[Comm2011] Status

[Edwin A. Valentyn]

Dear all,

at first sight the setting described by Ewout looks quite ok.
The advantage of full dynamic range (saturation at 65000) is 
significant, while the increase in read noise is only marginal when 
compared to the few dozen poisson noise on a 300 sec dark sky.

regards
Edwin

On 29-4-2011 3:11, helmich wrote:
>
> Hi everyone,
>
> Part of this mail is covered in previous mails. The first day we have 
> spent mostly on gain, readnoise, quickcheck etc. meant to determine 
> the best FIERA/preamp settings. I think we have not reached an optimal 
> solution. Input from Groningen is appreciated: Olaf & co from ESO are 
> very eager to get this out of the way, and for us it is best as well 
> if we can settle on final settings now. With the FIERA filtering 
> changed and the preamp increased as well, we get saturation at ~65000 
> ADU. Gain is relatively high ~2.5e/ADU. Readnoise in ADU is ~2.0 ADU, 
> but in e is high ~5.0 e- (sometimes higher, and therefore slightly 
> outside specificiations).
>
> If we cannot accept this, then changes of hardware components are 
> necessary. Obviously, if we can be satisfied with the current setup 
> this is convenient.
>
> Yesterday was spent with us doing readnoise, quickcheck, bias, in the 
> morning while afterwards Olaf worked on the instrument. In the 
> afternoon Bernard & co arrived and they've been working on shimming. 
> This will continue today and Bernard estimates is finished this 
> evening at the earliest.
>
> Regards,
>
> Ewout
>
>
> _______________________________________________
> Comm2011 mailing list
> Comm2011 at astro-wise.org
> http://listman.astro-wise.org/mailman/listinfo/comm2011

-- 
-------------------------------------------------------------------------
Prof. Dr. Edwin A. Valentijn       University of Groningen
Coordinator Target                 www   : www.rug.nl/target
Head OmegaCEN                      www   : www.astro.rug.nl/omegacen
Kapteyn Astronomical Institute     tel   : +31 (0)50 3634011/4036 (secr)
P.O.Box 800                        mobile: +31 (0)6 48276416
NL-9700 AV Groningen               e-mail: valentyn at astro.rug.nl
The Netherlands                    www   : www.astro.rug.nl/~valentyn
-------------------------------------------------------------------------







-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://listman.astro-wise.org/pipermail/comm2011/attachments/20110429/87b36a79/attachment.html