Jump to content

SkySurveyBanner.jpg.21855908fce40597655603b6c9af720d.jpg

Basementboy

Members
  • Posts

    204
  • Joined

  • Last visited

Everything posted by Basementboy

  1. Yeah I'm still at the stage where I'm perfectly satisfied with the "hits". As for the transit/shadow issue, I was so excited I forgot to count whether the number of moons had reduced to three. As it was a black dot, I'm guessing it was probably a shadow. Just as cool in my book
  2. After what I think I'm right in saying was five straight months in London during which it rained at least once every day, I finally got a chance to try out my TS Optics 115 triplet and 6" OOUK Newt under some dark (and warm!) skies in Suffolk for a camping weekend in the Ferrariat. The AZ5 having been successfully adapted to reduce vibration (thanks again to the SGLers who helped me figure out that the trick is to mount the arm vertically!) and the heavy SW 3/8 steel tripod heaved into place, I pointed the refractor at the big bright star low in the sky....... I had never seen Jupiter before. So that was pretty special. Four moons, at least six bands and what I think was a moon transiting across the surface?!?!?!? Or possibly a shadow transit. Anybody know how to tell? Saturn meanwhile was the whole reason I got into astronomy in the first place. It is the planet of my dreams. And in a telescope it looks exactly like a glow-in-the-dark sticker on a child's bedroom ceiling. It's like a comedy planet. Hard to believe it's real. I have to admit: it was Jupiter that was the better sight. It was huge and spherical and jaw-dropping. So there really is an unimaginably vast storm planet up there above us ... DSOs: Ring Nebula, Dumbell nebula, Whirlpool and Pinwheel. Swan was too low. First sighting of Andromeda, too, which I can't see from London and was, predictably, best at lower magnification. Great Hercules cluster was VERY cool, particularly in the Newt and at high mag (I've got a 5mm Hyperion that's dark but good) in the refractor. Dozens of visible stars and a real sense of the 3D clustery-ness of it. Only drawback was that I struggled to use the 9x50 RACI. It's almost TOO magnified for a relative beginner like myself: I got lost a lot. Am I the only person who finds the RDF sufficiently intuitive? All in all, a great time. Now to move to a country with better weather. I hear the Atacama isn't bad.
  3. Aha!!! Sorry for the delay, but I just got a chance now to try this .............. and it worked Well, mostly. It has reduced the vibrations noticeably. Some remain but it's a big improvement for such a small adjustment. I suspect it explains why the AZ3 was, somewhat surprisingly, shaking less – because the clamp is directly above the centre, so all the force goes straight down into the tripod. Whereas the AZ5, when angled out, has to bear a lot the force in the arm. So when it's readjusted into a more vertical position then the tripod can take more of the vertical brunt of the weight. A thousand thanks Top Team! Off tomorrow to Suffolk in the Ferrariat for some hopefully dark – and now less wobbly – skies!
  4. I suspect so – I play drums and the bigger ones vibrate longer
  5. Dastardly! Yeah I had considered the Skytee ... it's just a weight issue for me, given I need to carry my gear to the roof for any decent views. But – we struggle on ... Thanks John, appreciate it
  6. Damn, wish I'd spoken to you earlier. Although my frac is only 4.5" f/7 ... I remain somewhat surprised that the AZ5 can't handle it. But hey ho, you can't fool nature I suppose
  7. My setup is probably more like 7.5kg for the frac and maybe 6-ish for the Newt ... and I definitely did read several people say that the steel tripod should allow it to handle a few extra kilos. But maybe that was wrong ... or perhaps only applicable to shorter OTAs, eg a Mak
  8. It's F5 ... ie 750mm long. To be honest I didn't think that was particularly unwieldy, given that the Sky-Watcher Explorer 150 comes packaged with an EQ3. Or does the counterweight bar help in that case?
  9. Hi, I have a problem I'm hoping someone might be able to help me with. I am experiencing quite noticeable vibrations – a good 3+ seconds to settle fully after a minor tap or any movement of the telescope – on my setup. I have a TS Optics 115 Photoline apo triplet (OTA 6.5kg) and a 6" OOUK Newtonian (OTA 4.5kg). They're mounted on a Sky-Watcher AZ5, bought secondhand in seemingly very good condition, and a SW 3/8 steel tripod, bought new from FLO. The AZ5 reportedly takes a 5kg payload, but I have read that it should easily take 9kg with a good tripod – which is why I bought the steel tripod. I have tried tightening the screws everywhere, and I think I've got the tube rings squeezed on pretty tight. They're also reasonably centered, on both OTAs, and I've tried mounting the OTAs in slightly different positions – doesn't seem to make much difference. I'm not using any crazy accessories or grenade-like eyepieces – the biggest I have is a Baader Hyperion, but regardless I am experiencing the problem without any EPs inserted. The tubes just seem to kind of "twang". It's worst on the Newt. But even the refractor vibrates more than it did on my first mount, an AZ3, which I had written off as "bad" but now seems to have at least performed its primary function well enough. I thought perhaps it was the nature of a dovetail mount that a tiny screw, digging sideways into a metal plate, would be a "weak point" in terms of vibrations – but @Tiny Clanger points out that it's not really the screw that takes the force, but the plate opposite, which spreads it out. So I'm stumped. Any advice gratefully received 🙏
  10. The OP was asking about visual observing, not photography – what they could see, and whether it's worth buying a telescope to see it
  11. Thanks Don. Great list, regardless. I recall reading an essay of yours in which you tried to develop a ranking of, shall we say, easiest/nicest DSOs to observe? And concluded I believe that there was no easy method
  12. Just posted about this on another thread, oops – but to recap (aptly enough): I thought it was good – a snappy flip back through some of the best bits of his previous programmes, many of which I hadn't seen, updated to reflect the latest scientific understanding of what he was talking about back then. I find him much less annoying than I did 10 years ago, too, so that bit at least has changed
  13. Anyone catch this? I thought it was good – a snappy flip back through some of the best bits of his previous programmes, updated to reflect the latest scientific understanding of what he was talking about back then. I find him much less annoying than I did 10 years ago, too, so that bit at least has changed
  14. Very cool. Thanks, both of you! It works OK for me in Open Office, although slightly glitchy when scrolling down – the numbers blur into each other. But it soon appears to realise, and sorts itself out. Now if only there was a column ranking for "easiest to see in Bortle-9" ...
  15. While I agree that randomly scanning the skies is fun, I think the problem is that it's definitely more fun in dark skies, when there's lots to see. In light polluted skies, there aren't many objects easily visible. So you'll probably spend a lot of time seeing "nothing" – ie, no special objects – although of course just scanning the stars themselves can be entertaining. For a bit. But that doesn't mean you need Go-To, either ... a good finderscope and a book like Turn Left at Orion (which I've used) can help find some of the easier things to see in light pollution, like globular clusters, open clusters and double stars – things you're very unlikely to "stumble" across when the sky is washed out
  16. I'm in a very similar situation, and although still a relative newcomer to this pursuit – so take what I say with a big grain of salt – I have learned a few things you might find useful. I live in a relatively central bit of London, classified as Bortle-9 (the worst of all Bortles) for light pollution, and to make matters worse the roof of my building is only three storeys high, meaning I am surrounded by the light of nearby apartment blocks, some of which glare all night long. (No patio lights, at least!) To start with the good news: the planets are so bright that they shine right through the light pollution. (In fact the Moon is sometimes so bright that it becomes, after the city glow and nearby lights, the third source of light pollution, washing out the whole sky.) You'll get breathtaking views of the Moon easily. Mars is the next closest object, but considered tricky to get much detail out of – but as long as you don't expect too much (no Martians!) you'll be able to see it as an obvious disc or (with some imagination) even a sphere, and possibly identify the polar caps: though think of that as an future observing goal rather than an immediate possibility. You should also be able to see detail on Jupiter (banding) and Saturn (ie the rings, and maybe the Cassini gap between them) – although unfortunately they're below the horizon (at least at London's latitude) right now, and only rise a few degrees above the horizon this summer. This raises another big problem with city light pollution: it obliterates the sky anywhere near the horizon. So your best bet is to look higher up ... which is often where the planets are not. What is up there? Among other things, galaxies. But here's the bad news: Galaxies (and nebulas) are tough in light pollution. They're faint. Normally the solution with faint things is to get a telescope with a bigger aperture, to collect more light – but in major cities, more light also means more light pollution. People have told me that anything above 6"/150mm can be a problem in this regard, with the tradeoff between extra light and extra light pollution becoming no longer worthwhile. If your city is very bright, you'll be very lucky to see galaxies as anything other than a very faint smudge, I'm sad to report. As for nebulas, the Orion nebula, at least, is quite bright so you'll be able to enjoy seeing it (and the "trapezium" of 4 stars at its heart), but nowhere near as well as you would in darker skies. The other very annoying thing about trying to find faint objects in light pollution is that even locating where they SHOULD be is hard, because the sky is so washed out that it's difficult to navigate. (You can get around this by using a Go-To mount, so at least you'll be 100% sure that you can't see that galaxy.) So what CAN you see? -Star clusters. These are things like the Pleiades or the Beehive: sparkling groups of neighbouring stars, which can look very beautiful and are relatively easy to find. -Globular clusters. Unlike other DSOs, these faint fuzzies (tens or even hundreds of thousands of stars in a tight ball) are comparatively bright, and visible as glowing fuzzballs. (With good telescopes you can start to resolve individual stars.) -Double stars. Personally I've never been too excited by double stars, although they are beautiful in their own right (different colours etc) and a nice "challenge" to split ... though ultimately you're still only seeing two points of light instead of one. Long preamble leading up to your question about what telescope to get: Caveat: I don't have an answer. Every telescope does some things well and others not so well. But you can narrow it down a bit ....... To start with, one thing that DOES help (at least a bit) in light polluted skies is contrast: the difference between dark sky and light object. Refractors give excellent contrast. But big refractors also produce some colour distortion ("chromatic aberration" or CA, visible as anything from a purple fringe that I think looks fine or even appealing, to a more bizarre, almost kaleidoscopic wrongness on very bright objects like the moon ... maybe this is why people used to say it was made of green cheese?) You can avoid CA – and get better contrast, too, theoretically improving views through light pollution – by purchasing an apochromatic refractor, but they're expensive. As in, exponentially more expensive per millimetre of aperture. Newtonians/Dobsonians are a much cheaper way to get more aperture, but we know that more aperture can be somewhat counterproductive in bad light pollution. And the contrast isn't as good. So while normally they are a terrific choice – the Heritage 150 tabletop Dob gets great reviews – I think they're less of a winner in very bright cities. Maksutovs are great at planets and the moon. So if you want to prioritise them, a Mak is a good choice. The downside is that it's more difficult to navigate with Maks because their long focal length means you get a very narrow field of view, which means it can sometimes be hard to know for sure which specific bit of sky you're actually looking at, extremely annoying when the sky is light and you can't identify star landmarks and you're just lost up there. (But again, a Go-To mount will solve this problem. Or get a good finderscope, eg a 9x50 ... a simple RDF won't cut it.) Maks will also make some objects like globular clusters look less bright, but that's less of a problem with moon+planets because they're already so bright to begin with. They also aren't as good on wide star clusters (Pleiades etc) because they're quite narrow and not as "contrasty" as refractors. Lastly, as I'm sure you know, they need to cool down for a while to work best. SCTs I've never used, but they're a similar design to Maks, so would, I imagine, have similar advantages and disadvantages for visual observation under light pollution. So, again, long way to get to your original question – what telescope should you get for fighting through light pollution? Well, a good bet is a Mak (or SCT) to focus on what you CAN see well through light pollution: the moon and planets. The Skymax 127 is one option I've tried and liked. Just bear in mind that the Moon and planets aren't always visible (and some planets stay hidden for months) and that navigation can be a little difficult without Go-To and that they require some cooldown time. Or get a similarly sized refractor (eg the Startravel 120, even the bigger Altair Starwave 150 if you can handle its huge size) to get nice wide views of star clusters, split doubles a little more easily and maybe stand a tiny bit better chance of resolving faint fuzzies. Just bear in mind that views of moon and planets won't be quite as good as Maks, and brighter objects like planets can have some problems with colour and sharpness. (If you have lots of money you could get a 6" apochromatic refractor for the "best of both worlds", but these can be thousands of pounds, before you even start buying accessories like eyepiece upgrades etc – and you WILL buy accessories.) Regardless, either get a Go-To mount or a good finderscope that actually magnifies (at least 6x30, recommend 9x50) so that you can navigate the haze. Three other points: 1. Light pollution filters are considered a bit of a waste of money because they are designed to block out the light from sodium streetlights, but many cities now use LED streetlamps, as indeed do most car headlights, apartment building lights – and I would imagine your automatic patio lights, too. A filter might help reduce the skyglow a little bit but don't expect much. 2. You'll find plenty of nice things to see if you keep your expectations realistic – which it sounds like you are, so that's great. 3. Wear a hood. Good luck, Chris
  17. Oh man, what a disaster – my commiserations! I feel somewhat guilty being in possession of your 4.5" frac now, but I'm glad you've got insurance covering at least part of it and it sounds as though this has only deepened your commitment to your burgeoning relationship with fluorite. After The Floor Strikes Back and A New Hope, I look forward to seeing the third and final instalment: Return of The Takahashi
  18. Clear at last! Though London continues to shine with the heat of a thousand suns
  19. And the cost of the staples. Don't forget the cost of the staples. (This is truly excellent.)
  20. I bought @Commanderfish's TS 115 and I like it so far. Can't comment (yet) on the views in any great detail, as I've only had a day without cloud to try it out. But it's got great build quality with an excellent focuser, and, crucially, it's fairly short (800mm F7, only 71cm w dewshield retracted). As a result I was surprised to discover it actually sits on my cheapo AZ3 mount without TOO much vibration (maybe 1 sec). I'd definitely want to upgrade the mount soonish, but the point is that it's relatively compact for its power and well balanced, so you shouldn't need a huge mount for it. Me too, as I'm also in it for visual use only. But there weren't any going secondhand and my budget was £1k including a couple of decent EPs. For the sale price TS Optics have it up for right now (under £1k, brand new!), it seems to be a great deal for a 4.5" ED triplet. I also figured it should have decent resale value, given it would also be a good imaging telescope option for our astrophotography-minded comrades. Whether it would arrive on time in the UK from Germany during these strange times, however, I couldn't say
  21. Right, makes sense, thanks Not to mention something to look at when almost every night is cloudy
  22. Nice! And that's it? Just a bit of Baader solar filter between your eye and Sauron's? I thought you needed fancy "solar scopes"... That's one reason why I like this forum so much, you say "I'm thinking of buying this" and someone says "nah just sellotape a cigarette and wrap it in an elastic band and you'll save yourself four thousands pounds"
  23. Here's an admission of stupidity – I didn't realise you could use something like an ST80 (which I own, too) to look at the sun. If you were able to share links to the equipment you bought, I'd be very grateful
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.