Path: utzoo!utgpu!watmath!att!tut.cis.ohio-state.edu!cs.utexas.edu!sun-barr!newstop!east!tjp!jpainter
From: jpainter@tjp.East.Sun.COM (John Painter - Sun BOS Hardware)
Newsgroups: sci.space.shuttle
Subject: Re: Hubble Space Telescope
Message-ID: <636@east.East.Sun.COM>
Date: 26 Jul 89 22:04:15 GMT
References: <2217@ccncsu.ColoState.EDU> <1136@noao.UUCP> <1405@ncrcce.StPaul.NCR.COM>
Sender: news@east.East.Sun.COM
Reply-To: jpainter@tjp.East.Sun.COM (John Painter - Sun BOS Hardware)
Organization: Sun Microsystems, Billerica MA
Lines: 14

In article <1405@ncrcce.StPaul.NCR.COM> johnson@ncrcce.StPaul.NCR.COM (Wayne D. T. Johnson) writes:
>In article <1136@noao.UUCP> groves@noao.edu (Lee Groves) writes:
>>Believe it or not, I have seen a chip with  < 10 photon per ADU sensitivity!
>>(ADU = Analog to Digital Unit.)
>>
>But how do you mesure < 10 photons?
>-- 

If a cascade photo-multiplier tube can register ONE photon, I imagine
a solid state equivalent could be had.  (but then you didn`t ask for
a solid state solution)

/Tjp
- signature withheld pend investigation