Re: [APML] Rosette comparison (was New Rosette Mosaic)

[Aplanatic@aol.com]

Bobby, Rob:

Both images are superb!  My congratulations.

Bobby's has higher resolution.  Rob is at a disadvantage here due to his 24um pixel size.  I've done quite a bit of work with the modulation transfer function (MTF) of various films and CCD's and, to make a long story short, the MTF of a square array of pixels matches the MFT of TechPan scanned at 4000 dpi when the CCD has a pixel size of approximately 10 um square.  For PPF this occurs when the array is approximately 14 um square.  These results are approximate and depend on a lot of other things.

Rob's RC Cass shows significant turned down edge on one of the optics.  Probably the secondary.

-Dave-


> Here you go: 
> http://www.koyote.com/users/bobm/rosette2.htm
>  
> ----- Original Message ----- 
> From: Robert Gendler 
> 
> 
> This is easy
> to demonstrate if Bobby would post an image cropped like the one below
> of NGC 2244 at about 1000 x 1000 res. and a comparison can 
> be made.
> http://www.robgendlerastropics.com/RosettebigC.html
>  

--  APML Archives at <http://astro.umsystem.edu/apml/>  ---
             Unsubscribe at <majordomo@seds.org>