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Recent AAVSOnet images

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HQA
HQA's picture
Recent AAVSOnet images

John Martin asked about recent BSM images, but since there are a couple of problems that affect all AAVSOnet systems, I decided to break it out as a new thread.

The processing computer (occam) was upgraded from Ubuntu 14 to Ubuntu 16 on Wednesday, when the patches for Meltdown and Sceptre were applied.  Unfortunately, this broke IRAF, which then was re-installed, upgrading from V2.14 to V2.16.

The combination of these two changes have caused some processing problems.  The main one currently is that the flat normalization task does not work, so flats have their original values (say, 33K counts) rather than the near-1.0 values after normalization.  This means images divided by the flats now have values that are scaled by 33K rather than 1.0, and so the small values, while legitimate FITS, may be difficult to process by some programs.

We will be reprocessing the images that were run through the pipeline since the software upgrades, once we figure out how to get the normflat task running properly.  This may take a week or so, as there are other timely demands.

In the meantime, George Silvis has disabled automatic image processing, so you will see no new images in your vphot or ftp accounts until the problem is solved.

Sorry for the inconvenience!

Arne

wel
wel's picture
It looks like the

It looks like the interpretation of the default image section region in the task is no longer working. I was able to specify the entire image as the statistics section to be used - which was what the default was supposed to do - and it worked as expected.

Cheeers,
Doug

uis01
Thanks for tracking it down

Thanks for tracking it down Doug.

The dam has broken and I'm now swimming in BSM data.

mrv
mrv's picture
Re: Recent AAVSOnet images

Arne, If the problem with IRAF hasn't been solved yet, I would be willing to manually calibrate my own images from SRO or OC61. I would just need someone to upload the raw science and calibration frames to my AAVSO FTP folder. Thanks, Bob

mrv
mrv's picture
Re: Recent AAVSOnet images

Thanks to AAVSO staff for getting automatic processing working again. Images from SRO look great, with normal background values. So, the flat field normalization is working correctly. Most of the OC61 images have normal background values as well. However, the V frames from OC61 for 1-30 and 2-3 have abnormally low pixel values. Sky background on these images is a small fraction of zero and even bright stars have peak values of only 1 or 2 ADU. This should be looked into. The B frames from these nights are fine. Also, the focus on OC61 has been rather bad during late January and early February. The telescope operator should be informed of this. Thanks, Bob

mrv
mrv's picture
Re: Recent AAVSOnet images

With regard to my message this morning, I've now received additional OC61 images for 2-6, 2-7 and 2-8. All V frames show the normalization problem and the B frames now as well. Focus is better on some frames, but a few are very out of focus (FWHM ~10-15 pixels). Thanks, Bob

HQA
HQA's picture
OC61 images

Hi Bob,

For some reason, the OC61 data reprocessing is still not correct.  Give us a few days to find the bug and redo them (I've been out of town).  I think all other AAVSOnet systems are being processed correctly at this time.  Sorry!

Arne

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