[Comm2011] Distorsion, crosstalk, tilt: outlook for OCAM 1B

[Konrad Kuijken]

I discussed OCAM1B briefly with Bernard last night.
We will try to measure the tilt now from focus runs in the coming  
days, and test it with shims during 1B. So we will have to measure the  
focus tilt again then, to look for (inevitable) sign errors.
I have an automatic script which analyses focus sequences over hte  
whole field automatically (no more clicking for 1.5 hours Ewout!)  
which seems to work; I'll take charge of these measurements and  
interact with VST on this.

Crosstalk is being worked on by Olaf - could be some poorly shielded  
cables somewhere. It only shows up with point source measurements,  
which we are not able to generate during the day (even a pinhole mask  
in the filter give very fat spots - nice camera obscura pictures of  
the primary actually!). So it needs nighttime observations. ODT is  
still there for almost a week and this is high on their list, together  
with the gain/saturation/linearity.

We think it would be great to have a few more nighttime astronomers on  
the mountain for 1B!
Please note Ewout modified the PSF anisotropy plot of qualitywise to  
have the line length reflect ellipticity size instead of FWHM. I think  
we can still tweak this some more.

Off to the airport.

Phew!

Koen


On Apr 1, 2011, at 12:47, Gijs Verdoes Kleijn wrote:

> Dear OCAM 1A commissioning team,
>
> We are of course very interested to hear the outcome of last nights  
> work on the distorsions (i.e., anisotropy of the PSF), cross-talk  
> and saturation. If you find the time in your busy schedule.
> Let us know where we can help out today with additional analysis. We  
> expect the data in this afternoon.
>
> Tilt and PSF anisotropy can have an effect on the OCAM 1B schedule.  
> What is the opinion on the mountain regarding this?
> Please let us know if can help there with further analysis.
>
> Best wishes, om behalf of the Groningen team,
> Gijs
>
> -- 
> --------------------------------------------------------------------
> |dr Gijs Verdoes Kleijn         |   astronomer                     |
> |e-mail: verdoes at astro.rug.nl   |   OmegaCEN / Kapteyn Institute / |
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