From: Sevo Stille (Sevo_Stille@f.maus.de)
 Subject: Re: What is difference 1.4f and 1.8f ? 
 Newsgroups: rec.photo
 Date: 1994-07-20 09:34:13 PST 


in article <Ii_dN_KSMUYNIM3=Ni@transarc.com> Tanvir_Ahmed wrote:
>It will be like comparing apples to oranges, but I have recently read
>some literature on the Ziess N-Mirotar 210mm.  They use some kind of
>amplification (needs 2 1.5V AA batteries) and use mirror instead of a
>refracting lens but combination of both of these (amplification and fast
>mirror) give the lens a very high speed.  They claim the lens speed to
>be F0.03 (that is 11 times faster then f1.4).  I wonder how will it feel
>shooting with it at night (and wonder too what kind of image degradation
>because of processing).

The N-Mirotar is (or was) a mirror lens coupled to a cascaded CRT light
amplifier. The image is monochromatic green, with a extremely poor resolution
(like a prehistoric TV set). This may be ok for some army, police, and some
research purposes where you have to bring home your photo no matter how bad,
but it is hardly good for general photography.

Sevo