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Putaendo Patrick

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Everything posted by Putaendo Patrick

  1. A very nice telescope! Congratulations. By the looks of it, it should clean up very nicely. There's a complete one on ebay http://www.ebay.co.uk/itm/Astro-Astronomical-Refractor-Telescope-F-1250-Front-Lens-Dia-76-2-Kit-Box-Used/332103874620?_trksid=p2047675.c100011.m1850&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D41433%26meid%3D2f992a82a74340bd986faa197e8f362f%26pid%3D100011%26rk%3D1%26rkt%3D1%26sd%3D262184986699 buy it now for nearly 200 quid - expensive, perhaps, but another similar did sell for 149 pounds a while back. Circle K may have been made by Kenko - these small marks were put on most Japanese telescopes I suspect to identify them for a state quality control institute. If it's Prinz, this was a brand of telescopes and photographic equipment imported and sold by Dixons, in it's day a mayor high street chain of electrical goods - although if so, I'm surprised it is not specifically branded as Prinz. In the USA similar telescopes were imported by Tasco, K-Mart, Bushnell etc. John Diebel, the founder of Meade, in fact started by importing these type of telescopes from Japan which he sold by mail-order. I suspect your telescope was made in the late 1960s, perhaps early 1970s. There's some variation in quality, but the good ones are optically superb and, relative to todays prices, were quite expensive!
  2. Just learnt something new today! People used to clip the edges of silver coins thus devaluing their real worth which depended on their weight of silver. Newton became Warden of the Royal mint in 1696, and introduced milled edges for coins - these fine lines on the edge of the coin made it immediately visible that a coin had been clipped and was thus not legally valid. So I guess a coin to celebrate Newton is more appropriate than a banknote. http://blog.perthmint.com.au/2015/09/29/how-isaac-newton-helped-shape-our-coins/
  3. Most EPs will work with a focal ratio of f5 - but some will work better than others! You should get clear, sharp views in the centre of the field of view - but as you move out to the edge of the FOV things will begin to distort. More expensive EPs are corrected for this - but this is one of the reasons they're more expensive. Another consideration is the field of view itself. Plossls have quite a narrow FOV - about 50°. Other designs can give much wider views - but again the cost goes up. Another option to consider is a Barlow which increases the power of an EP by a factor, for example x2. It does this by increasing the apparent focal length of the scope - so an additional advantage is that it will reduce the focal ratio and be less demanding on the EPs. Cheap Barlows are usually a disaster, but from about 40 pounds upwards there are some good models. Personally I might look at 18mm and 12mm eyepieces with a Barlow which would effectively add 9mm and 6mm to your range and provide magnifications of x41, x62, x83 and x125 which would cover a lot of situations.
  4. Cloud in Durham! You asked for it Congratulations on a very nice looking telescope.
  5. New from Bresser, this would cost you 241 euros. It's a nice telescope, parabolic mirrors etc - so if it's in good condition, for 80 pounds you won't go wrong. I believe the more recent model has an improved focusing system, but there's nothing wrong with the older simpler system either.
  6. Hope this doesn't mean that the importance of his scientific research has been devalued by 50% Even Jane Austin's worth a tenner these days!
  7. The eyecups fit over an M43 thread and can be easily removed. Replacements are available, for example http://www.teleskop-express.de/shop/product_info.php/language/en/info/p7765_Baader-2454651---M43-thread-protection-ring-and-eye-cup.html in Germany - but I've no idea of distribution in the US. Presumably any other style of eyecup of the same diameter would fit easily.
  8. I believe your telescope has a focal length of 650mm - this is important to calculate the magnification a particular eyepiece will give. The Astromaster usually comes with 20mm and 10mm eyepieces which will give x32.5 and x65 magnifications. You should be able to see the moons of Jupiter and a suggestion of Saturn's ring at x65. However, to see more detail magnifications between x100 and x200 would be useful - a lot depends on atmospheric conditions on the night, sometimes increasing the magnification only increases a blur and you don't get better views. A 6.5mm eyepiece will give you x100 which is very possible with your telescope. 3.25mm would in theory give you x200, but I reckon this is pushing it for the Astromaster 130. A 5mm eyepiece would give a very useful x130. An alternative is to use a Barlow which effectively increases the magnification of an eyepiece. A x2 Barlow for example will double the magnification. Remember, however, the supplied eyepieces you probably already have are not the best quality. Combining these with a cheap Barlow will not work well. If you want to give us an idea of your budget, I'm sure you'll receive many suggestions for suitable brands.
  9. I said it before, but as your photo shows an old sun filter, I'll say it again - DO NOT USE IT. I suspect these filters were never that good to start, but age has perhaps caused them to deteriorate. With the intensely focused sunlight, these get very, very hot and have a tendency to crack or shatter. If you're observing when this happens and you get a flash of intense magnified sunlight through the scope, you could so easily be blinded instantly and permanently.
  10. I'm a little confused here (nothing new I assure you). There seem to be two 150mm aperture Bresser Messier telescopes. One has a long tube with a focal length of 1200mm and comes with a manual mount. The other has a focal length of 750mm and comes with a computerised go-to mount http://www.bresser.de/en/Astronomy/Telescopes/Bresser-Messier-NT-150-750-Hexafoc-EXOS-2-GoTo-Telescope.html# In theory this second one might be a very good option for combining visual observation with photography. For photography one of the key elements is a solid and precise mount. I don't personally have experience with the EXOS2 goto mount, but I feel it would work better on the smaller 150mm telescope rather than the larger 203mm telescope which is about double the weight (5.5kg versus 11.2kg according to Bresser specifications) - others who have this mount may disagree and I happily bow to their knowledge and experience. Another disadvantage of larger telescope tubes such as the 203mm is that they are easily affected by quite slight wind, causing the telescope to vibrate. This isn't too big a problem for visual, but isn't at all good for photography. For visual observing, bigger aperture is generally better - more light enters the scope allowing you to see fainter objects and obtain better resolution at higher magnifications. This said, to be honest the difference between 150mm and 200mm aperture won't give a staggering difference in views, and both can easily reach magnifications of x200 which is often the maximum you can realistically expect in the UK due to atmospheric conditions. And in any case, a lot of observing is done at much lesser magnifications anyway. The current range of Bresser scopes are relative newcomers on the astronomy scene. Bresser was taken over by Meade and became basically a Meade brand. However, a few years ago, Meade sold Bresser back to its original owners so once again it is "independent". On paper the Bressers have very attractive specifications, and I have been very impressed with a couple of Bresser refractor telescopes I have had the chance to use - so hopefully someone can comment on the Bresser mount.
  11. The modern, slightly different, version of this is the Danubia Delta 20. See: http://www.harrisoncameras.co.uk/pd/Danubia-Delta-20-Catadioptric-Reflector-Astro-Telescope_566032.htm The pdf English instruction manual for the current range is available here . Cornelius is correct, however, the original version was the Danubia RET50. The Japanese telescope industry used to be a bit like the old Swiss watch industry, with a lot of small companies fulfilling specialised functions. Some made parts, others assembled telescopes, and others did the marketing and export. A government body, the Japanese Telescopes Inspection Institute (JTII) oversaw quality control and often marked approved telescopes with a small sticker. For the JTII to know who actually made the optics, I suspect there was a requirement to identify the maker of the lenses or mirrors. This was usually a very small symbol - in the case of Towa, a letter T inside a circle. Sometimes, however, identical models of a telescope (for example Tasco in the US) have different symbols - suggesting that the optical components came from different sources. Towa were quite a large company and may have produced Danubia telescopes from start to finish, but they also provided parts to other companies. Terribly confusing, at least to me .
  12. Take care - ants magnified x200 can give you quite a nasty turn!
  13. Your telescope is basically a copy/clone/alternative version of the Celestron Astromaster 114 (still in production) and probably dates from the mid 1980s. Whilst certainly not a research grade scientific instrument, when it was new it would have been considered a good beginner's telescope. Over the last thirty years, however, there have been significant improvements and better telescopes are now comparatively cheaper. If you can get a half decent working telescope for 55 pounds, I don't think you've done badly at all . I'm guessing your scope was made in Japan and predates the mass migration of cheap telescope production to China. These type of telescopes were exported and branded locally in Europe or the USA, sometimes by astronomical suppliers such as Meade or Celestron and sometimes by department store chains (in England, for example, the Dixons High Street chain of electrical/photographic shops marketed similar telescopes under the Prinz brand). I believe a German company called Dörr were/are behind the Danubia brand, but I'm afraid I know nothing about Dörr. Some older Danubia telescopes have optics made by Towa, a Japanese company which was capable of producing very good optics. Don't expect this telescope to perform fantastically - but if all the parts are complete and the mirrors are in reasonable condition, it may be surprisingly adequate for a basic beginner! Don't write it off quite yet. If it works, you can get a lot of observation under your belt, and if the hobby grabs you, you can buy a bigger, better scope in the future. You may want to measure the diameter of the focuser tube and eyepieces: they may be 0.9 inches, an older size which will make getting better eyepieces quite difficult. On the other hand, if the diameter is 1.25 inches - any standard modern eyepiece will fit, and you may be able to improve viewing with inexpensive second-hand Plossls (15-20 pounds). Equally, you may be lucky enough to have a couple of decent original Kellner eyepieces, some of which can be really quite good. Beware - some of these older telescopes came with very inadequate and unsafe solar filters. Please DO NOT USE THESE TO VIEW THE SUN. And, although looks aren't everything as they say, in my opinion it's a pretty cool looking telescope .
  14. Bintel for Kendrick in Australia: https://binocularandtelescope.com.au/product-category/other/dew-control/
  15. You might look at Astrozap, heated bands, heated dew shields and controllers: https://www.astrozap.com/scripts/default.asp Some of their products are available in New Zealand from N.Z. Telescopes http://langwoodsphotography.com/eshop/Astrozap_Dew_Controller.html I think https://www.altairastro.com carry Kendrick products in the UK who may be able to send you what you need. Maybe also Teleskop Service in Germany: http://www.teleskop-express.de/shop/product_info.php/language/en/info/p7327_Kendrick-Heater-for-glued-Newtonian-Secondary-Mirror-with-stalk-thinner-than-50-mm.html Likewise, perhaps there are dealers in Australia - so maybe a question on the Ice-in-Space forum? There are also a few small manufacturers, for example R-Sky Instruments in the UK : http://r-sky.org/en/products And, if you have some electrical knowledge and skill, you may be able to make your own. For example: http://www.deepskywatch.com/Articles/newtonian-dew-heater.html
  16. Welcome to the forums, and good luck with your project! Light pollution is one of the biggest problems for astronomers. Ideally there is zero artificial light in the vicinity, hence top level research observatories are often in very remote places such as the Atacama Desert in Chile. However, this also means access is difficult for the general public. This picture gives an idea of the difference: Amateur astronomers often use the relatively informal Bortl Scale to estimate light pollution: https://en.wikipedia.org/wiki/Bortle_scale You need to minimise two types of light pollution - local illumination, such as street lighting, which can often be screened to an extent to reduce adverse effects, and the cumulative effects of large quantities of light, for example in an urban situation, and the best solution is really to move to a rural location. It is worth remembering, too, that certain frequencies of light at low levels do not damage night vision. Red light for example is often used by astronomers, and there is some research suggesting other colours such as green may be advantageous. Something perhaps to think about when planning safe access for the public. Night vision is also a gradual process - taking perhaps 30 minutes for our eyes to adapt after being exposed to any bright light. Hence it is important to avoid occasional exposure to bright light, for example a car arriving in a parking area during observation. As I see it, the problem of determining exact light radiance levels is the variable of moonlight. Bright nights when the Moon is full are not ideal for many types of astronomical observation, but they are something we cannot control!
  17. Earlier this year I bought I second-hand 100mm spotting scope to use as a very quick grab-and-go for astronomy - and, although not perfect, for 50 pounds approx, it has been great fun and gets a lot of use. However the Regal M2 is considerably more expensive, and personally I feel for astronomy you would be better with a similarly priced short-tube refractor. Advantages include better focusing, eyepiece interchangeability (including 2" EPs), filters, option of right angle diagonal, better finderscope possibilities etc. Perhaps something like this: https://www.altairastro.com/Starwave-80ED-R-V2-FPL53-Refractor-Telescope.html with a focal length of 550mm, but shorter, more compact fracs are also available if space/weight is an issue. There are adapters to allow you to mount a dovetail on a photographic tripod, for example: http://www.tringastro.co.uk/starwave-mini-vixen-format-clamp-to-fit-camera-tripod-9648-p.asp I reckon this would be just as fast as mounting a spotting scope.
  18. Thanks, Steve - it looks very close indeed! I'm sure you're spot on. And, Peter, before you smash open the piggy-bank, the currency is Chilean pesos - which at the moment, with the horrid exchange rate, is a wacking 43,050 pounds! For reference, two similar Unitrons (with wooden tripods) sold a few years ago in the US and in Australia for about 3,700 pounds each according to today's exchange. So either Carlos Muñoz has a seriously wealthy cult following, or the seller has no idea
  19. Currently up for sale in Chile is this telescope: The fact that it is wrapped in plastic doesn't exactly help to identify it! It comes with a load of Cave Optical Co. brochures, so could it just be one of the few Cave refractors which were apparently produced? Or perhaps a Unitron? Any thoughts very welcome.... The telescope belonged to Carlos Muñoz Ferrada, 1909-2001, a Chilean astronomer who had certain success predicting earthquakes and claimed a giant comet/planet Hercolubus would destroy the Earth in 1999 - a perennial theme in Latin American pseudo-science! It's rumoured the police wouldn't let him out of his house as he tended to panic the population. The asking price, if you need to ask it's not for you , a little over 35,000 pounds. I certainly won't be buying it any time soon, and doubt anyone else will either - but it very definitely piqued my curiosity. http://www.yapo.cl/region_metropolitana/hobbies_outdoor/telescopio_de_carlos_munoz_ferrada_35380990.htm?ca=15_s&oa=35380990&xsp=45
  20. I have to admit I rather admire the good doctor and the English passion for defending lost causes! Although I certainly agree that protecting our own planet is of primary and perhaps more urgent importance. In the late 1950s, the US government (or military) contemplated the possibility of using the Moon as a test ground for atomic bombs! One of the scientists who worked on Project A119 as it was called was none other than Carl Sagan, who otherwise seems like quite a decent chap! Hopefully any thoughts in such directions are for the moment shelved, but sadly, who knows in the future? In the end, what ever the outcome of Philip Davies's attempts, should a time come in the future when we are able to, and need to exploit the Solar System, it will be those countries that have the power and force to do so who will benefit. The USA for one doesn't seem to have much respect for international law especially when it is in conflict with its own interests.
  21. Great post - thanks for taking the time to assemble and write up the list. Another useful source (with a fair amount of overlap) is the SAO/NASA Astrophysics Data System which provides abstracts of some 300 works by Feynman or about him and/or his research. Quite a lot of the articles, dating back to 1939, are available as downloads. http://adsabs.harvard.edu/cgi-bin/nph-basic_connect?qsearch=Richard+Feynman&version=1
  22. This diagram make help you to understand what is happening inside your reflector telescope, as compared to a refractor which uses glass lenses:
  23. First, your telescope probably came with an Equatorial mount on a tripod. This is specially designed to allow the telescope to follow the stars, planets etc. as they "move" across the sky (they don't, but appear to as our Earth rotates). Check this Youtube video: Next you want to check the small finderscope is aligned with the main telescope. In daylight, centre the main telescope on a distant object such as a church tower, radio mast etc. and tighten it so it doesn't move. Then adjust the screws which retain the finderscope so it too is centred on the same point. Then you're done and in future (except for occasional fine tuning) when you use the low power finder to locate objects in the sky, the higher power main telescope will be centred. Be aware that one of the disadvantages of your telescope is that the eyepieces are 0.965 inch diameter. This means you cannot use the more common 1.25 inch eyepieces which are now almost universal. It may be possible to buy a new 1.25 focuser or an adapter, although ultimately cost may not be justified. Otherwise keep a lookout for secondhand vintage eyepieces, but remember most will not be top quality (unless you're lucky enough to stumble on Zeiss, Nikon or Pentax etc - but this is very remote). Finally, once you've got your telescope up and working, you may want to check it for colimation. Reflector telescope like yours use two mirrors and for best results these need to be perfectly aligned. If you are near an astronomy club, one of the members may be prepared to talk you through it first time. At first it seems complicated, but you soon get used to it.
  24. The problem is that you are using low magnification eyepieces. The 25mm is giving x26 and the 20mm is giving x32.5 in your scope which has a focal length of 650mm. Ideally you need something like a 5mm which will give x130 to be able to observe the planets with some detail.
  25. More of an EP and accessories bag rather than a case. The Missus found this secondhand in a flea-market near where she works and bought it for me - I think it's great!
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