 
> The problem is that folks who do not understand the limits of digital
> electronics vs analog signals are moaning and groaning as to why Leica
> doesn't get with it and produce a digital M mount camera. They could
> certainly OEM a high level digital camera and put an M mount on it. But
> why? They would also have to but a resolution reducing filter behind the
> 
> lens in order to produce good digital photographs. So why bother? The
> Panasonic Leica digital camera soon to be on the shelves has a Leica
> lens 
> which is specifically designed to match the resolution capabilities of
> the 
> digital sensor.
> 
> There is no full size digital sensor made with a pixel size small enough
> to 
> take advantage of Leica lenses. Actually the reverse is true. Leica
> lenses 
> will cause the recording of false information via these sensors.
> 
> There is certainly more to it that simply bolting an M lens on to a
> camera 
> containing a digital sensor.
> 
> Over and out!
> 
> Jim
> 
> 
> --
> To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html

- --
To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html