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allworlds

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Everything posted by allworlds

  1. I gave up on one possible observing site due to feeling unsafe. It was supposed to be closed to cars at night, but it wasn't, and quite a few people were parking up. And perhaps it was just my paranoia but I thought I was being followed while driving away. Not returned since. I find going on my bicycle can be better. The scope and tripod are heavy and awkward to carry on foot away from a car parking space which led to me setting up too close. But I can wheel the bike right to where I'm observing from. In general I feel safest if somewhere is either dead remote and quiet so nobody is likely to go there looking to cause trouble, or reasonably busy so that nobody can cause trouble without risking getting seen. (But busy conflicts with dark adaptation). It's the "in-between" situations where it's me and maybe one or two other parked cars or groups, that's what makes me feel unsafe.
  2. Looked for and found comet 2022 E3 with the binoculars. Faint round averted vision fuzzy that I would never have noticed if I didn't have Stellarium showing me exactly where to look. Still, more than I've seen in a little while.
  3. From what I have read, the courts accepted the argument that camping is not "open-air recreation". Although just one landowner was involved in the court case I think all of Dartmoor's owners could now use this as precedent. No reasonable person could consider stargazing to not be open-air recreation, but nonetheless I would not be surprised if some landowners feel emboldened to harass or order stargazers away.
  4. The ecliptic is inclined relative to the equator. During northern hemisphere winter, the sun appears well south of the celestial equator and so doesn't rise very high. The full moon is directly opposite the sun so during winter it appears well north of the celestial equator and so rises high in the sky.
  5. A great choice I think and definitely a real bargain found. I would stick to 25 mm as your lowest magnification eyepiece. You might find the secondary shadow becomes noticeable with lower mag. If you use the solar filter, tape it securely to the scope. A few weeks ago I read somebody had the filter on a Bresser scope blow off in a gust of wind.
  6. A great choice I think and definitely a real bargain found. I would stick to 25 mm as your lowest magnification eyepiece. You might find the secondary shadow becomes noticeable with lower mag.
  7. For visual use focal length isn't very important because you can just use different eyepieces to get your range of magnifications. It matters more for refractors because a shorter focal length creates more chromatic aberration. The Maksy 60 is very cute. But yeah, unless you're handy with DIY/woodworking, a good mount even for a small and light scope isn't the cheapest thing. I wonder if you could make it fit on the Heritage 76's mount? It would take a bit of DIY but if it works and you can swap back and forth then they'd pair together nicely - the Heritage does widefield and the Maksy does lunar and planetary. With a hybrid diagonal for the Maksy they can use the same eyepieces. That's probably the cheapest way to get more out of the Maksy, if it works. A decent camera tripod with a ball head is another idea. The "trick" is don't perch the scope on top like the Maksy 60's box shows, but instead put the ball head sideways in the notch.
  8. I have a Skywatcher Heritage 76. The Orion Funscope, Meade Lightbridge Mini 82, and some but not all models of the Celestron Firstscope are similar. I find it easy to use and got a lot of enjoyment out of it, but it's a very cheap telescope and does have its limits. Great for the Moon, the Milky Way, and star clusters. Also good for hunting down faint fuzzies because it can give a wide angle view for easy star hopping, wide enough that you can get by without a finder. But very poor on planets, it'll show the major features - you'll see Saturn's rings - but little true detail because the cheap mirror limits the magnification to about 50x. (With the Firstscope models, watch out for the eyepieces. Most come with H and SR eyepieces which are bad. Some such as the "Cometron" variant come with much better Kellner eyepieces.) The two more expensive Dobsonians you linked in your most recent post are much better. Parabolic mirrors mean they can give sharp high-magnification views, and the aperture is bigger, and they still have much of the same ease of use. I advise against the Starsense Explorer 114 that you linked. It uses a "Bird-Jones" optical design that isn't very good. In a telescope costing 250 Euros you can do better.
  9. You don't actually need a lot of power. 5 milliwatts is plenty. If you're pointing out a target, circle it rather than pointing the laser directly at it. That way if it is actually an aircraft you won't lase the pilot. Sometimes an aeroplane looks like a planet or the ISS. I wouldn't use one at all if I was close to an airport.
  10. For me the old travel cliche applies: It's not the destination, it's the journey. Sure I'll look at the Moon and planets, but hunting fuzzies is my real calling. In a small scope they're not much to look at; the activity is in the process of locating and seeing them. (Edit: Well, most of them aren't much. The Pleiades and similar always look great.) That said, photons that have travelled across the vastness of space, a handful of the gazillions that were once emitted, and landing upon my own eye. There's something special about that.
  11. Hope you get on well with it. I would have advised to skip the Barlow and the moon filter anyway. Moon filters are a matter of taste and you might be quite happy without one, and I've not found cheap Barlows all that useful.
  12. I read this from beginners quite often. Personally I think viewing planets is more demanding on the telescope than viewing DSOs, since planetary viewing is done at high magnifications where flaws in the optics or mount are most apparent. DSOs are harder to find and affected by light pollution but more forgiving of flaws in the equipment. But £300 is plenty of money to get a telescope that's good all round. Anyway, the Heritage 150P and the Explorer 130P AZ5 are both good choices. Optically they're good all-rounders and the difference between 5 and 6 inch aperture isn't much. I say "It's the mount that counts" and I think they're both simple and stable. With the tabletop Dobsonian you probably want to put it on something though some people do use them on the ground. That's not much trouble at home, a wooden stool or small table does the job nicely, but it can be an issue if you're going somewhere to observing; lightweight camp tables or plastic garden furniture won't cut it. The tripod mount avoids that concern but you can see the price of a good mount like the AZ5 Deluxe. Either will easily fit in a car boot and won't be too hard to carry. Regarding the two 4 inch Maksutov-Cassegrains. I have an ETX 105 myself (same as Phillip R). It's compact enough to fit in a backpack or a bike basket and it gives very nice planetary views but it is a drop in aperture. I also find the long focal ratio makes star hopping to deep sky objects that bit harder because it limits the maximum true field of view. I can still view DSOs with practice, patience, and good star charts or a phone app, but I think a shorter focal ratio is more beginner friendly. My bigger reservation is the mounts and tripods - they are not as good as the AZ5 Deluxe. That said maybe some owners of those mounts can chime in. I don't like Newtonian reflectors on equatorial mounts, so I'd give the StarQuest 130P a miss. Don't let Bortle class stop you observing DSOs. True, they will look better from dark skies, but most DSOs are still observable in the city. What matters more is getting away from nearby lights and getting dark adapted. If you have streetlamps or insecurity lights shining into your garden that's a problem. I'm forced to find a park to have any hope of serious deep-sky observing, which then gives me concerns about personal safety.
  13. Wed night it was I think I managed to spot Mercury at about 4 pm, just after sunset. Scanning the area with binoculars I spotted a point of light which I could then also make out naked-eye. Now either that was Mercury and Venus was behind the bank of cloud below it, or that was Venus and Mercury was invisible, but I don't think it was bright enough to be Venus. Jupiter was also visible and brighter than probably-Mercury. Solid cloud Thurs and tonight so I haven't been able to make another try.
  14. Resolution is the term you are looking for. Because light is a wave, a telescope (or even our unaided eye) will focus a perfect point source to a small disc of light called the Airy disc. Therefore two point sources that are too close together can't be distinguished from a single source. The angular resolution of a telescope with perfect optics, in radians, is approximately equal to the wavelength of light divided by the diameter of the telescope's main mirror or lens. As a practical formula, Dawes' limit is: R = 116/D Where R is the resolution in arc seconds and D is the aperture in mm. (Sidenote. Put in 3 mm, for the typical size of our eyes' pupils in daylight, and you get R = 39 arc seconds. The actual resolution of healthy human vision is about 60 arc seconds. So our eyes are not far off the limits imposed by the laws of physics and their own size.) You then need sufficient magnification for your own eye to see the detail the telescope resolves. and furthermore you'd like the detail to be clear, not just barely visible. So the rule of thumb is that maximum useful magnification is 2x per mm of aperture. Too much magnification and the image becomes dim and obviously blurry. And you also need sufficient optical quality and precision. In reality no telescope has perfect optics. But a decent parabolic Newtonian reflector, Schmidt-Cassegrain, or apochromatic refractor will all come close in the centre of the view. The Newtonian reflector is the cheapest for a given aperture - remember, more aperture means better resolution. Here are simulated eyepiece views of Saturn at 200x in a 60 mm scope ("too much magnification") and at 200x in a 200 mm scope. You can see how the larger aperture scope gives a brighter and crisper image. (The simulation isn't perfect but it gets the idea right). https://imgur.com/a/uUGmbZA
  15. That's a shame - but a great credit to a retailer who's involved in the community and can quickly respond to such things. Based on this discussion, https://www.cloudynights.com/topic/42362-parabolic-v-spherical-mirrors/ the 80 should be close to 1/4 wave accuracy anyway, although the 100 is worse affected. But I doubt it will significantly affect enjoyment of the telescope and you can always try an aperture mask.
  16. It's almost certainly from the same factory as the Orion Skyscanner BL102, KSON in mainland China reportedly, but quite possible that FLO specified a parabolised mirror and Orion didn't. I note that whereas the full size Ursa Major dobs are budget option, these look a little bit premium compared to other mini-dobs, with the nice collimation knobs, longer focal ratios, and better eyepieces. The two comparisons I'd like to see. UM 80 vs Skywatcher Heritage 100P, same price. I predict the Heritage has the edge on deep sky but will the UM's collimatable primary and more forgiving f/ratio overcome its aperture drawback for lunar and planetary? And the UM 100 vs the Nat Geo 114, similar story. (The Nat Geo comes with rubbish eyepieces but let's say you buy an Astro Essentials Plossl as well and you're just a tenner above the UM.)
  17. The celestial equator appears to move 15 seconds of arc per second of time. Less if you're looking at something towards the celestial poles, but planets are always fairly close to the equator. The apparent size of Jupiter is between 30 and 60 arcseconds (roughly), so it will appear to move fairly fast on an undriven mount. If it's the Astromaster 114eq (and it looks like it) then sadly you've bought a bit of a stinker. The telescope optics, eyepieces, and mount are all dubious. If you're new to stargazing as a whole, focus on visual observing, and within that focus on deep sky viewing which is done at low magnifications which won't show the optical flaws so much. I would buy a 32 mm Plossl to help with finding things but I wouldn't spend any more on it. Understand that a better telescope could be a lot easier and less frustrating to use. To image the planets get your DSLR to take a video as the planet drifts across the view then process the frames. You can probably get a final image with some identifiable detail but do not expect very good results with this telescope.
  18. @catburglarI've noticed in my 105 that at high power the planet "jitters" as it drifts through the view. I wonder if you're getting the effect people talk about of the "cell size" of seeing that makes a larger telescope show more blurring while a smaller one has the entire view moving about?
  19. Congrats. Mostly Mars for me. Mostly at 150x, I wasn't really getting much at 250. (I could use a good 7.5 mm EP for 200 but haven't got one yet). An albedo feature in the south with a somewhat fuzzy north edge and another in the north just south of the polar cap, and sometimes they seemed to connect in the ... east (on Mars) I think. The rim of the planet seemed kind of bright. Overall quite reminiscent of the lunar maria to the naked eye, and a change from previous nights when I only saw the dark markings in the south. Tried my filters. They won't screw in so I had to rest them on top of the EP. The green and light blue *maybe* helped a bit, but really I think more time at the eyepiece brings more benefit than filters, I checked Stellarium to see if Jupiter was up to anything and saw the Ganymede transit was happening so diverted to look at it. Little dark dot on the planet clear as you like when the seeing wasn't blurring the whole thing. With a bit more time at the EP I made out the GRS, but fairly shortly back over to Mars. For me a night's observing isn't complete without at least one DSO, and a bit of back and forth between Stellarium and the telescope and I found M36. A bit sparse but a nice cluster with a prominent close pair of stars in it. All in the ETX 105 which I still haven't got the drives repaired on. Then in to warm my fingers. I was wearing some fingerless gloves so easy to handle the eyepieces and focuser but the cold does nip.
  20. I went 8x42 roofs, Hawke Vantage, for my new pair. Not used them a huge amount, I'd say they're not perfect but they'll do the job. Some ghosting on the Moon, but I get extra ghosts from reflections off my spectacles anyway. From what I've read hunters are a large part of the market for the really high end binos. We astronomers are not likely to spend £2,000 on a pair of 8x42s, we'd sooner spend £200 on the binos and £1800 on a telescope and eyepieces. That doesn't necessarily say much for the cheaper to mid range binoculars. The requirements are somewhat different - stargazing cares more about sharpness and control of stray light, hunting and birding care a lot about colour rendition and contrast - but I think a good pair of binoculars is still a good pair of binoculars whatever you use it for.
  21. That's a dramatic difference in size for two binos with the same "spec". Weight too, 750 vs 1150 grams. If you're going to use your binos mostly handheld and you don't have image-stabilised money I think it's worth considering the weight factor. On the other hand if you are OK with a 1.2 kg binocular, I wonder how the Stellar II 10x50 would compare to something like a 10x60 of similar weight and price?
  22. Thankfully the clouds stayed away for me. But I had to observe from upstairs indoors in order to see it. Not ideal, but I still haven't found a decent observing spot away from home. Viewing from inner city Birmingham. Viewed the approach and onset in the 4 inch Mak. Mostly at 50x because I was showing a family member the view, they observe with glasses, and I have a bunch of Plossls. I did get some looks at Mars at higher power and albedo features were visible in the south, but a serious effort on Mars will have to be another night, I have already had some good views this season. Moon looked great, the variation in tone of the maria was apparent, Tycho Copernicus and Eratosthenes very obvious and many smaller bright craters too. At 04:46 and again 04:50 I was able to see Mars with the naked eye by blocking my view of the Moon. I watched Mars recede behind the Moon in the scope at 04:58. I'll have to try and do proper second-precise timings next time there's a planetary occultation. My view of the reappearance was limited to using 8x40 binoculars. I conclusively spotted Mars at 05:58, and a minute or two after I felt I could see clear separation between the Moon and the planet.
  23. > Celestron Powerseeker 127EQ Widely regarded as one of the worst telescopes on sale. Lousy optics, lousy mount, lousy eyepieces, lousy finder. > Orion StarBlast 4.5 The tabletop Dobsonian version is fine, it's not widely sold in the UK though. The equatorially-mounted one ... I didn't get on with a Newtonian reflector on an equatorial mount because the eyepiece tends to end up pointing in silly directions and adjusting it requires rotating the whole tube (whereas with a refractor you'd only need to adjust the diagonal to get the eyepiece in a comfortable position). The "default" recommendation for £200 in the UK is the Skywatcher Heritage 130P.
  24. Just going by the pictures on FLO's website, if you buy an AZ-Pronto by itself it looks like you get the extension pillar and a better tripod? https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/sky-watcher-az-pronto-alt-azimuth-mount-tripod.html vs https://www.firstlightoptics.com/sky-watcher-az-pronto/sky-watcher-evostar-90-660-az-pronto.html
  25. Just a few minutes on the Moon with the binos, I feared the clouds might close in by the time I sorted a scope out. Copernicus (I think?) very prominent on the terminator and rugged terrain in the southern and northern highlands. I also like to see “the man in the Moon” as a footballer, fitting for the World Cup! Serenity, Tranquillity, Nectaris and Fecundity make up the figure and Crisium is the ball they’ve just kicked.
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