From: Steve Shapiro (sgshiya@redshift.com)
Date: 12/03/02-02:30:21 PM Z
Below, it sounds like split developmet, to me :)
S
----- Original Message -----
From: "nze christian" <christian_nze@hotmail.com>
To: <alt-photo-process-l@skyway.usask.ca>
Sent: Monday, December 02, 2002 1:55 PM
Subject: Re: Scanning for greater dynamic range
> Ken,
>
> I used to work with multiple scan when I made confocal microscopy. The
> system is about the same as in astronmy but the pmt are a little
different.
> But the software I woprk with,(made by Leica) use an average system to
avoid
> noise. even with 2 scan it can give a better result. Sure the fact is it
> work best for low value, to avoid noise in the black.
>
> In microscoopy I used to scan first the blue then the green and last the
> red. each with a pmt only sensitive to this color with filters to avoid
> the avoer color to pass.
>
> Amicalement
>
> Nzé Christian
> mailto:christian_nze@hotmail.com
> http://www.c-nze.com
>
>
>
>
>
> >
> >
> >----- Original Message -----
> >From: "nze christian" <christian_nze@hotmail.com>
> >To: <alt-photo-process-l@skyway.usask.ca>
> >Sent: Monday, December 02, 2002 12:20 PM
> >Subject: Re: Scanning for greater dynamic range
> >
> >
> > > Hi,
> > >
> > > The double scan result in a better , because the 2 scans will be
> >different;
> > > the noise will not happen on the same point. The sofware will do an
> >average
> > > which mean that when the scan give the same result for a point, the
> >software
> > > let them like they are but when it give different result it will make
> >the
> > > average of the to point. this method is used in microscopy ofr
astronomy
> > > where single pmt are used. They often average to 8 or 16 which mean
that
> > > they scan 8 16 to avoid noise. a point should always give the same
> >result
> > > on the 8 scan, if not it apply a function or delete the point
> >considered
> >as
> > > pure noise.
> > >
> > > In our case the noise just come from the receptor, as there is no
change
> >in
> > > the light and in the photo. so this way to work avoid to many machine
> >noise.
> > >
> > >
> > > <If you double scan you still have the same signal to noise ratio,
> > > <therefore
> > > <no increase in dynamic range because you are just summing together to
> > > <scans
> > > <with the same signal to noise ratio. Unless you have software that
can
> > > <detect noise and remove it one is just fooling self. As far as I
know
> > > <this does not exist.
> > >
> > > Amicalement
> > >
> > > Nzé Christian
> > > mailto:christian_nze@hotmail.com
> > > http://www.c-nze.com
> > >
> > >
> > > > >
> > >
> > >
> > > _________________________________________________________________
> > > MSN Messenger : discutez en direct avec vos amis !
> > > http://www.msn.fr/msger/default.asp
> > >
> > >
>
>
> _________________________________________________________________
> MSN Search, le moteur de recherche qui pense comme vous !
> http://search.msn.fr/worldwide.asp
>
This archive was generated by hypermail 2.1.5 : 01/31/03-09:31:25 AM Z CST