RE: I Camera Flatness

["Albertson, Chris" <CAlbertson@primeadvantage.com>]

I would assume any non-flatness caused by the optical design
would have radial symmetry.  One thing to do is to make a 
scatter plot.  One dot for each pixel.  Plot (ADU - mean)
vs. its radial distance from the center.  You would hope for
a straight line.  Maybe instead you get a curve of some type.


> -----Original Message-----
> From: Tom Droege [mailto:tdroege@veriomail.com]
> Sent: Thursday, March 29, 2001 12:31 PM
> To: tass@listserv.wwa.com
> Subject: Re: I Camera Flatness
> 
> 
> I thought to look at one more thing. Looking at a small box 
> near the center 
> of the image I got:
> 
> Mean 186, sigma 29
> 
> At the corner:
> 
> Mean -309, sigma 28.3
> 
> So the sigma in a small box is comparable to the sigma over the whole 
> image. To me, this means that the noise is swamping the 
> variations due to 
> the optics. At least it is of comparable magnitude.
> <SNIP>
>