Paul Leyland

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  • in reply to: An old brass refractor. #611251
    Paul Leyland
    Participant

    Alan, please do!

    Paul

    in reply to: An old brass refractor. #611248
    Paul Leyland
    Participant

    Now to track down the Patent number …

    I have not yet found the patent in the WIPO database but this link turned up

    https://www.grelly.uk/itm/genuine-27-inch-antique-w-ottway-1917-gunsighting-ships-navy-marine-telescope-142854086185

    Looks like my telescope may well be from the Royal Navy. If so, it would be nice to find out which ship to which it was fitted.

    in reply to: An old brass refractor. #611247
    Paul Leyland
    Participant

    Hi Paul & Alan,

    I will be restoring it though it may take me some time to clean and remount it.

    There are a few inscriptions, the easiest to read being “TURN TO CHANGE POWER” and “TURN TO FOCUS”. Part of the latter is visible in the image above. Neither of these give much clue to the provenance.

    You are quite correct at suggesting Ottway & Co. however, It is fairly easy to read, though the black paint needs renovation, “GUNSIGHTING PATENT V.P. <illegible> W. OTTWAY & CO. LTD EALING 1912”. Another inscription is “PATT. G328Y” and a series of numbers “5 7 9 11 13 15” which are undoubtedly the magnifications available. The only other inscription is “W A/T” where the W is twice the height of the A and the T, which themselves are spaced vertically with a horizontal bar.

    It is possible than <illegible> may become readable with some careful photography under oblique lighting and with image processing of the result.

    Now to track down the Patent number …

    in reply to: Discussions #611241
    Paul Leyland
    Participant

    It is possible some prefer not being left logged in permanently

    On some fora I frequent it is possible to remain log in and and also possible to tell the browser not to save the credentials. That would appear to satisfy both camps.

    in reply to: Discussions #611240
    Paul Leyland
    Participant

    Sorry, always have something more to say after I hit the “Send” button (and there’s no “Edit” anymore for some reason).

    Yes, this is something else I would like to see. It is possible to edit for a short while after submission but quite a few times the edit functionality times out to early for my liking. It would appear I am not alone.

    Could the period be extended to, say, 24 hours?

    in reply to: Discussions #611234
    Paul Leyland
    Participant

    Seconded, though it affects me a little less because I tend to leave the tab open 24/7. That’s feasible on a desktop machine in a private home.

    in reply to: Discussions #611223
    Paul Leyland
    Participant

    Hi Dominic

    I’ve mentioned this before but it bears repeating. As this text is being entered I am helpfully informed You can use BBCodes to format your content.

    There is no indication what BBCodes are, nor any obvious way of using them.
    IWBNI we could have a few buttons which, when pressed, underlined the selected text, inserted a hyperlink and so on.

    As you can see, I have memorized a few of them …

    Added in edit: even then, I was unable to work out how to use the [ URL ] tag properly.

    • This reply was modified 1 day, 22 hours ago by Paul Leyland.
    • This reply was modified 1 day, 22 hours ago by Paul Leyland.
    • This reply was modified 1 day, 22 hours ago by Paul Leyland.
    in reply to: CG Dra: a VSS campaign #611196
    Paul Leyland
    Participant

    You’re welcome.

    Now wondering if that sort of very detailed TS photometry could be used to predict the time of an imminent outburst perhaps to within a few hours. I doubt many people have tried to do it before.

    in reply to: CG Dra: a VSS campaign #611180
    Paul Leyland
    Participant

    Eclipses No(s): 27, 28
    State: Quiescent
    Data Quality: Good (check star sigma = 0.045)

    Holy cow. What’s going on here? I thought there was something wrong with my telescope.

    How do you measure the bright spot here? I assume the quiescence is somewhere in the middle of the chart, at 16.89 mag, and the bright spot before the second eclipse pushes it all the way up to 16.75 mag – an amplitude of 0.14 mag. Note two-step increase in brightness in the orbital hump – first to 16.85 mag, then the second one to 16.89 mag.

    The profile is a new type, U/H/A, never seen before. It is similar to U/L/S, except that here we see a very prominent bright spot.

    Lots of flickering – at the bright spot apperance, orbital hump, at the minimum, and the egress. Note the post-egress 0.05 mag dip, then sudden rise of 0.1 mag, then ~ 0.5 mag dip. Flickering? I don’t think so. Exactly the same structure is visible in both eclipses tonight. Is this the second bright spot or, perhaps, stream overflow? Could the second bright spot/stream explain the 2-step rise, and the post-egress hump?

    LOTS of questions.

    Max

    I have been following this thread with interest and the quoted post, expressing a degree of incomprehension over the star’s behaviour, prompted me to contact an old friend, Phil Charles. Phil is a notionally retired but still very active professional astronomer who has specialized in the study of CVs of various types. He has given me permission to pass on his response.

    Have to confess I’m not familiar with CG Dra, but that’s a very good light-curve for an almost 17th mag star (as expected for a 0.4m telescope in presumably a good site). It’s an eclipsing U Gem-type dwarf nova, here in quiescence, but I just looked at the AAVSO long-term light-curve and you can see that it outbursts quite frequently. That means it will be undergoing continuous mass transfer from the donor into the disc, and that displays itself as enhanced light when viewing either side of eclipse by the donor. In fact the hump here is quite broad, so it’s definitely an active system, and it’s clearly growing the disc in preparation for its next outburst.

    Given the obvious data noise that is also visible in the comparison star, my reaction is that there’s nothing that unusual here. Let me know if you think I’ve missed anything.

    • This reply was modified 6 days, 15 hours ago by Paul Leyland. Reason: Fix typpo
    in reply to: Star Count results #611088
    Paul Leyland
    Participant

    Additionally, use

    https://lighttrends.lightpollutionmap.info/

    Just checked the neighbourhood of my observatory.

    I very much believe that a large area to the SW of me is now Bortle 6-8 rather than 4-6.

    A very old saying: be careful what you ask for in case you get it.

    8-(

    in reply to: Mystery Observatory #611057
    Paul Leyland
    Participant

    Asking on behalf of a friend, does anyone recognise this observatory? It is thought to be in Australia.

    https://collections.museumsvictoria.com.au/items/774306 gives as much as I have been able to find.

    Definitely Australia, probably Victoria, possibly Bendigo. Circa 1900.

    • This reply was modified 2 weeks, 5 days ago by Paul Leyland.
    in reply to: New website feedback #610966
    Paul Leyland
    Participant

    Not sure whether this somewhat elderly thread is still current or whether I should start a new one.

    Over on SGL members were asked about their smallest telescope. Ever the pedant and firm believer that one should never ask for anything unless you are prepared to receive it, I pointed to an image taken with a 2.2mm f/1.8 refractor. This one to be precise: https://britastro.org/observations/observation.php?id=20191209_191900_36b00eba365581f4

    Now I am pretty sure when it was uploaded originally to the old gallery it was displayed upright and not sideways. Can it be fixed, please?

    No idea whether other images have been similarly rotated.

    in reply to: Back issues of BAA Handbook. #610714
    Paul Leyland
    Participant

    Already mailed my wants to David.

    I also have a few duplicates, so between us perhaps we can make a more complete collection for anyone else interested in building up a library.

    in reply to: Irish Astronomical Journal – free to a good home #610682
    Paul Leyland
    Participant

    Hmm, I can’t see how to direct message you from the forum interface. He is in Breaston, about 8 miles away from Nottingham.

    Please drop me a line at my firstname.surname (at) gmail dot com for his full address.

    Now arranged. Thanks James.

    Incidentally, how does one send a private message to another member? Anyone know?

    in reply to: Irish Astronomical Journal – free to a good home #610662
    Paul Leyland
    Participant

    Hmm, I can’t see how to direct message you from the forum interface. He is in Breaston, about 8 miles away from Nottingham.

    Please drop me a line at my firstname.surname (at) gmail dot com for his full address.

    in reply to: Redshift #610559
    Paul Leyland
    Participant

    There is no need to postulate expansion of space in order to explain redshifts greater than one, in fact you get z=1 for a velocity of just under 180,000 km/s which is quite modest and probably will be achieved by human artefacts[sic] sometime in the next few thousand years.

    I am not sure whether you consider tightly collimated clumps of electrons, positrons and protons as “human artifacts”. I do, because they do not occur naturally as far as I know, especially those of the positron variety.

    If you do include such things, we achieved such velocities many decades ago.

    in reply to: Irish Astronomical Journal – free to a good home #610557
    Paul Leyland
    Participant

    Tempted …

    My bother lives near by so collection would not be an issue for me.

    • This reply was modified 1 month, 1 week ago by Paul Leyland.
    in reply to: Elger; The Moon #610324
    Paul Leyland
    Participant

    If it had the maps, I suspect £1000.

    But it doesn’t, so my question remains.

    in reply to: New website feedback #610169
    Paul Leyland
    Participant

    And while I am on the subject: a preview-before-posting button would be nice too. Four edits in my earlier post could have been avoided …

    in reply to: New website feedback #610161
    Paul Leyland
    Participant

    We are told that BBCodes can be used to format our postings. I am one of those (very few?) weird people who have memorized a few such codes, such as [_i] [_/i] (underlines added for clarity) for italicizing intermediate text. I doubt that there are many other oddities like me. So, two questions:

    1) Would it be possible to provide a pointer to TFM for BBCodes for easy reference when posting and/or replying?
    2) Is it possible to provide buttons for pointy-clicky encoding of regions of text such as many other fora provide? See http://www.mersenneforum.org for an example where I post rather often if you want to see what I mean.

    • This reply was modified 1 month, 3 weeks ago by Paul Leyland. Reason: Edit tags
    • This reply was modified 1 month, 3 weeks ago by Paul Leyland.
    • This reply was modified 1 month, 3 weeks ago by Paul Leyland.
    • This reply was modified 1 month, 3 weeks ago by Paul Leyland.
Viewing 20 posts - 1 through 20 (of 475 total)