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Hi James,
Not the same camera but with my compact camera the video is downsampled from the native sensor resolution to the video resolution based on the width of the video frame and then if the aspect ratio of the video is different from that of the sensor, the video image is cropped in height. eg 5184×3456 would be downsampled to 1920×1280 and then cropped 100 pixels top and bottom to give 1920×1080. The downsampling ratio is not in general a whole number of pixels (ie a simple binning) so presumably it is done using some kind of interpolation algorithm to maintain image quality.
Cheers
RobinAn AAS research note has been issued discussing the similar short term flare event seen in amateur spectroscopic observations during November 2024
https://iopscience.iop.org/article/10.3847/2515-5172/adb425
(It is possible that these are common during the low state but may not be picked up due to observing cadence)Cheers
RobinThe Variable Star Section is a good example of why it can be useful to make a Circular public. I know that professional astronomers read it. If it were behind a pay wall then that might not happen. Having the professional researchers read the Circular benefits the members who contribute to the Section.
I’ve experienced this just today. It was an unexpected treat to see in a paper just published on the RW Cep “Great Dimming”
“Atmospheric dynamics of the hypergiant RW Cep during the Great Dimming”
https://arxiv.org/abs/2501.11701
several references to my BAAVSSC article on thisCheers
RobinAnd another paper
“Bridging the Gap: OPTICAM Reveals the Hidden Spin of the WZ Sge Star GOTO 065054.49+593624.51”
https://arxiv.org/abs/2501.11669
(Detection of a 148s periodic signal in high cadence photometry)Chrome win 10 here. I stay logged in to the BAA site if I close the tab but keep the browser open but it logs me out immediately when the browser is closed. Many websites/forums give the choice to be remembered or not (which IMO is the best arrangement) while with others (like Amazon for example and soon Outlook) you have to physically sign out unless you are using private browsing.
Preprint now on ArXiv
https://arxiv.org/abs/2501.11524
(Includes some of my spectra taken with ALPY200/600)Cheers
RobinFrom a practical point of view though it would greatly help if there was an option to stay logged in on the website. Trying to view or comment on something which is restricted to members only to have to log in and then be directed away from the page you were viewing is very frustrating.
There seems to be some inconsistency. For example VSSC, Comets Tale and Infinite Worlds are all open access while the I&E, Solar Section and Deep Sky Newsletters are members only. Is this at the discretion of the section director or is it due to where they are located within the website?
Not sure how much Registax has been updated/rewritten over the years but its origin dates back over 20 years now, predating multicore processors in PCs
Meanwhile the observatories around Paranal (including the yet to see first light ELT) face a potential threat from a US backed proposed green energy mega-project
https://skyandtelescope.org/astronomy-news/will-chilean-observatory-lose-its-dark-skiesRobin
In the meantime these systems are being used without oversight or basic checks that any observer should be doing. (The TNS system has no gatekeeper and relies on the accuracy of the submitted data). The issues with this observation are multiple and obvious without needing any further data to anyone with basic knowledge of how transients behave (A mag 14 object which suddenly appears with no sign of a precursor or host galaxy and then stays at identically the same brightness for several weeks should already have raised suspicions.) The ghost negative “missing star” in the (observed – archive) difference image and the double colour star images in the DSS 2 colour archive image of the region made it obvious was going on (even before taking into account the proper motion from Gaia and the 2MASS image showing it in yet another position) yet the operators of this system “followed” it for 4 weeks before finally triggering it as “discovery”.
Jack,
It looks like now you have got the badge off, you also now have to remove the plate underneath which is glued on. The chap here drilled it, screwed in a self tapping screw and pulled it off
https://www.cloudynights.com/topic/648277-disassembling-a-porta-ii/?p=9112803
Cheers
RobinThe rapid decline continues based on Atlas forced photometry
Attachments:
at the suggested 11Mpc distance could get much brighter
and then again perhaps not. After rising to mag 14.5 in just one day it is reported to be in rapid decline.
https://www.wis-tns.org/astronotes/astronote/2024-374
Now classified as an a relatively rare type IIb, a stripped envelope core collapse supernovaHas the BAA ever considered negotiating access for members to paywalled publications like this or is it just too costly/not feasible ?
Cheers
RobinCan you see the solar spectrum visually when the core module (without the camera objective lens) is held up to your eye and pointed at the sky? This will check that all is right with the spectrograph itself (slit/collimator/grism) If that is ok then with the objective lens in place you should then be able to focus the spectrum in the camera. Camera back focus is limited with the ALPY. Is the camera directly coupled to the spectrograph without an additional adapters ?
When you say you say you are moving the camera focus in and out, are you adjusting focus using the threaded tube and locking ring on the spectrograph body ?
A compact fluorescent lamp can help getting rough focus with the camera as the emission lines are more obvious than lines in the solar spectrumCheers
RobinThe overall significance is not clear, though there does appear to be a change in accretion environment and rate around October.
it looks like the increase in activity ended abruptly on 19th November. (A selection of Woody Sim’s spectra plus a couple of mine taken early morning showing He II 4686 emission line)
Cheers
RobinAttachments:
Like the comment there about it being green so it must be space junk as the guy who told him has a PhD in physics so must be right !
Here are the details based on UKMON cameras
Cheers
RobinThe details of this device are yet to be revealed though
Now officially launched.
https://www.sunscan.net/Cheers
RobinHere is the spectrum time series as a 2D greyscale plot with the intensities of three line extracted (qualitative only, no flux calibration)
I was surprised to find that it was only last year that hyperspectral techniques had first been applied to aurora
https://phys.org/news/2024-08-full-d-spectral-image-aurora.htmlCheers
RobinAttachments:
