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Nick James
ParticipantThe nova is about 0.3 mag brighter tonight (July 20) than it was yesterday. My unfiltered photometry is around 0.4 mag brighter than V band since the nova is so red but the trend is pretty clear. Of the other novae around V1405 Cas is brightening again although still around a magnitude below its brightest and V1674 Her is very gradually fading after its initial rapid decline.
Nick James
ParticipantYes, it looks to be at the bottom of a cycle.
Nick James
ParticipantHere’s the field. I get it around mag 12 (unfiltered re Gaia G) and a position of 20:21:07.71 +29:14:08.9 (Gaia DR2).
Nick James
ParticipantMy last observation was on July 7.9 at 16.52. It’s in the BAA database. Richard Sargent also got some observations later that night at around 16.10. They are in the database too.
Nick James
ParticipantI have a ten year old APC UPS in my observatory and it is on permanently, but so is the observatory PC that it powers and a few other cameras and sensors. They are designed to be on permanently but, like all electrical things, don’t like getting damp.
Nick James
ParticipantDaryl – There are certainly a lot more trails on my images this summer compared to previous years. For imagers the way that you stack subframes can help to a certain extent. The animated GIF attached is the same frame stacked as average and as sigma clip. There are 5 satellite trails on this image, two bright ones and three faint. The sigma clip stack definitely suppresses the bright ones. Photometrically the two stacks are the same.
Nick James
ParticipantCBET 4977 has designated this nova as V1674 Her.
Nick James
ParticipantI’ve just measured it as 7.54 (2021 June 13 22:51) compared to 5.94 at this time last night. Both unfiltered ref to Gaia DR2 G so somewhere between V and R. That’s a fall of 1.6 mags in day. That’s pretty fast. I remember photographing V838 Her (George Alcock’s last nova) in 1991 but only getting it on one occasion since it faded so fast.
Nick James
ParticipantAnother bright nova! Here’s my image https://britastro.org/observations/observation.php?id=20210612_231222_b0ed29be83050b55. I’ve taken some 1s exposures too which I’ll measure later.
Nick James
ParticipantHere are my edited highlights from yeasterday: https://youtu.be/MoRfhjLTS8k. From Chelmsford I managed about 15 mins at the beginning and end but it was cloudy for the rest of the time.
Nick James
ParticipantI too have ordered a copy. Tom’s unsolicited email campaign is clearly working! I wonder if the plot includes a hero who drives his car at supersonic speeds but is shopped to the local feds by a trusted colleague?
Nick James
ParticipantGary. Aren’t you at the ground? I was looking forward to an eclipse drawing from the posh stand at Edgbaston.
Nick James
ParticipantVery cloudy in Chelmsford at the moment after a cloudless day yesterday. Weather satellite shows it clear at the moment up the east coast and in the North Sea and a few clear patches elsewhere. Fingers crossed for some breaks later.
Nick James
ParticipantThis is the link for my eclipse livestream on Thursday morning https://youtu.be/DtqzzB5xAF8. The forecast for here looks encouraging at the moment.
Nick James
ParticipantHere is a speeded up video of your flares from Chelmsford. I have lots of cheap IP cameras pointing in all directions recording video in a 7-day cycle so I still had this from Sunday morning. There is quite of lot of cloud but Altair is visible just left of centre and Delphinus is visible through the cloud. I’m around 37 miles SW of you as the crow flies so my flares were probably not as impressive as yours.
Nick James
ParticipantThis is the set-up I’m using for the live stream. It is a Megrez 72 FD refractor on a NEQ6 with an IP camera module which feeds video directly into OBS via a long PoE Ethernet cable and then on to Youtube. It’s the first time I’ve tried this and it was far too easy! Hopefully the weather will play ball on Thursday.
28 May 2021 at 9:34 pm in reply to: Introducing MetroPSF – a program for ensemble photometry #584272Nick James
ParticipantHere is an example file which gives the JD zero date: http://www.nickdjames.com/Transfers/ngc6888_n_solved.fit.gz
26 May 2021 at 10:26 pm in reply to: Introducing MetroPSF – a program for ensemble photometry #584265Nick James
ParticipantMax, Thanks. That works and this looks really powerful, particularly the ability to measure multiple variables in a field and generate automatic reports. My only remaining comment is that I get strange timestamps:
ES UMa, -4713-11-24 12:00:00.000 UTC, G = 10.91 ± 0.11
-4713 is something like JD = 0. The FITS file I’m measuring includes the record:
DATE-OBS= ‘2021-05-25T22:53:18’ / Start time of stacked exposure
Nick.
26 May 2021 at 7:25 pm in reply to: Introducing MetroPSF – a program for ensemble photometry #584263Nick James
ParticipantHi Max,
I’ve downloaded 0.15 and am running it under Windows 10. It does the PSF photometry but then fails when I try to download catalogue stars:
694 ‘charmap’ codec can’t encode character ‘u03b1’ in position 25: character maps to <undefined>
Any idea what this might be?
Nick.
Nick James
ParticipantMaxim,
Just to let you know that I’ve been using the program but haven’t had a chance to look at the SNR details yet. I’ll do that when I get time.
Nick.
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