Olympus-OM
[Top] [All Lists]

Re: [OM] 200/4 vs. 2X-A (Was 100/2 vs. 85/2 in sharpness)

Subject: Re: [OM] 200/4 vs. 2X-A (Was 100/2 vs. 85/2 in sharpness)
From: Donald Shedrick <shedridc@xxxxxxxxx>
Date: Sun, 15 Jul 2001 11:51:11 -0700 (PDT)
Yes, the sun and moon are the same apparent size as
viewed from earth, but your formula for the image size
in a 35mm camera is high by about a factor of 2.  The
correct formula for the image size in mm is the focal
length in mm divided by 109.

Image Size of Sun (mm) = focal length (mm) / 109

A 400 mm flocal length has an image size of 3.7 mm and
a field of view of 3.4 deg x 5.1 deg.
See the web site referenced in my previous post.

--- frieder.faig@xxxxxxxxxxxxxxxxxxxxxxxxx wrote:
> On Thu, Jul 12, 2001 at 05:01:59PM -0500, gries
> wrote:
> > How large was the sun in the viewfinder?
> > 
> 
> 
> Rule over the thump: 
> a) Sun and moon aper in the same visible size. (this
> is  why moon an solar eclipe work).
> 
> b) With a 50 mm lens (shot taken on earth)  both
> have 1mm size in the negative.
> 400mm is 8x magnification, so they are have 8 mm
> size, wich is 1/3 of the picture
> height of OM cameras. 
> 
> Frieder Faig
> 


__________________________________________________
Do You Yahoo!?
Get personalized email addresses from Yahoo! Mail
http://personal.mail.yahoo.com/

< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >


<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz