BPP with various length images

[Mick G]

I am trying to stack images of M42 that are of different lengths to get detail in both the bright center section and the faint outer areas.  I am using the Batchpreprocessing script.  I have entered all my Lights (5 sec., 15 sec., 45 sec., 90 sec., 180 sec., 300 sec. and 480 sec.), Darks of the same times and flats.  I set the exposure tolerance for darks at 8 sec.  For image registration I used auto and for image integration I used Average and Percent Clipping (I had only 5 images at each time interval or I would have used Windsorized sigma clipping with over 8 images).  I ran the script and it created a dark master for each time interval, a flat master and one light.  Am I correct in assuming that the darks and lights of each interval were stacked separately and then combined to create the one light which I should now process?  Secondly, is this the best way to handle various length exposures?

I'm a relative beginner so be kind.

Thanks

Mick

[pfile]

i can't comment on the BPP questions, but with M42 it's pretty common to use the HDRComposition process on multiple stacks of varying length exposures.

rob

[Mick G]

So the desired method is to stack the lights, darks and flats for each time interval in BPP , then put the light from each combination in HDR Combination?

[bitli]

I cannot comment for the HDR part  , but BPP will stack all your light together, as I understand it (it only takes care of separating lights for different binning).  You can check the log (always a good idea).

Indeed, using BPP, you should probably handle the different times separately (also check that BPP did the right things to your flats). You may want to first handle just two durations, check the log to make sure it is OK, check that you understand how HDR works, and only then do the work with all durations.  This may be easier to find the right process.

-- bitli

[vicent_peris]

Hi,

Yes, run BPP with each exposure time data set and then mix all together in HDRComposition. In BPP, you'll need only to reconfigure the light file list, as your calibration frames will be the same for each data set.


Best regards,
Vicent.