[Leica] Re: The M7d

[Jim Brick <jim@brick.org>]

At 10:12 AM 2/20/2002 -0500, Magnessbill@aol.com wrote:

>And that is the reason for the shutter , to protect the CCD when a lens is 
>removed. IMHO, the reason for non-interchangable lenses, they don't put a 
>shutter in at all- saves money.
>Bill


Correct. And the reason all digital cameras, except those built on a big 
SLR chassis, use zoom lenses is because these zooms are designed for 
digital and have the lower resolution/MTF designed in. In digital, a 
mediocre zoom is every bit as good (actually better) than a prime Leica 
lens. So with the zoom and nothing else interchangeable, the dust problem 
doesn't exist. This week I'm going to look inside the big Nikon & Canon SLR 
digital cameras and personally see what they have in between the rear of 
the lens and the sensor. I know there is a frequency cutoff filter to dumb 
down the lens, but I'll bet they have a sealed barrier to keep dust off of 
the CCD. And if it were far enough away from the CCD, any dust on it would 
not be in focus. Like a dusty rear lens element.

Digital sensors are electronic. Trillions times trillions of electrons 
passing through it all of the time. This creates a charge in the glass 
cover, albeit small. But enough to attract dust. Like the face of your 
computer monitor. It's like trying to print statically charged negatives in 
your enlarger. An impossible task.

Sealing up a digital camera is actually the only way to keep it hassle 
free. LF & MF backs do have covers and require cleaning/dusting before use 
unless the print size is only going to be happy snaps.

Those of you that use (or have used) LF know the PITA it is to keep holders 
clean and dust free. Even after cleaning, you still have to load them and 
quickly store them inside a dustproof bag. I use static free plastic bags. 
And when you pull the dark slide to take a photograph, static can be 
created, especially with the plastic holders. This is why I use Quickloads 
and Readyloads, and the only other film holders that I use are made of wood 
(old Graphic holders) or metal (Grafmatic).

My Sharper Image Quadrasomething electronic air cleaner provides me with a 
completely dust and static free darkroom. What a joy!!!

Jim

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