Grant Privett

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Viewing 20 posts - 161 through 180 (of 477 total)
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  • in reply to: NEQ6 and TheSkyX #585123
    Grant Privett
    Participant

    Is that the option on the bottom of the Automated Calibration > Setup page?

    in reply to: NEQ6 and TheSkyX #585121
    Grant Privett
    Participant

    Yep. Thats what I do

    Sychronising is awkward as I need to jog the scope using TheSkyX and last time it was a long way out. Perhaps after my right angled finder arrives….

    Will see what happens tonight. Looks clear!

    in reply to: Interesting handmade mini telescope optics #585119
    Grant Privett
    Participant

    Apparently, the American Optical Corp, made several analogous systems in the 60s for reconnaissance systems. Though theirs was 3″ aperture, 7″ long and ran at f/35.

    A friend, keen on cameras, pointed me at this… https://www.photo.net/discuss/threads/vivitar-series-1-600mm-f8-solid-catadioptric-telephoto-lens.5501861/ and said the bokeh put people off them.

    in reply to: NEQ6 and TheSkyX #585118
    Grant Privett
    Participant

    Yep. Courtesy of the great Pat Wallace. I see that the original Fortran code was being used for setting up a major professional observatory as recently as 2 years ago. I saw a presentation by him on the code once. Impressive piece of work.

    Will try doing 25 stars and then add more every night instead. Will also see how far I can reduce the exposure and repeats and still work. Would be good to get it down to 15mins. Though, better yet, for it not to forget the model..

    in reply to: NEQ6 and TheSkyX #585116
    Grant Privett
    Participant

    Will give that a go! Probably in a couple of nights time…

    Even done automatically a 36 point T-Point takes 30-45mins out of the night – especially with the moon around driving up the sky backgrounds.

    Thanks.

    in reply to: NEQ6 and TheSkyX #585114
    Grant Privett
    Participant

    No, I don’t. I assumed that, if it was delivering the star to near the field centre then the TPoint model was working fine and I didn’t need to do anything. 

    Is that an error on my part?

    Would be nice if it was as trivial as that.

    in reply to: Following JWST through Orion to L2 #585068
    Grant Privett
    Participant

    No clear night here in 2 weeks.

    I think the blog now says the starboard boom is out and the tensioning of the sunshield will begin.

    Your JWST mag report is very hopeful for getting images at L2.

    What mag was the rocket body? Can I assume that won’t reach even a semi-stable orbit and will quickly drift away? Might be an interesting observation target for a while.

    in reply to: Following JWST through Orion to L2 #585060
    Grant Privett
    Participant

    Same in Wiltshire. Impressed by the Highlands having 4 clear nights in the last week when we cannot manage 1.

    in reply to: Following JWST through Orion to L2 #585029
    Grant Privett
    Participant

    Nicely placed for observation from the UK then. I’m looking forward to imaging this.

    How far apart will it be from the vehicle that launched it?

    in reply to: Which webcam #584957
    Grant Privett
    Participant

    Lodestars are pretty good – 1st gen is probably good enough, as is the ZWO ASI120mm. I’m considering those for my camera to do a similar thing. Saw a second hand Lodestar today for £150 and the ASI is similarly priced. A significant part of the cost would be the lens on top… I will probably control mine via a Raspberry Pi.

    I’m sure other have better ideas though.

    in reply to: Solar Orbiter #584935
    Grant Privett
    Participant

    Oh, SOLO. That has saved some cursing on my part…. 

    Thank you!

    EDIT: the 56MPH winds forecast for here at the time kind of dampen enthusiasm….

    in reply to: Sky and Telescope Reborn? #584886
    Grant Privett
    Participant

    Apologies if my flippant cynicism inadvertently caused offence. It had not occurred to me I was making a political statement. I felt I was merely commenting on an aspect of modern day life familiar to many. Good products being tweaked to increase the profit margin and becoming less attractive to many. I would cite the frivolous example of a Mars Bar. The “New Improved”  iterations have made them smaller, always less substantial and always containing less chocolate solids. Same name, different product. 

    The S&T magazine was originally really very good indeed – many serious UK astronomers read it and I avidly consumed it when I returned to amateur astronomy in the early 90s.  I am proud to have had an article published in it. It was a great read. Something to look forward to. Then, someone else bought it.

    The reviews became less in depth, material of interest to non-beginners became less common, several good writers left and it became much, much, thinner. I certainly gave up my subscription as it diminished. From my viewpoint it became not worth the money when it stopped serving the whole community.

    I am delighted to hear S&T is thriving again and that de Cicco et al are still doing good work. If I ever come across a copy I shall give it a go.

    But, for future reference: what would be an acceptable non-political phrase to refer to the people who, from my viewpoint, ruined a quality product?  

    in reply to: Projects #584866
    Grant Privett
    Participant

    The 4″ Unistellar you are currently using is quite capable of making useful observations. I am currently using a 4″ Skywatcher Newt to look at variable stars and started submitting results – after a 30 year gap. Working out the magnitudes of the stars is something fun to do on the numerous cloudy nights. 

    The instrumentation bar to participation in useful observing is very low. A pair of binoculars and a notebook can be a good starting point.

    in reply to: Projects #584855
    Grant Privett
    Participant

    I would just note that the second paragraph of the website’s About Us webpage makes a big thing about the society encouraging useful observation:

    “Since the beginning the BAA has encouraged amateurs to make scientifically valuable observations, often in collaboration with professional colleagues.”

    I am a deep sky observer and so far from against taking the occasional “pretty pictures” as my personal Album testifies – IC342 for example. But, apart from as training exercises, what would astronomy gain from hundreds more images of the Messier Top Ten? What makes the BAA stand out from the vast majority of local societies is the degree to which it does encourage useful observation.

    On the subject of instruments I suggested a RASA and a C11 as a wide field and narrow field/filtered co-mounted straw man option, but 2x C11 could also work nicely if a spectroscopic option was supported (and would not strain a Paramount or 10 Micron) – I just figured planetary observing would probably be more widely supported than spectral.

    Will be interested to see what, if anything, transpires.

    Grant (a humble ordinary member) 🙂

    in reply to: Flaring of synchronous satellites from Kelling Heath #584847
    Grant Privett
    Participant

    I think its more to do with the angle the solar panels are being maintained at.

    I was impressed enough with them making naked-eye visibility. 🙂

    in reply to: Flaring of synchronous satellites from Kelling Heath #584845
    Grant Privett
    Participant

    Flares happen petty much every night (if the satellite isn’t eclipsed by the Earth). I have certainly recorded some as mag 5.

    Worth noting that, depending on their stance, they may not flare when they are nearest the antisolar point, but up to 45 minutes earlier or later. I recorded one flare 3 hours later than antisolar – but that satellite was thrusting at the time.

    in reply to: Projects #584844
    Grant Privett
    Participant

    Alternatively, how about setting up a scope at a hosted site and giving each section nights in turn so the VSS can go through dozens of VS a night, the comet section can do all comets visible from site and greater than mag 18, the Asteroid section could chase low phase angles and some compromise reached to allow good amounts of planetary observing at the most favourable point of the nights. You could cover a lot with a Paramount and co-mounted C11 and 11″ RASAs.  

    A simple criteria: data collected must lead to papers or it doesn’t get collected.

    in reply to: Dual Scope Mounting #584805
    Grant Privett
    Participant

    The RASA comes with a mounting bar along the top…

    in reply to: Dual Scope Mounting #584790
    Grant Privett
    Participant

    I use a 114mm Newtonian riding piggyback on the back of an 11″ RASA V1 mounted on a Paramount MEII. So, way within the mount weight limit. Seems to work very well (the 114mm is used as a autoguiding scope), but I could envisage trouble if it wasn’t being used in a roll off roof shed – as the slit of most domes would be too narrow.  

    in reply to: LL And rare outburst #584776
    Grant Privett
    Participant

     While between OTAs, I have been using my 114mm guidescope and an unfiltered Lodestar to occasionally take some measurements of LL And. Because they were mainly taken on moonlit or partially cloudy nights (and I am a deep sky observer) I just let the camera run a series of 30s frames in the hope it might drive down the errors that would be present with such a small light grasp instrument. Its not the best way to do this sort of thing, but it was simple to do and fun.

    To analyse the data, I wrote Python code to plate solve all the frames, locate all the stars, compare the catalogue stars to those on my frames, established the Zp for each frame and thus derive the mag of LL And. I then took the median result (mag1).

    To make things more interesting, I also looked at 4 comparison stars from the AAVSO chart and derived mags (mag2) for those using the sums of the fluxes measured from all the frames. I may extend the number of comparison stars.

    The results are these:

    Date      Mag1   Mag2   Magerr  Frames

    210917  13.15   13.32    0.15      122

    210918  13.39   13.60    0.4        212

    210921  13.71   13.90    0.25      307

    210922  13.77   13.98    0.25      277

    210929  14.58   14.71    0.35      156

    211010  17.41   17.26    0.8        179

    Usable results could have been obtained with far fewer frames, but I had hoped to see some evidence of superhump activity (yeah I know) so I just let it run.   

    What I am noticing from this – apart from how interesting LL And is – is that the Mag1 value seems consistently brighter than the Mag2 value. I won’t be submitting any observations formally until I figure out what causes that. Has anyone any thoughts on what I might be doing wrong?

    EDIT: Andy worked out the problem and I am ashamed that I didn’t myself. One approach used the Gaia g catalogue mag values and the other used the AAVSO sequence mags ie V.

Viewing 20 posts - 161 through 180 (of 477 total)