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Proposal #141

Proposer (14093) Phil Sullivan (navillus@sonic.net) obscode: SPP
Assigned To(3663) Dirk Terrell
Date SubmittedJune 22, 2020
StatusAllocated
PriorityNormal
Proposal


The CHOICE photometry course instructors Ed Wiley (CCD1) and Phil Sullivan (CCD2) would like to use images from BSM_TX to be used by students who cannot provide their own images. Dave Cowall and Arne Henden have been part of the discussions.

This proposal is just for testing how the images are distributed. If these tests are successful I will submit a separate proposal for the use of BSM_TX images in the courses.

Test Images requested for CCD1:

1.) Dark frames. I don’t know how the BSM system handles the dark calibration, but for this test I think only a few would be needed (5-11 sub-frames), just enough to be sure the distributed darks can be combined by the students to make a master dark. Larger numbers of sub-frames would be requested for the actual course.

2.) Bias frames. …same as dark frames, 5 to 11.

3.) B and V flat sub frames for each filter, 5 to 11.

4.) Uncalibrated B and V images of NGC 7790. Three images each. The exposure times for the BSM_TX images of the cluster which Arne recently sent me would be fine (see below).

Test Images requested for CCD2:

Calibrated B and V images of NGC 7790. The exposures and numbers of images per filter are not critical for this test. The 7790 images I received from Arne used two 40 sec V’s and four 80 sec B’s.

One of the uses for these image will be for the class observing project. Some of the potential targets are relatively short period cepheids, so I’d like the test images to come daily for five or six days, or longer depending on weather, until a series of at least five or six nights of observations is reached.

I understand that all images will be available by FTP, but it would be very helpful if the requested image could also be shared in VPhot, CCD2 images shared with SPP, CCD1 images shared with WEY.

The 2021 CCD courses will be held in the fall, so there is plenty of time to make corrections and adjustments to these requests before they are needed.

Phil Sullivan

Targets
Target RA (H.HH) Dec (D.DD) Magnitude Telescope Observation Frequency Expiration Date Proprietary Term
NGC 7790 23.973333 61.20806 13.0–10.0 BSM_NH2 1 Dec. 21, 2020 No

Comments

(4726) Kenneth Menzies — June 24, 2020, 1:56 p.m.

Phil:

I looked at your proposal (#141). I asked this question before so I hope it is not just annoying.

Do you want the images available for your course OR do you want the final images taken during the course?

Since the courses will occur at a specific time and it is difficult to guarantee what the weather will be like, it is certainly easier to take the desired images as soon as possible, and place them in the Choice Course VPhot Image Archive and share them with the course instructors (SPP and WEY). They can then be shared by the instructors via VPhot to all the participants at the appropriate time.

This scheme also allows you both to check them out ahead of time and make sure they completely meet your needs. You can still take some images during the course (for show and tell) but do not have to worry about any problems.

It appears that the CCD1 participants will need the raw calibration images and uncalibrated NGC7790 images that the students will process and calibrate themselves. This is not how the AAVSONet system normally works. Only images completely processed (plate-solved/calibrated) in the HQ pipeline are automatically distributed to requestors. Therefore, this part of your proposal needs to be done outside the normal process.

For CCD2, the calibrated NGC7790 images can be automatically shared to the instructors in accordance with the normal AAVSONet process. Since you want to get images that give you a nice light curve for the cepheids, it is definitely worth getting those collected and placed into the image archive ahead of time to ensure that they give nice results.

Does this make sense? I keep wondering whether I’m missing something? Your proposal explains what images you need BUT especially for CCD1, an atypical process is necessary to get you the desired raw images.

Ken

PS: Arne, at the moment BSM_TX only includes BVRI filters, not UZsY.

(4726) Kenneth Menzies — June 24, 2020, 6:35 p.m.

P141 plan created and committed to BSM_TX. Set to run one night for SPP and WEY to check. Used BVRI filters x 4.

(14093) Phil Sullivan — June 24, 2020, 7:31 p.m.

Ken,
I just sent you an email which I think covers most of your questions. To clarify for CCD2, I don't want images collected well ahead of time; I want them hot off the pipeline but starting a week or two before the course starts.

At the top here, the "telescope" is shown as BSM_NH2. ...should be TSM_TX as shown in your last line here.
Phil

(14093) Phil Sullivan — June 24, 2020, 7:34 p.m.

"It appears that the CCD1 participants will need the raw calibration images and uncalibrated NGC7790 images that the students will process and calibrate themselves. This is not how the AAVSONet system normally works. Only images completely processed (plate-solved/calibrated) in the HQ pipeline are automatically distributed to requestors. Therefore, this part of your proposal needs to be done outside the normal process."

I think Dave and George have already worked this out.

Phil

Comments on this proposal are closed.