Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital (
More info?)
On Mon, 24 May 2004 14:36:26 +0800, Old Nick <nsnfwhite@iinet.net.au>
wrote:
>On Sun, 23 May 2004 00:51:00 +0100, "Luis ORTEGA"
><lortega@ntlworld.com> vaguely proposed a theory
>......and in reply I say!:
> remove ns from my header address to reply via email
>
>I am masking elsewhere about this to refresh my brain.
>
>But IIRC, the sensor "sees' the whole lens no matter what size it is.
>So edgew softness would still be an issue. In fact as one other poster
>said, because of the smaller sensor, a lot of "good" 35mm camera
>lenses will not come up to scratch.
>
>One possible advantage of using a larger lens is that you can stop the
>lens way down and still have a lot of light coming in, compared to the
>smaller "digital" lenses. _This_ would get rid of edge softness, as
>the iris provides greater depth of field and starts to occlude the
>lens edges. (??? again I am thinking about this. rusty.)
The lens (in the case of 35mm cameras) puts an image on the focal
plane that is large enough to cover the 35mm film frame. It has to.
In DSLRs using lenses for 35mm cameras, the lenses still put that same
size image on the focal plane, but (unless it's a 'full size' sensor)
the sensor is smaller than a 35mm frame, so some of that image from
the lens falls outside of the sensor.
You can go here; this page shows a representation of the different
sizes of sensors, and how they compare to a 35mm film frame:
http://www.dpreview.com/reviews/olympuse1/
Using the term "large(r) lens" is confusing; does "larger" refer to
focal length, f-stop, 4X5 vs 35mm?
>
>>My understanding is that since a digital slr sensor is smaller than the area
>>of a 35mm negative on some digital slrs (say the nikon d70), then using a
>>lens designed for a film slr would tend to produce a better image since most
>>lenses are best in the central part of their image area and that is the part
>>of the image that would be captured on the digital sensor.
>>does this theory make sense, or is it correct?
--
Bill Funk
replace "g" with "a"