The digital lens design is based on the Bathascopic design used mostly for submarine periscope lenses.
S.
----- Original Message ----- From: "Don Roberts" <droberts@xxxxxxxx>
To: "List for Photo/Imaging Educators - Professionals - Students" <photoforum@xxxxxxxxxxxxxxxxxxxxxx>
Sent: Sunday, January 30, 2005 5:22 PM
Subject: Re: Digital ISO; lens optimization)
Karl, I have been in photography for almost 50 years; I do understand the relationships of lens coverage to film size, image circles, circles of confusion etc. I had not read all of the earlier posts regarding this as I thought that they were repetitious of earlier discussions. I missed some pertinent points that Jeff made about digital lens design. It is being explained again and I am following the thread.
Don
karl shah-jenner wrote:
----- Original Message ----- From: "Don Roberts"
: Maybe I'm misunderstanding you but I use a Nikon AF-S DX Zoom-Nikkor : 12-24mm f/4G IF-ED and it will not cover the full 35mm frame. Is : this not a redesign for digital? Or is it an APS lens rebadged? : What of the other DX Nikkors?
well Don, I've used a few Nikkors in my days and I can tell you the 150mm
certainly doesn't cover my 8x10, nor do the 35mm lenses cover 4x5. my cine
lenses don't cover 35mm (except the 40-400, but that's a different story)
but the 35mm lenses comfortably cover the smaller format of cine. the 4x5
lenses cover 35mm and the 8x10 lenses easily cover the lot.
it's all about the size of the formats relative to the size of the image
circle, which frequently but not always, is affected to some extent by the
focal length.
k
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Don Roberts * Bittersweet Productions * Iowa City, IA
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Our lives begin to end the day we become silent about things that matter. --Rev. Martin Luther King, Jr.
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