are non digital lenses better for digital slrs?

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Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital (More info?)

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?

 

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Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital (More info?)

Lenses that are soft at the corners or tend to vignette at wider apertures
will seem better because of the smaller sensor. But a lens that is a dog in
terms of sharpness and contrast, for example every 28-200/300 zoom by every
manufacturer, is still going to be an unsharp and low contrast dog with
better looking corners.

 

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Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital (More info?)

Luis ORTEGA writes:

> 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?

An article this month in the French camera magazine _Chasseur d'Images_
appears to support this. Since the 35mm lenses must cover a larger
area, the small area used by most digital sensors does not extend into
the margins of the image area where lens defects are most obvious. In
side-by-side tests of several "digital" and "non-digital" lenses, the
non-digital lenses did better overall.

Of course, this has nothing really to do with whether a lens is
"digital" or not; it's simply a consequence of designing one lens to
cover a larger area and then using only the central portion of the image
field. For full-frame DSLRs, this question is moot, as their image
areas are the same as those of 35mm film cameras.

--
Transpose hotmail and mxsmanic in my e-mail address to reach me directly.

 

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Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital (More info?)

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.)

>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?
>

*******************************************************

Sometimes in a workplace you find snot on the wall of
the toilet cubicles. You feel "What sort of twisted
child would do this?"....the internet seems full of
them. It's very sad

 

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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"

 

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Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital (More info?)

Kibo informs me that Old Nick <nsnfwhite@iinet.net.au> stated that:

>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.

No, that's not correct. Any sensor that is smaller than a 35mm frame
only sees the central portion. And yes, this does have advantages with
35mm-system lenses that suffer from edge softness / distortion /
vignetting.

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------

 

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Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital (More info?)

On Mon, 24 May 2004 16:49:14 +1000, Lionel <nop@alt.net> vaguely
proposed a theory
.......and in reply I say!:
remove ns from my header address to reply via email

Yeah. When I thought about it, that's why you get greater
magnification from a smaller sensor and a given lens.

Sorry. Brain fart.


>>But IIRC, the sensor "sees' the whole lens no matter what size it is.
>
>No, that's not correct. Any sensor that is smaller than a 35mm frame
>only sees the central portion. And yes, this does have advantages with
>35mm-system lenses that suffer from edge softness / distortion /
>vignetting.

*******************************************************

Sometimes in a workplace you find snot on the wall of
the toilet cubicles. You feel "What sort of twisted
child would do this?"....the internet seems full of
them. It's very sad