Re: z-band images with fringes

From: Jean-Charles Cuillandre <jcc_at_cfht.hawaii.edu>
Date: Thu, 26 Apr 2007 18:09:06 -1000

 Hi Yannick,

I reprocessed 764797 and the residual is 3%, which looks just
really bad on the binned images. I have been looking at why
some files get defringed in a better way than others, and though
some trend can be derived, there are times of the night when
the sky (OH lines that is) really goes crazy and the master
flat for the run just does not work well (which is why badly
defringed images come in groups).

My plan for the refined defringing is to also come up with
an estimator of defringing quality. Passed a certain level,
I should have the file passed to a different method (more
labor intensive, as long as it consists of less than 5%
of the i' and z' frames).

Sorry for this taking so long, but the flat-field (grids)
is not yet clearly solved, better handling of fringing is
the top priority after that one.

                                        Jean-Charles.
>
>
> Dear Kanoa
>
> These files seems to have also a problem with fringe suppression:
>
> 764795
> 764796
> 764797
> 764798
> 764799
>
>
> Cheers
>
> yannick
Received on Thu Apr 26 2007 - 18:09:06 HST