Grant Privett

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Viewing 20 posts - 401 through 420 (of 464 total)
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  • in reply to: GSO 16″ Ritchey-Chretien telescopes #578932
    Grant Privett
    Participant

    Its the original focuser.

    A Starlight H18 and a Starlight filter wheel.

    It didnt happen after we put some tension of the focuser. Besides which, we were fast slewing an awful lot, so the scope would go from near zenith to near horizon in just a couple of minutes.

    We just installed a C11 RASA instead. Can’t use filters but it has a much wider field of view.

    in reply to: GSO 16″ Ritchey-Chretien telescopes #578930
    Grant Privett
    Participant

    I’ve used a 10″ Altair RC quite a bit and found that once I got the tension in the focuser sorted out, focus seems to say pretty tight for several hours. We had a couple of instances where it changed abruptly during the night, but that was some time ago now and seemed to occur only with a heavy CCD.

    in reply to: Graves loss of signal #578909
    Grant Privett
    Participant

    I thought it was operated by a private company and processed by the military. Pretty difficult to make a high powered radar being turned off a secret, they aint exactly covert 🙂 

    Happy New Year

    in reply to: Graves loss of signal #578902
    Grant Privett
    Participant

    Thats a fun system. I wasnt aware of them.

    The GRAVES system may be 24/7 but you can imagine it might go down occasionally for cable maintenance or software updates. 

    Saw online a mention of an upgrade in 2015 but nothing more recent.

    Also came across an email address for someone in the French Airforce noted as a contact. I doubt if anyone will complain if you ask them. Ignoring you won’t cost them anything. 🙂 What do you lose?

    • French Air Force – Franck Schrottenloher   spatial.cdaoa@air.defense.gouv.fr

    When you are content that its working well, is there any chance you could give a talk on it to the Shropshire Astro Soc? They are always keen to hear what people in the county are up to!

    in reply to: Dew heater straps and shields #578860
    Grant Privett
    Participant

    I’ve not come across that company before. Prices seem reasonable/good.

    in reply to: Dew heater straps and shields #578858
    Grant Privett
    Participant

    The C11 RASA and C11 SCT come in at about 32kg, with CCD and filter wheel, call it 35kg. Allowing 50% margin,  ~50kg. Thats less than half the system rating of 109kg. Am hoping we are okay, though I would like to be able to slew at 1 deg/sec to keep up with things like the ISS. 

    A Planewave L600 would be nice but without a Lottery win…..

    in reply to: Dew heater straps and shields #578854
    Grant Privett
    Participant

    Will post something here once I have it. Its going to be a stupidly large field of view compared to the f8 Altair RC.

    From your picture you use a dome. Does that save you some of the dewing grief?

    in reply to: Dew heater straps and shields #578855
    Grant Privett
    Participant

    Have seen some C11 size heaters for £50 but it didnt quote the power…

    Useful webpage! Followed a link on that site and have asked them for a quote on the co-mounting bars.

    Grant Privett
    Participant

    You could buy a Celestron 14″ Rowe-Ackerman for that!

    Grant Privett
    Participant

    Dread to think what the price will be for that camera.

    in reply to: C/2017 U1 (PANSTARRS). An interstellar comet? #578790
    Grant Privett
    Participant

    Apparently, the light curve (if a uniform albedo is assumed) implies a length to width ratio of 6:1 or more which is pretty phenomenal. Theres also a spectral response similar to a Jovian Trojan but dissimilar to a  KBO. How does that form?

    Its name is something or other in Hawaiian. Cannot understand how an interstellar interloper plunging through the solar system and boasting a large aspect ratio has not ended up being called Rama – as fans of AC Clarke would know.

    Fascinating object. Shame it was at mag 23. But there are, allegedly, lots more around.

    in reply to: Well here it is – the new Obsy #578743
    Grant Privett
    Participant

    Love the fold in roof support.

    How much does the roof weigh? Is it difficult to get back into place at the end of the night?

    in reply to: Auroral light pollution #578728
    Grant Privett
    Participant

    How far north are you?

    Full cloud here 🙂

    in reply to: UK Location of best number of clear nights and seeing #578724
    Grant Privett
    Participant

    As i recall, the rainfall maps show Norfolk to be pretty dry and you’re a good way away from any big hills, so does anyone living out that way care to comment on the amount of fog and clear nights? 

    In Wiltshire, where I am, there do seem to be a few foggy days in the autumn and winter.

    in reply to: UK Location of best number of clear nights and seeing #578721
    Grant Privett
    Participant

    Did you get any charts we could see?

    in reply to: The Victorian Amateur Astronomer – Allan Chapman #578694
    Grant Privett
    Participant

    Nope. Link still doesnt work but the one from Robin does.

    Thanks.

    in reply to: Iron meteors #578689
    Grant Privett
    Participant

    Thanks. Thought that might be the case.

    As you say, you could do some smoothing but that reduces the temporal resolution. Alternatively, there is processing you could do to assess interline scaling factors, but you would need to do some calibration runs at exactly the same camera settings – perhaps using a non-tumbling satellite as a reference. 

    in reply to: The Victorian Amateur Astronomer – Allan Chapman #578688
    Grant Privett
    Participant

    Link did not work.

    in reply to: Iron meteors #578683
    Grant Privett
    Participant

    Meteors are not my area of study, but is this an interlaced camera?

    The saw pattern on the light curves was interesting.

    in reply to: Image of Crux #578664
    Grant Privett
    Participant

    Two colour and one monochrome image added. There must be lots of BAA members with better pictures though…. Nik?

Viewing 20 posts - 401 through 420 (of 464 total)