Re: [APML] New All Sky Camera Images

[Gene Horr <genehorr@texas.net>]

Aplanatic@aol.com wrote:

> In general, the f/ratio of the system is increased from that of the camera lens by
> the following factor:
> 
> (1 + 2d/R)
> 
> where R is the radius of the sphere and d is the distance from the camera lens to the
> nearest point on the sphere.

Maybe my brain is drained from work this week, but something doesn't seem 
right about this.  Shouldn't the f/ratio be decreasing as you are effectively
shortening the focal length (assuming that the sphere covers the full effective
aperture of the lens in use, no adjustment for reflectivity, etc.)?

Gene Horr
genehorr@texas.net

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