[KIDS] QC FRINGES: ReducedScienceFrames invalidated due to improved defringing

[Hugo Buddelmeijer]

Dear KiDS team,

An errata to yesterdays mail: only bad FringeFrames have been 
invalidated, always with a comment (and subsequently remade). 
ReducedScienceFrames using bad FringeFrames are /not/ invalidated.

Some ReducedScienceFrames (mainly of chip 89) are invalidated due to 
residual fringe detection that is done independently from the checks on 
the FringeFrames.

Greetings,
Hugo Buddelmeijer.


On 03/05/2012 12:10 PM, Hugo Buddelmeijer wrote:
> Dear KiDS team,
>
> Some positive notes about the defringing:
> * The experimental residual fringe detection algorithm works well:
> it detected several ReducedScienceFrames with residual fringes [2].
> * The worst of these (almost all) were accidentally defringed with
> the 'old' defringing method, using old FringeFrames.
> * Therefore, we can conclude that the new defringing algorithm
> (introduced late January [1]) works quite well when used.
> * The bad ReducedScienceFrames (25 tiles) have been invalidated and
> new FringeFrames are created for these nights.
>
> Some action items about defringing:
> * Observations that still have residual fringes after applying the
> new defringing method should be identified.
> * Both the defringing algorithm and the residual fringe detection
> algorithm are 'confused' by the presence of large ghosts and bars.
> * Detecting and flagging or correcting these artifacts seems to be
> the best way to improve the defringing. (Furthermore, these might
> cause larger errors in the photometry than the fringes do.)
> * The new FringeFrames can show a gradient in the amplitude of the
> fringes. It might be worthwhile to investigate whether this is
> physical.
>
> Greetings,
> Hugo Buddelmeijer
>
> [1]
> http://wiki.astro-wise.org/projects:kids:survey_task_teams:detector_calibration
>
> [2] http://wiki.astro-wise.org/people:hb:fringedetectionkids05