WBPP processing of data from different epochs ?

[cwinkler]

Hi there, after having manually pre-processed my data for many years, I decided to "try" the WBPP script. First run was quite impressive. Based on my "manual processing" experience I'm having a question on WBPP, as it was my first experience with WBPP the question looks trivial, my apologies....:

How do I process with WBPP light frames which have been taken with the same filter but at two different epochs, each dataset has its own set of flat frames.? At the end I want one integrated linear pre-processed image ? During manual pre-processing I applied ImageCallibration on both data sets, and combined the calibrated lights later in StarAlignment and ImageItegration

 

[ngc1535]

Use grouping keywords.

and

-adam

 

[cwinkler]

Use grouping keywords.

and

-adam

Hi Adam,

Thanks for the link. I watched your video and was convinced I knew what to do. Sadly, it did not (completely) in my car. Perhaps you could look at it and let me know where the error is. Thanks in advance for your time.

So I created a test directory called WBPP_test and populated it with two subfolders called NGC6990_day1 and NGC6990_day2. Each subfolder day1/day2 has two subfolders Flats>Ha and Lights>Ha which in turn have one lights data set and one flats data set on day 1 of the NGC6990 observation, with H alpha Filter. (see attached screenshotA). When I load the directory WBPP_test, then 4 data files are correctly loaded, and I have used the keyword NGC6990 in WBPP. The problems however are (see screenshotB and screenshotC): (1) While the two flats are correctly grouped per day, the lights are not. (2) The FlatsTab does not contain any flats, the flats are shown in the lights tab. (3) The calibration tab shows the problem with the unsuccessful grouping. (3) I had already previously noted when I just wanted to load a set of lights into the LIGHTS tab, that no information about the filter was used, the FITS header does not contain any info on Filter. I had created a subfolder for H_alpha, called Ha but it was not recognized as such. That problem I could solve earlier by adding lights and flats using the option to add custom files where you indeed specify the file type and filter. But, sadly, this does not work in this case where I want to process multiple nights.

Greetings, Chris

 

[cwinkler]

Use grouping keywords.

and

-adam

... well.. updating my previous message: Renaming folders NGC6960_day1... into VEIL_day1... results in a proper split of data day 1 and day 2, using KEYWORD VEIL. This is good. But don't know why NGC6990 dit not work, may be because it is included in the file_name ? Further progress achieved by renaming subfolder Ha into FILTER_Ha Now that shows up nicely in the list of lights, using FILTER as Keyword. Remaining problem: the flats are distributed according to day1/day 2 but WBPP "sees" them as lights, not flats although I had used keyword = IMAGETYP. The flat filename itself has the string "light-flat" in it, because when I took the flats I wanted to experiment with the exposure. This only works with my camera if you choose "light", not "flat" which assigns some other exposure... So, I guess the remaining problem is how to tell WBPP that my flat frames are really flats ?

 

[cwinkler]

and... final update: modifying the IMAGTYP keyword in the FITS header (via the BatchFITSKeywordEdit Script) to "Flat" finally gives the desired result: files are grouped in flat and lights, into separate days and filter info is there.... Only, this would mean I have to apply that BatchFITSKeywordEdit Script to those flats which will got into WBPP. I am sure there is a more elegant way of doing it ? Cheers, Chris

 

[bulrichl]

I am sure there is a more elegant way of doing it ? Cheers

You can use the '+Flats' button to enforce that the selected frames are taken as flat frames.

In future it would be better to only use imagetypes 'light', 'dark' and 'flat' in the image acquisition software. This will result in the FITS keawords that WBPP expects, and WBPP will work correctly.

Bernd

 

[cwinkler]

Yes, I think I can indeed put "any" frames into flats tab via '+FLAT' but it does not work if they are part of the directory as input to multi-night processing. Or, do I miss something ?

 

[bulrichl]

I guess that additionally you would have to set the depencies related to flat frames in section 'Calibration Settings' manually instead of using 'Auto', for both flat frame calibration and light frame calibration. (Not tested, because I use my MasterDark and MasterFlat for longer periods.

Bernd