Archived posting to the Leica Users Group, 2000/11/02

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Subject: [Leica] Whose confused??? Erwin didn't say that.... What did he say???
From: "Birkey, Duane" <dbirkey@hcjb.org.ec>
Date: Thu, 2 Nov 2000 09:12:06 -0500

In the one I originally snipped it and part of that is below.....it appeared
Erwin was saying it to be at least 1920 x 2880....  But is he then saying
that it is then needs to be multiplied by 4 or 7680x11520 to get the 40 lp
resolution he was talking about???

If Erwin is saying 1920 x 2800, that seems low being used to the resolution
from scans in photoshop.... but we are dealing with at least two seperate
animals.... one being original CMOS capture and the other scanning from
film.  The reason I say that is based on the comparisons of film and the D30
(which has 1440 x 2160 resolution).... although according to Reichmann....
to get a 10 x 13 print that equals film from the D30 on his inkjets, you
need to step up res with Genuine Fractals or something...

If it is 7680 x 11520 Erwin is refering to... well that is a monster 253.2
mb file.  12.8 inches by 19.2 at 600 dpi.  If that is not equivalant to
film...am I missing something???

On the other hand... If Jim Brick thinks Erwin's explanation is correct....
I would be hard pressed to believe that it is wrong.  It might take some
serious explaining for all of us to figure out what they are saying though
as I think we are making some wrong assumptions based on Erwin's frustration
in his response...   From experience I know a number of brilliant electrical
engineers who can't explain things in a coherant manner.... they can design,
build and fix anything electronic... but just don't ask them to explain
what, how and why to a non-engineer...  

Duane Birkey
HCJB World Radio
Quito Ecuador
Duane's Photographs of Ecuador
http://duane_birkey.tripod.com


I'll snip a bit more from my original snip of what Erwin wrote:

So on the
assumption of 40 lp/mm (80 lines) as an industry standard (BTWthis
resolution gives salon quality exhibition prints of size 40 x 50cm, a 35mm
negative capturing 24 x 80 x 36 x 80 lines has a number of pixels or image
points of 5.5 million. This figure is independent of whatever grain size.
Now a new CMOS chip with 16.8 million pixels needs 4 pixels to repesent one
image point. The 16.8 million divided by 4 gives more than 4 million true
image points.