Archived posting to the Leica Users Group, 2005/03/17

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Subject: [Leica] Digital cameras with large aperture lenses
From: dorysrus at mindspring.com (Don Dory)
Date: Thu Mar 17 04:33:11 2005

Adam,
Two mutually reinforcing actions are going on to make large aperture
lenses vignette on digital sensors.  The first is the same as on wide
angle lenses; light rays from the edge of the lens are striking the CCD
at a relatively high angle and thus lost on the edge CCD's.  The second
is that a micro lens by nature focuses the light to a point, however, if
the light ray is striking the micro lens at a sufficient angle, the
focus of the micro lens is not on the underlying CCD.

Don
dorysrus@mindspring.com

-----Original Message-----
From: lug-bounces+dorysrus=mindspring.com@leica-users.org
[mailto:lug-bounces+dorysrus=mindspring.com@leica-users.org] On Behalf
Of Adam Bridge
Sent: Thursday, March 17, 2005 1:50 AM
To: Leica Users Group
Subject: Re: [Leica] Digital cameras with large aperture lenses

I don't understand how a microlens affects the full aperture
performance of a lens. More light is more light isn't it? So how would
this work?

Adam


On Tue, 15 Mar 2005 14:39:16 -0800, Henning Wulff
<henningw@archiphoto.com> wrote:
> Regarding the recent discussion about fast lenses not having linear
> response re: their f/stops, and acting like slower lenses, here is a
> recent discussion on dpreview on the issue. Conclusions are similar
> to the ones voiced here.
> 
> http://forums.dpreview.com/forums/read.asp?forum=1029&message=12649209
> 
> --
>     *            Henning J. Wulff
>    /|\      Wulff Photography & Design
>   /###\   mailto:henningw@archiphoto.com
>   |[ ]|     http://www.archiphoto.com
> _______________________________________________
> Leica Users Group.
> See http://leica-users.org/mailman/listinfo/lug for more information
>
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Replies: Reply from s.jessurun95 at chello.nl (animal) ([Leica] Digital cameras with large aperture lenses)
In reply to: Message from abridge at gmail.com (Adam Bridge) ([Leica] Digital cameras with large aperture lenses)