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Giles_B

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Everything posted by Giles_B

  1. I finally found my 'cheap enough' second hand 10" Dobsonian with a computerised star map (a Orion10XTi Intelliscope) and, after some predicable initial teething problems on the first clear night, took it out for its next spin, in my (Bortle 6) garden last night. I found the Intelliscope hard to use, and not much help finding anything. I think this is probably a case of just going through the manual carefully, and having a better sense of what to look for in the huge database. Luckily I've attached my trusty Starsense Explorer phone mount onto a piece of 8mm acetal, screwed this to the tube rings and it works a treat at finding my way around. The bigger worry is that the optics just didn't seem to be performing as I'd expected. As I say, the moonlit night was light and I didn't have great expectations. I found my BST explorer eyepieces had hideous coma (the scope is f4.7) - even the 18mm which I'd heard tell was fairly good in a fast scope. I fell back on a couple Baader orthoscopic eyepieces. These are never quite as twinkly as the BSTs, but I had decent views of Pleiades and the Beehive cluster. However, even given the unfavourable conditions I was very underwhelmed with the view in comparison to my 5" Celestron Starsense 130 newtonian. The Orion Nebula had a little more detail - but only a little. I couldn't even make out Bode - not unusual on a bright night for my 5", but I'd had high expectations given the extra 5" of aperture. My fears that there may be something fundamentally shot with the optics are already heightened by the fact I spotted a small crack at the edge of the primary mirror while collimating. The jury seems out on this looking through the forums (that is, there are many voices of doom and a few saying wait and see if it is the crack is stable), and I'd decided to wait until I had better eyepieces before deciding the coma was due to this. However, I'm now wondering if the unimpressive views may be due to some degradation of the mirror. Now, I'm a novice, and all I have to go on is the views I'd come to expect from the Celestron 5", so my question is: I am just in the process of having my high expectations of 10" performance reduced, and essentially doing the right thing patiently waiting for some high end eyepieces to be back in stock in the UK, or are there so many red flags that I should I be thinking about a new primary mirror sooner rather than later, to improve the performance with my current equipment?
  2. Hi Jammy G, I'm about a year in on a similar trajectory to you - I've got a Celestron 130az - so a slightly bigger reflector, but 102mm should allow you to view quite a lot. I live in the city with quite light polluted skies (Bortle 4-5). The Starsense app works well despite these conditions and will direct you to the brighter objects in the sky. I tend to get interesting views of planets, open clusters and bright nebula. Unfortunately Saturn is pretty much too low to see now, and Jupiter is getting lower in the sky, but should be visible just after dark. Try looking at Pleiades to get a taster of open clusters and there are good views of the Orion Nebula at the moment - but there are many slightly less bright, but nonetheless fascinating, objects on the Starsense app. One thing I'd recommend getting are some new eyepieces, because the ones supplied with the starsense scopes are terrible. I began with Baader Classic orthoscopic eyepieces, which were okay, but moved onto BST explorers, which were much more satisfactory, after advice on this forum. The eyepieces really make the experience, the view of the moon and planets is far superior and they change open clusters from dull "dots of light" to something much more structured and spellbinding. Good luck!
  3. Thanks for the tip on the Stellalyra. it does look very well specced, and the push to looks like an interesting option. It sounds like a lot if the difference is about features rather than anything fundamental with the optics. I have noticed all these scopes come up on eBay from time to time, which is another way of saving cash for good eyepieces - are the optics pretty similar for all the different models if one came up at significant discount?
  4. I'm looking for a 10" Dob to upgrade from my current beginner set up (Celestron Starsense explorer 130mm newtonian). I've narrowed the potential range down a bit, but I'm getting a bit confused between the options. These seem to be Skywatcher 250PX https://www.rothervalleyoptics.co.uk/skywatcher-skyliner-250px-dobsonian-telescope.html Orion XT10i https://uk.telescope.com/Telescopes/Orion-SkyQuest-XT10i-IntelliScope-Dobsonian-Telescope/rc/1306/p/109949.uts Bresser Messier 10 https://www.bristolcameras.co.uk/p-bresser-messier-10-inch-dobsonian-telescope.htm The technical points of difference seem to be: Skywatcher 250PX - crayford focuser (has some recoil), teflon bearing Orion XT10i - crayford focuser, nylon bearing, cheap base, Push-to system Bresser Messier 10 - hexfocuser, generally better construction, upgradable to equatorial mount, teflon bearing The other big difference is price and availability: the Skywatcher is around £550 and everywhere, the Bresser is about the same and difficult to find in stock, and the Orion seems to be pretty rare and is nearly £1000. -now, I am attracted to the push-to on the Orion XT10i (given I am migrating from a Celestron starsense) but I am not sure if it justifies the potential lead time and huge cost difference (I am anyway planning to adapt the starsense explorer phone adapter to the new scope): are there technical differences I am missing? Any advice gratefully received
  5. Our understairs cupboard is overflowing, so it's the shed or nothing, for now anyway (I may get rid of the Celestron at some time depending on the ability of the Dob to travel). The added bonus is that a scope in the shed raises will be easier for my partner to ignore. She's already made it clear she isn't on board with me turning the place into the next Greenwich Observatory... sigh.
  6. Is it worth getting a special cover like this https://www.firstlightoptics.com/telegizmos-telescope-covers/telegizmos_tg2d.html ? Any desiccant packs you'd recommend?
  7. I'm considering my telescope upgrade having reached the limits of my current Celestron 130mm newtonian. I'm thinking a Dobsonian is the most affordable route, although not yet quite decided on the make and size. Our house is pretty crowded and so I'd plan to store this in our garden shed (which is dusty but dry). I wondered if there was any downside to doing this, for example, do the bearings and focuser get rusty or stiff, does the mirror get mouldy etc. etc.? If there are issues, I'm not beyond some routine maintenance (i.e. cleaning, greasing and oiling, but are there any special steps I should be taking to keep a shed stored scope in good condition? One final thought is about security. Thefts are uncommon, but not entirely unknown where I live. I'm assuming a reasonable sized Dob would not be an attractive proposition to a thief (heavy to shift and difficult to sell), but I'd be interested to hear your thoughts and wisdom.
  8. Thank you, but if you saw my standard of carpentry you'd think twice about the advice. If I can get away with £15 for a bar, that will save a lot of grief!
  9. I agree. I'm not quite a year into observing, but it just gets better and better. Part of this is getting the right equipment, for me, part of it was calibrating my expectations: once I realised the limits of what I can see I could stop trying to recreate the hubble telescope in my back garden. I bought my scope wanting to see the planets, but I more and more I've found myself drawn to the DSOs and Open clusters. The latter get a lot better with good eyepieces, you can see a lot of intricacy that isn't present otherwise. DSO are just so mysterious they draw me in. Also have a look at the emission nebula in Orion. There is so much to see, so don't give up.
  10. Pleiades is fantastic - find it in Taurus - and the beehive cluster in Cancer was a nice find for me last week. Great to have some clear nights again after all the cloud over Christmas.
  11. Excuse the stupid question, but is dovetail bar the same all over? I'm astounded that it can vary in price so much. Dovetail bar seems to range from just over a tenner for something generic, to £70 or more for something exotic. Am I okay getting cheap bar or is the cheap stuff is cheap for a reason... Has anyone advice or cautionary tales? If it's helpful, the bar only needs to hold about 600g in weight - I'm thinking about moving up and on from my Celestron Starsense Explorer 130az, Inspired by descriptions on this forum and elsewhere I'm looking for dovetail bar to help fashion something to attach the Starsense phone dock to a setup (not sure what scope, still thinking about my options there, so this is kind of a 'proof of concept stage'!).
  12. Really glad you are enjoying it - sadly a combination of a heavy work schedule and the constant rain has meant I've been out less than I would have liked over the past week, but I agree the app and the portability factor are real marks in the Celestron Starsense's favour. I think the only thing I don't enjoy about the scope is its rather wobbly nature - it always takes a good 30 seconds to settle down if I adjust it - so you can just imagine the problems when I tried to show my 5-year old Saturn a few weeks ago - she just couldn't look without grabbing the tube and told me Saturn looked like a "wobbly dot"!
  13. Thank-you very much for these responses and apologies for my delay in replying - I guess picking up my scope and getting out of town is the best, and maybe I'm just getting over influenced by catburglar's recommendation, but I think I may start to seek out some emission nebulae with a view to getting an OIII if I can get a reasonable view (i.e. not obstructed by trees and houses from my garden) - there's nothing like the convenience of observing the sky from my backyard
  14. It was a wonderful clear night in Bristol last night. I got some great - really great - views of Jupiter and Saturn - the atmosphere seemed crystal clear and they were probably the best I've managed since getting my scope, a 130mm Newtonian (Celestron starsense explorer 130AZ ). Once again I was also draw to deep sky objects which I find fascinating (despite the light pollution of a big city). You can't see much from my garden, but I spent a good time looking at the Andromeda and the Hercules cluster. The view is very faint, and it is difficult to make out structure. I understand, thanks to discussions on SGL, that this is normal for visual astronomy and not helped by the limitations of my location and equipment. While I'm content to persevere, I wondered if it would be worth getting any (more) filters for my set up. I have a moonlight/city light filter, which doesn't seem to do much to the view when I combine them with my 25mm BST explorer eyepiece, but I have read (I think) that some coloured filters can improve the view of DSOs. Is it a pointless waste of my money to add filters when I could get a much better effect by driving 20 miles outside town to somewhere with less light, or would filters be worth it? If so, can anyone recommend 1.25" filters that won't break the bank?
  15. Indeed, this suggests the "interview" quote was probably from a press release (standard practice for science reporting) - so the Royal Observatory rather than BBC is probably the institution to get annoyed with / complain to....
  16. @Louis D It sounds like an advance on an Ikea bag and a couple of towels wrapped around the tube, which is what gets me by
  17. There might be a cheap solution that is a step up from duffell bags and bubble wrap if you don't see a special advantage in spending £££ on a bespoke case. If any padded bag of the right dimensions should do the job - a quick google for "padded bag" using the dimensions of my scope (a Celestron 130mm admittedly much smaller than yours) showed this might just do the job: https://www.terralec.co.uk/padded_bags_and_covers/padded_equipment_bag_762_x_356_x_356mm/28075_p.html - I just wondered if there might be something similar that would suit you, that could be found with a bit of searching?
  18. Thanks John, I'll be looking out for these sessions! Tiny Clanger - you may be right, my experience of DSOs may be a repeat of my initial "isn't Saturn small" experience... I'll check out the guide
  19. Thanks for talking me through this - it is really helpful and deepening my understanding. It is a bit embarrassing to be making mistakes like confusion the focal ratio with the aperture (thanks for pointing it out), but it's a fast way to learn. So far my best results have come from appreciating the strengths and weaknesses of my current set up and it is easy to overlook the part the portability of a small scope plays in getting good views, well away from my neighbours security lights! Unfortunately my budget won't run to EEVA, but I'm certainly interested in the BST eyepieces and can see from this forum they are well respected, so I'll check these out for the high magnifications. I'll stick with the Plossi for DSOs for now.
  20. Thanks for these replies, and the tip on open star clusters - I'll try these next time I get some clear skies. I don't think I explained myself well enough about magnification and switching to 2" eyepieces. I think I understand that 2" will offer low magnification and a wider field of view and perhaps better eye relief. I'm interested in the wider field of view of 2", but would also like to be able to use 2" eyepieces at high magnification (when viewing the moon and the planets). The most economic way of doing this could be by combining a 4x Barlow with a medium focal length eyepiece (20mm or less), but I'm concerned the weight may be prohibitive. However, as moving to 2" would also in part be with upgrading to a larger scope in mind, I'm interested to hear that I'd be unable to visualise galaxies clearly without delving into astrophotography. Would this still be the case even if visualising through a high aperture like an f12? Sorry if this is a silly question, just wanting to make sure I get this right.
  21. I am new to astronomy, getting my first scope, aCelestron Starsense Explorer 130az (f5, 130mm Newtonian) about 3 months ago. This is my first post, apologies if it is a bit long or misinformed. I've upgraded the eyepieces to Baader 6 / 10mm orthoscopics / 32mm plossi, plus a Celestron 2x Barlow, all at 1.25". I've had satisfying views of Saturn, good views of Jupiter, plus some great views of the moon. I live in the very light polluted part of a city, but have managed over the holidays to get to some darker skies, however even in dark skies I've been disappointed with the views of brighter DSOs like Andromeda and Bode, which appear as cloudy puffs of dim light, with no resolvable detail. I understand I'm not going to get good views of DSOs on an f5 aperture, so eventually a new scope will be needed, but I'd like to get more out of this scope if I can. I'm thinking of upgrading the eyepieces further. With a view to greater eye relief (I find the high magnification orthoscopics uncomfortable) and use in a future scope that is suited to DSOs I'm considering getting some 2" eyepieces. Ideally I would like to use them for high magnification if possible. I've been looking at eyepieces from Explore Scientific 82° range, or the Celestron Luminos range. For magnification I'm wondering if it is worth splashing out on the Televue 4x powermate. My concerns are firstly, whether a 2" plus a Barlow will be too much weight for the Celestron explorer - the televue plus a luminos would be about 900g - I'd be interested to hear your thoughts and experience. Secondly, I'd be interested to hear your views on a move to 2" eyepieces more generally. Is it a sensible upgrade path or should I be looking for better 1.25" eyepieces instead? and will any brand enhance my views significantly over the Baaders, or is the f5 ultimately the restriction here?
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