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Topic: Neptune and Triton
After some success imaging Uranus and its satellites back in January I had a go at Neptune and Triton at the end of May. I used a remote telescope at Siding Spring, Australia which is part of the iTelescope network.
Given that Neptune is blue due to strong methane absorption in the red part of the spectrum I used a red filter to reduce glare from the planet and help to pick out Triton. The seperation of the two was only 11.5 arc seconds at the time the image was taken with Triton at magnitude 13.5 and Neptune at 7.8.
I’m hoping to get a sequence of images over several days to show the motion of Triton through its 5.8 day orbit of the planet.
Mike.
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In reply to: Dudley Fuller (1929-2014)
Sad news indeed and the end of an era. I always enjoyed the entertainment of meeting Dudley Fuller when I visited Telescope House in London. For several years as a teenager I owned a Fullerscopes 6-inch reflector with “A” grade optics in a shiny white tube on a MkIII mounting. And one of the best views of M13 I have had was with the 18-inch Fullerscopes Newtonian at Charterhouse (Nick, I didn’t break it – it was somebody else who grabbed hold of a massive tube counterweight which came off in his hand – I just had to stand there balancing the tube on my head whilst help was summoned!).
Jeremy
In reply to: PST Help please
I finally found a thumb screw to fit my PST eyepiece holder. A friend had an cheap old Japanese refractor that he bought through a newspaper advert many years ago. The telescope is rubbish but the thumb screw fits!!! Perhaps there is a moral here….never throw away any astro bits. 🙂
Thanks to all those who submitted suggestions
Terry
Topic: PST Help please
I have a PST which I’ve owned for about 7 years. Unfortunately, I’ve lost the small thumb screw that holds the eyepiece firmly in place while observing. The telescope is made by Meade and I contacted their main dealer (Telescope House) for Coronado PST’s. They informed me that they have been trying for months to get this spare (and others) from Meade but to no avail. I’ve even phoned Mead direct in the USA and they were totally unhelpful and unsympathetic. They just referred me back to their UK dealer! Does any Member know where I can obtain a suitable eyepiece thumb screw. I know it’s only a small item but it’s an important one.
Perhaps Members might also like to be aware of Meade’s apparent customer care attitude to an owner of their product in the UK!
In reply to: sad news of death of John Dobson
Posted by Terry Byatt at 18:57 on 2014 Feb 01
Very sad. John brought the opportunity of owning (or building) a large telescope to those of us with limited funds to spend on our hobby.
In reply to: Horace Dall – Rough stuff across Iceland
Posted by R A Marriott at 03:37 on 2014 Jan 26
I&I News, New Series No. 11 (9 May 2013) is a 33-page issue dedicated to Horace Dall. It includes Jim Hysoms obituary of Horace; Over unknown Iceland on a Raleigh roadster by Ben Searle, with a selection of Horaces photographs; Horaces papers on The camera obscura, A null test for paraboloids, FP3 Series II film, Atmospheric dispersion, Maksutov telescopes, Visual astronomy in the ultraviolet, Telescope eyepieces, Finding and guiding on dark skies, Photoelectric methods in amateur astronomy, Filter-type solar prominence telescope for amateurs, and A DollondWollaston telescope; Comments on the null test by F. J. Hargreaves; Memories of Horace Dall by Robin Scagell; The genius of Horace Dall by Martin Mobberley; Horace Dalls observatory by Mark Stuckey; and two short pieces by myself, on the protoype Dall-Kirkham and the Horace Dall Medal and Gift. It also includes links to Robin Scagells 52-minute video of Horace, filmed in 1982, and Gee Hurkmans 6-minute video of his cycle journey across Iceland in 2010. Like all issues of I&I News, this issue was sent to all Members with e-mail, and is available for download (when logged in) from the Members Only area of this website: Menus – Members/Downloads/Sections/Instruments and Imaging Section/navigation link 2. It is also available for download from the Instruments and Imaging Section website at http://www.britastro.org/iandi/iandinewsdall.htmBob Marriott: Director, Instruments and Imaging Section
Posted by Denis Buczynski at 14:38 on 2014 Jan 16
I pass on sad news of the death of John Dobson the American astronomy populariser and inventer of the Dobsonian telescope design. A tribute can be found at the link:http://earthsky.org/space/r-i-p-john-dobson
Posted by Peter Howard at 11:31 on 2014 Jan 15
I am giving away Journals 1998 to 2007 because of space restrictions. Also Sky and Telescope magazine 2000 to 2008, BAA Handbook 2001 to 2010, and VSS Circulars No 97 (Sept 1998) to 153 (Sept 2012).
In reply to: My 14 inch AE in Horace Dall’s dome
Posted by Americo Watkins at 19:32 on 2014 Jan 10
Martin,I think it would be interesting to see some lunar/planetary images taken with modern equipment using the restored telescope.Eric
In reply to: My 14 inch AE in Horace Dall’s dome
Posted by Martin Mobberley at 15:41 on 2014 Jan 10
I’ve been meaning to upload some recent pics sent to me via Mark Stuckey. Last year Mark resurrected my old 14 inch AE ‘scope, which I gave him some years ago, and he installed it in Horace Dall’s old dome, hence this thread. However, Mark has now completely and magnificently restored Horace’s 15.5-inch Dall Kirkham too, first built in 1938, and kept from 1986 to 2013 by Luton A.S. So Horace’s famous old telescope and its dome are now re-united and both are in absolutely pristine and fully working condition, thanks to Mark. From the late 1930s to the early 1980s this telescope took most of the best lunar & planetary photographs taken from the UK.The latest pictures are here:http://martinmobberley.co.uk/images/IMG_3479.jpghttp://martinmobberley.co.uk/images/IMG_3480.jpghttp://martinmobberley.co.uk/images/IMG_3482.jpghttp://martinmobberley.co.uk/images/IMG_3483.jpghttp://martinmobberley.co.uk/images/IMG_3484.jpgQuite a staggering double restoration job by Mark I think!!Martin
In reply to: Anybody still using an SX-MX916 CCD
Posted by Mike Harlow at 19:10 on 2014 Jan 09
Hi Paul,I’m no software expert I simply use the MX916 for acquiring images using the Starlight Xpress interface and process using IRIS. Very basic stuff. All I can say is that the MX916 is a very good camera in terms of sensitivity with it’s 11um pixels and low noise.So if you want to do some science it’s an excellent camera. If you want to take ‘pretty pictures’…maybe not so good because of it’s relatively small size. I recommend science!!!You may be interested in the image below which shows the spectral response of the camera. I got into spectroscopy last year and compared different telescope and detector combinations. The MX916 goes from about 360nm to beyond 950nm which again is a very useful spectral range.I can certainly recommend it…Mike.
In reply to: Anybody still using an SX-MX916 CCD
Posted by Nick Atkinson at 17:24 on 2014 Jan 07
Hi Paul,I suggest that you first contact StarlightXpress telecom 0118 402 6898 as they should be able to advise you on their software downloads for this camera and is free of charge.If you do not have a GOTO mount AIPWin.V2 is a good option and coming with a free book is VAT exempt. and will provide all the image manipulation features plus calibration. Should you wish to submit variable star photometry to the BAA it is fully integrated with this package.You do not say which mount you have, if this a GOTO then Astro Art and Maxim DL can be considered. AstroArt is the cheaper option but I cannot advise on this.You can download MaximDL plus Maxpoint for a free 30 day trial and all features can be tried. At $599 for the download option it is expensive but is fully featured for telescope and camera control and uses a StatlightXpress universal drivers for both your camera and auto guider. First check with SXP to see if the universal driver will support your camera. Maxim has been featured for over the last year in Astronomy Now. I use this package and have not been disappointed. The £ to $ exchange rate is favourable now.Maxpoint will integrate with Cartes du Ceil free planetarium software but you will need to down load an ASCOM driver. Later on you could always add on another planetarium.Clear skies,Nick
In reply to: Martin’s new Patrick Moore Biog
Posted by Martin Mobberley at 15:39 on 2014 Jan 05
I will only be contributing one post to this thread, simply because the forum is not a place for advertising my book, and there is no such thing as bad publicity, as any author will tell you! All discussion on a publicly visible forum simply increases the book’s Google presence and therefore its sales!First, I’d like to thank those people who have sent me e-mails saying how much they have enjoyed reading the book since its publication in August. These e-mails now exceed 100 in number and originate mostly from BAA members of long standing, mainly those born in the 1950s, and those who knew Patrick well. The general response has been very similar in tone to the JBAA review by Dr Mitton and the Cloudy Nights thread on the subject.Writing a book about such a popular figure was never going to be easy, but I had plenty of advice. Most of it, from experienced authors, warned me that I would be very tempted to write a hagiography (simply hero worship) and leave out the negative stuff. But this was never my plan. Having spent more than ten years unearthing everything about Patrick there was no way I would be shoving the bad stuff under the carpet. It would be a waste of a decade of work and others would soon reveal the information anyway. I knew that others were planning biographies of Patrick too, so mine had to be released promptly. No-one would spend a decade on a project just to sit back and see less comprehensive ones be published first! Even in Patrick’s lifetime a few (such as Richard Baum and Ewen Whitaker) had dared disclose flaws in Patrick’s stories, such as the murky Mare Orientale business…..After their paper was published in the JBAA Patrick issued an apology of sorts on TV and in a JBAA letter….To omit everything negative of this type would make the biography of little historical value.Patrick will always be a hero figure to me and a man who shaped my life, but to deny he had serious flaws would make my book no more than a fan-worship book, with no real substance. It is clear from Dr Simon Mitton’s review of ‘RAF Blazer’ that he feared it might be just that…..a hagiography, but clearly he was very pleased to see that it was, instead, a comprehensive account and I had not chickened out from writing the truth, whoever it annoyed. As we all know, Patrick always spoke his mind, and I have done the same with the ‘RAF Blazer’ book.One term that keeps occurring in e-mails I have received is that this must have been a horrendous task to get the mixture right, but that ‘you have got that tricky balance dead right’. It was not easy, and the 330,000 wordswere read and re-read several dozen times before I was happy. Even so, a few other authors did tell me: "If you say anything negative about Patrick, anything at all, there will be a witch hunt and you will be lynched by the baying mob, who will have no interest in the facts….." One astronomy author told me he would never write anything negative about Patrick as "I would surely be beheaded with a meat cleaver…" Fair enough, but the baying mob has not appeared, just a daily influx of ‘thankyou’ e-mails. If a few people would prefer a book that was 100% positive about Patrick, and omitted almost everything prior to the late 1950s, then Patrick’s own book, in ’80 not out’ and ‘The autobiography’ format, is still available. The reader has a choice! Indeed, there isanother option too….the critics can write their own biography of Patrick if they prefer. I have already had half a dozen e-mails (and some letters) insisting I must write a follow-up book! Perhaps I can quote from a personal letter received from Dr Allan Chapman last week, who was a good friend of Patrick’s over many years:’Dear Martin, I really must let you know how very much I am enjoying your RAF Blazer biography of our dear late friend Sir Patrick. I think that you have struck exactly the right balance: how to write a sharp and penetratingbiography while still displaying a deep affection for the man and his fables: I did so laugh at "Tut, Tut, Naughty Patrick" regarding the RAF.’ Allan goes on to note that some of Patrick’s negative points weresimilar to those of Galileo, so he was ‘in good company’.If such a close personal friend of Patrick’s, and such a noted historian, thinks I have got the balance exactly right then I am more than happy…..Patrick’s closest friends all agree that he had some major faults, but he was such an entertainer and raconteur that it was almost impossible to dislike him, whatever he said or did!!As I say, this will be my final forum posting on this subject, but I am happy to answer (even more!) e-mails via martin.mobberley@btinternet.com, even if I am currently spending about six hours a day answering queriesabout telescope problems and Patrick…..Martin
In reply to: Observing stats: how was 2013 for you?
Posted by M C Butcher at 13:47 on 2014 Jan 04
I had thought that 2012 was not a good year but then 2013 came along and it was much worse!During the year I observed on 9 nights only (for a total of 16 hours 35 minutes). On all other occasions it was either cloudy or too windy or both. My best months were August (2 nights 4 hours 50 minutes) and October (3 nights 8 hours 25 minutes).A very windy year, 2013 saw 2 days with Violent Storm Force 11 winds, 5 days with Storm Force 10 winds, 13 days with Severe Gale Force 9 winds and 43 days with Gale Force winds. Since mid-October it has been too windy to set up a telescope.I missed 14 nights through being absent.Here’s hoping for a better 2014.Martin ButcherIsle of Colonsay
Posted by Jeremy at 10:51 on 2014 Jan 01
How was 2013 as an observing year for you? Better or worse than previous years? I found it a reasonable year. So, to get the ball rolling, here are my stats for 2013This year I was able to observe from home in Cheshire on a total of 125 nights, or 34% of all nights, an improvement over 2012s total of 108. (Note that a usable night is when I was able to carry out any CCD imaging: it could be a few fields/frames or it could be many hours). The best month was November with 15 nights, with April and July each yielding 14. March was disappointing with only 3 nights its normally one of the better months for me.I should add that inevitably there were some clear nights that I missed due to holidays, business travel or other commitments, so the totals are underestimates. In fact I was able to observe in my hols in Turkey for each of the 14 nights, when I was also able to estimate the magnitude of Nova Del with my binoculars. Oh, to live in sunnier climes!The total number of individual fields imaged this year was 9296 (one measure per star, as part of a patrol for outbursting cataclysmic variables); this number does not include time series photometry, when I sat on a particular star for hours. Of this number, 1070 observations were made remotely using the Bradford Robotic Telescope on Tenerife.Since my stats began in 2005, the best year was 2006 with usable 41% of nights usable.Clear skies for 2014!
In reply to: DSLR and the Horsehead
Posted by Graham Relf at 11:51 on 2013 Dec 20
Yes, I do have a flat box (cardboard box lined with white paper, 4 torch bulbs in the corners next to the circular aperture that goes over my telescope). I still do not often use it. I agree that it’s a simple way to fix vignetting but I tend to do that in post-processing (various methods).I would certainly use my flat box if I had any optics between my telescope and the camera body (to magnify the target*) because there is then a risk of out-of-focus dust spots and rings which a flat frame would correct.(* or perhaps a coma corrector but again I have one but don’t use it because I found it introduces other problems such as ghosting from bright stars – the coma is not conspicuous in my Horsehead photo). I think the golden rule (as in software development) is to keep things as simple as possible.
Topic: DSLR and the Horsehead
Posted by Graham Relf at 12:05 on 2013 Dec 17
I just want to correct an unfortunate impression given by one of my photos in the current BAA Journal (2013 Dec, p364). The photo has printed very dark so it implies that the Horsehead Nebula cannot really be photographed with an unmodified DSLR. Nothing could be further from the truth. A better version of my photo can be seen here.It was taken with an unmodified Canon 5D MkII at the prime focus of a 10" (250mm) f/4.8 Newtonian on an unguided HEQ5 mount, 81 exposures of 32s each, stacked and post-processed by my own software. An earlier attempt can also be found in the BAA Gallery.I am constantly trying to explain to beginners that, contrary to what they may read in Internet forums, they do not need a lot of expensive equipment to be able to photograph amazing things in the night sky. All you really need is a digital camera, something to fix it on, and some free stacking software. Oh, and get out of town for some darker skies. A motorised tripod is desirable but not essential if you take short enough exposures (see our field of view and trail calculator ) but more of them. Many interesting objects are too large to fit into a telescope’s field of view, so a telescope is optional. And if you balance ISO, exposure time, and number of exposures a guiding system is certainly not necessary (I haven’t yet felt any need to get one).I have a book in preparation which expands on that message, to try to encourage beginners to get out there and have a go. It will be available in the New Year. More details later.
In reply to: Limiting Magnitude
Posted by Martin Mobberley at 16:02 on 2013 Dec 08
You’ve got most of it right Eliot, yes.Seeing is basically down to turbulence….which determines how bloated the stars will appear in long exposures…. Of course, if your drive is poor and the stars are drifting around by arcseconds during the exposure, this will have a similar effect in limiting the magnitude. Bad light pollution will mean the signal-to-noise ratio gets worse….so 20th mag objects are sitting on a wall of light pollution… For example, you may find that objects on the limit of detection are only 1% brighter than the background sky, so given that the background sky is noisy and noise is random, the signal gets swamped by the noise. Without filters the stars can spread out, yes, but this rarely becomes a factor with reflectors, although for planetary imaging filtering is usually essential due to the spreading of light due to dispersion and the desire for sub-arcsecond resolution. Some telephoto lenses produce bloated stars and do need filtering to cut out violet haloes. Filters are desirable for photometric work on bright objects, but dim the light so much below mag 15 or so that they make the image very noisy…..OK if you have a huge telescope and like long exposures, but they do hammer the limiting magnitude.Clearly you are already getting to grips with letting Astrometrica allow for the object’s predicted motion…….Martin
Topic: Limiting Magnitude
Posted by Eliot Hall at 15:53 on 2013 Dec 04
I have question about limiting magnitude of my kit. Looking at the Minor Planets Center website most of the asteroids listed above 19th magnitude in the V-Band.Last weekend decided to hunt for some faint asteroids. Cartes du Ciel said that there would be 3 20th magnitude asteroids in the field of view of a galaxy I was imaging. I double checked the ephemeris on the MPC website none of the asteroids required further observations; therefore I assumed that they had stable orbits.I imaged the target area with my f/4.7 10inch Newtonian with a Starlight Xpress MX916 through a UV/IR cut filter. I look 10x60s and 10x120s exposures with darks and flats. The telescope was pointing above 50 degrees elevation. Using Astrometrica and Cartes Du Ciel I scanned the regions of the image where the asteroids should be. However I could not find any trace of them. Using the object selection tool in Astrometrica I measured at the V magnitudes of the faintest stars in the image. The faintest I could make out were between 18th-19th magnitudes.1.Am I being unrealistic expecting to find 20th magnitude asteroids using the equipment Ive got?2.Have I hit the skys magnitude limit? I live on the edge of a village and the seeing was OK but not brilliant. I also tried analysing a few 300s subs from the same night as well but couldnt see any extra stars.3.Do I need to stack the images to get a better S/N ratio? If so how can the images be aligned on something you cant see?Eliot
Posted by Comet Section at 17:36 on 2013 Nov 07
Hello , Ernesto Guido has pointed out this paper.This paper has just been published on Arxiv:"The Extraordinary Multi-Tailed Main-Belt Comet P/2013 P5"http://arxiv.org/abs/1311.1483Take a look at the image in the paper :)https://twitter.com/comets77/status/398393156804153344/photo/1"Hubble Space Telescope observations of main-belt comet P/2013 P5reveal an extraordinary system of six dust tails".
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