[Comm2011] twilights at different rotator angles

[Edwin A. Valentyn]

it would be easier to interpret the ratios of dome to sky at 4 angles.
Edwin

On 8-6-2011 5:12, Gijs Verdoes Kleijn wrote:
> Hi John and Edwin,
>
> As a quick check I have divided the raw twilights at different rotator
> angles by the one at rotangle=0: see top of this page:
> http://wiki.astro-wise.org/projects:omegacam:commissioning:flatfields
> ~2-3% differences in twilightflats as a function of rotator angle are seen.
>
> I think another analysis route is needed to say more than this about
> dependence on rotator angle. My first thought is to look again at
> twilightflats*gain
>
> Best wishes, Gijs
>
>

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Prof. Dr. Edwin A. Valentijn       University of Groningen
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