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Found 97 results

  1. I've decided to sell my beloved Skywatcher Skyliner-250PX FlexTube GO-TO Parabolic Dobsonian Telescope. It's in impeccable condition, and is absolutely superb. I still have all the boxes, instructions etc. Plus it comes with an Astrozap Light Shroud and accessories! All of which are in excellent A1 condition. As some of you know already about the Skywatcher Skyliner-250PX FlexTube 254mm (10") f/1200 SynScan GO-TO Parabolic Dobsonian Telescope. Combining the power of a large optical tube, the extreme portability of the patented collapsible FlexTube design and Go-To technology, the new Skyliner FlexTube Synscan Dobsonians bring over 42,900 celestial objects right in front of your eyes, and automatically track them as they move across the night sky - its as easy as a walk in the park! The patented dual-encoder design allows you to manually move the telescope anytime and to anywhere you wish - with no need for realignment. Slewing to an object on the opposite side of the night sky no longer feels like watching a kettle boil. Simply push the button! I'm selling as we require the space (excuse the pun) for a little one! Sky-watcher Skyliner-250PX Features: Magnifications (with Eyepieces supplied): x48 & x120 Highest Practical Power (Potential): x500 Diameter of Primary Mirror: 254mm Telescope Focal Length: 1200mm (f/4.7) Eyepieces Supplied (1.25"): SP10mm & 25mm Dual-Fit 1.25"/2" Crayford Focuser Parabolic Primary Mirror 0.5mm Ultra-Thin Secondary Mirror Supports 9x50 Finderscope Direct SLR Camera Connection 3-Point tube locking system, fully retractable Alt-Azimuth Mount with Accessory Tray and Built-in Heavy-Duty Servo Motors Go-To Handset 42,900+ Object Database containing full Messier, NGC and IC catalogues Quiet operation Power Requirement: 12v DC Power Supply (Tip Positive). Sky-Watcher 17Ah Power Tank Recommended 56% more Light Gathering than 200mm Cash On Collection. The scope plus light shroud and accessories is easily worth over £1k. I am seeking £800 ONO. I'm in Surrey. If you're interested just drop me a line! via PM please. Regards, Telrad
  2. We decided to build a shed to house our Dob, which was taking up way too much house space. As to design, @ollypenrice suggested that we build a large 'skateboard' upon which we should sit our shed. The board is made from a sheet of plywood onto which the wheels are mounted. The wheels we chose were the ones used for sliding gates (we have something similar on our roll-off-roof shed. Here is the shed on the rails. The rails themselves were mounted onto concrete, steel reinforced lintels which were concreted into the ground: A slot is cut into the skateboard to allow it to fit around the base of the Dob: It seemed sensible to put down some sort of circular patio, and we discovered that you can buy kits. It was a little awkward cutting the slabs around the tracks, but I am happy with the final result: Before After And finally, the completed project with Dob in situ. We used a green strap - the thing you use to keep your suitcase closed - to stop the Dob from rising up in the shed (without an eyepiece it is a bit rear heavy): We chose materials for the shed that would match those of our existing ROR observatory (from Home Observatory UK - https://stargazerslounge.com/topic/245177-home-observatory-uk/):
  3. I decided to try imaging Jupiter for the first time last night - this was the result. Nothing spectacular, but it's a start I guess! I'm wondering if anyone can give me any tips on how to get more detail? I took this using a Canon 70d attached to an 8" Dobsonian at prime focus 1 x 30 sec video Stabilised in PIPP Stacked in Registax Wavelet adjustments Am I missing something? I mean, I'm happy with the result considering the video was terrible, but I'm sure there's something more I could be doing. Would adding a barlow lens give better results?
  4. Hi Everyone, I've a 12" Skywatcher Collapsible Dobsonian and recently purchased a Moonlite Crayford Focuser for Reflectors. It came with .5" adapter & 1" adapter. Could someone please advise on which way the installation should occur. I am not sure if I need to only use the .05" or the 1" or use both. Secondly, which way should the adapters be mounted. Should they be mounted such that the 1" number appears in the top left, meaning the curved part on the top or bottom? also should the focuser be placed such that the dual knob comes on the right or left? Any advice is greatly appreciated. If someone has a similar design please let me know! Thank you! Clear Skies
  5. Good day to all who come by this post. I have a old 10 inch Dob that i made about 7/8 years ago that is rather knackered after so many nights observing. The scope was not very well made as it was my first attempt at building one. since then ive lern't so much, building about half a dozen scopes. Especially after building my 20" and reading David Kriege and Richard Berrys book The Dobsonian Telescope. Which i highly recommend. As you can see from the image attached the old scope was based on Obsession telescopes, Ultra compact design. the secondary cage was originally one ring with the spider protruding up like a pyramid. i decided to change this to a fully enclosed cage dew to stray light and wanting to mount dew controller and other things to it. Also another thing that ive not seen on any other scope is all the axes ran on bearings this worked really well but Teflon and formica is just as good if not better and i find its easier to get the scope balanced. I also used telescopic camera tripod poles for the poles this was sometimes a hinderance as i would have to re collimate a couple of times during the night. All in all the scope worked fairly well and ive had so many fantastic nights with it but its time to rebuild. I had some materials left over from the 20 inch Dob build and ive spent about £100 on new hardware and poles. I gave the mirrors a good clean the other day they are in good condition with no sign of ageing. The rebuild will be very similar to the 20" so it will be like a little brother to the 20" The build is imminent so will post update very soon Thanks for reading. Pete
  6. Hi again About 2 years ago i built a 4.5 inch ultralite fold out travel / hiking Dobsonian. weighing in at about 2.5 kilos with eyepieces, collimator and tools. Here is a link to a Thread about the 4.5 Dob - http://stargazerslounge.com/topic/237230-45-compact-travel-scope-for-hiking/?hl=compact This works well but i always felt i could get it lighter and more compact when packet down also me loving building scopes so much i will find any excuse to build another one. This time i have decided to go all metal. Mainly using Aluminium. i want to design the dob as minimal as possible. All i need to do now is design the mount. probably something very simple. here are some plans and some of the build so far. thanks for reading. Pete
  7. From the album: Scope & Equipment

    In my search for Comets at the moment, I had a night outside on a clear evening last week. I cannot wait until Comet ISON makes it's way round.
  8. I have had my 300P dobsonian for nearly a year now, and it has occurred to me that I finally may be qualified enough to write a review about this little beast. I think it would be good to avoid details on how it was delivered or what accessories I have bought for it. Similarly, I will not spend much time discussing how it performs when observing in detail, because that belongs, I believe, somewhere in the observing section. Anyway, as you might have guessed, Skywatcher Skyliner 300P dobsonian telescope is no midget. Simply put – it’s big. Its OTA is big, its dobsonian mount is big, it weighs a lot, it’s pretty hard to handle; pretty much as you might expect. I reckon that having a 12” dobsonian (solid tube) is the reasonable maximum for one person (albeit strong) to handle. With smaller telescopes, like 4.5” or even 8” ones, transportability of such device is not really a primary concern for most people, but when it comes to 12” and larger, moving the thing about can really become an issue. Luckily for me at least, I am – I like to think – a strong person, so I had no problem to devise an ideal transporting procedure when I want to take this baby out for observing. I am fully aware that the primary concern when moving a telescope is its weight – I am afraid that I do not know the exact figures of 300P, but if I would guess, I would say the telescope weighs some 40 kg (sorry about the metric), with distribution being 50/50 mount/OTA, but I cannot be sure. I have described my first impressions of the scope here: Skyliner 300P dimensions: Base diameter: 64 cm Base (mount) height: 78 cm OTA diameter: 35 cm OTA circumference: 114 cm OTA length: 144 cm "Parked" position height: 160cm Total weight: A lot! (cca 40 kg) Optics The heart of this puny thing is a parabolic primary mirror of 305 mm diameter (12”). It is actually pretty funny because the secondary mirror is therefore roughly the same size as the primary in my Firstscope 76 – this thought always makes me giggle. Well I know that there are plenty of you using larger scopes than 12” and those of you who do have my sincerest admiration, but I reckon 12” is the practical limit for me and probably always will be. Anyway, the primary has a focal length of 1500 mm, which means that even though it is an F/5 scope, its OTA is quite big, being some 140cm in length. The secondary mirror is held in place with a four-vane spider assembly, which allows you to adjust its position in all four directions to make it as dead centre as possible. I have also heard that it is best to have the vanes tightened like a string, but I am not sure about advantages of this one. When observing bright objects or stars, you get the traditional diffraction spikes, as expected. You can adjust the secondary in all ways and direction imaginable, but the great thing is that once you do it properly (so that, say, a laser beam from a laser collimator is spot on the primary centre spot), it does not move at all, even when you treat the scope roughly, so you might not need to adjust the secondary for quite some time, which is quite good, given the size of the secondary mirror. The primary mirror, being as heavy as it is, does not hold its collimation that well so tweaking it once in a while (I check it every time I head out) might be good. I should note that the primary mirror cell has pre-prepared holes for one 80x80mm fan in the back, for mirror cooling, which I think is handy, and easily exploitable. One thing that might present a problem is that it’s F/5 scope, meaning that it’s quite demanding on the eyepieces. Me, personally, I am not a perfectionist, so somewhat blurry stars on the edges of the field of view don’t bother me, but I can see how that might be a problem for some people. Anyway, there is not really much you can do about, except for whining about it, or buying an eyepiece that almost matches the price of the entire telescope. Take your pick. The focuser is a classical Crayford 2” focuser, which I think works quite well - you can adjust the tilt of it, and it is really firm and solid, even when you use pile up optical elements on top of one another. I bet there are better focusers for the job, but for me, using the scope purely visually, it works a treat. You can even fit it with a standard Synta motorized focuser, which makes the pin-point precise focusing (on planetary and Lunar observing) even easier. OTA The OTA is made of metal, and pretty much all of the OTA (primary mirror cell, focuser, etc.) are made of metal as well. Only thing made of plastic that I can think of are the two barrels supporting the OTA as it sits on the mount, and they are the weak spots of this scope’s build quality. The plastic parts touch the metal tube, which results in occasional squeak and creak now and then, which can get really annoying. Apart from that, it is all quite pleasantly well made. Of course, when considering the OTA’s shape and size, it all rather resembles a large dustbin; this means that every knock on the OTA gets amplified and it all sounds a bit too hollow, or tubby, which on one hand does not really feel assuring regarding the scopes build quality, but on the other, it is a great tool for scaring away stray wildlife at night - you just knock on the OTA and they are gone. I am given to understand that wildlife is scared by unnatural sounds, so this one fits the bill nicely. The finder scope is located in quite a convenient place, but I can’t really comment on using the default straight-through finder, because I have immediately replaced it with an RA finder (same spec), but I can see that using the default finder may get a bit awkward when you try locating something near the zenith; there is no problem with my RA finder in this area. Furthermore, the size of the OTA leaves you enough room for additional accessory to be mounted on - I myself have mounted a red-dot finder on it, as seen in the pictures, but there will definitely be no issue in trying to fit something like a Telrad or Rigel finder to it, or, indeed, using a small refractor for a finder (but you have to keep an eye on the OTA’s balance. Furthermore, the default matt black paint with which the inside of the OTA is painted, is really not bad, but I have taken the liberty of flocking it already link here: ) - I actually don’t believe it helps a great deal, but it is good to be able to exploit the performance capabilities of the optical system to the limit, and flocking can’t do any bad. Naturally, the OTA itself functions as a “bulletproof” dew shield for the primary, but surprisingly, you can get the secondary dewed up - it happened to me once, it was really unexpected, even despite the heavy dew-fall, and when this happens, all you can do is pack you stuff and call it a night. One thing that really bothers me though is the dust cover for the OTA - when it’s cold outside (and it usually is), it probably shrinks which means that when you pack your things and head home, the cover keeps falling off of the OTA, which is really annoying. Dobsonian Mount The OTA sits on a dobsonian mount - very basic, totally functional. It is made of chipboard material, and when I built it together, I was worried about it swelling up from water, so I glued all parts together, leaving no slit uncovered for water (dew to be precise) to get in it. What was surprising for me was that despite the fact the online description said the mount would come with Teflon pads, it came with roller bearing instead (for azimuth axis). It was quite a pleasant surprise, thought I reckon there was a mistake in the description in the first place. The OTA is cradled on four plastic knobs, two on each side, which works quite well, although sometimes, the resulting movement in the altitude axis stammers a bit - I have seen some DIY modifications, where people replaced the knobs with ball bearings, and I think it might be worthwhile, but for now, I will go with the default setup. There is even a shelf for your eyepiece with holes in them (three for 1.25” and one for 2” eyepieces), which seems nice, but for me, it is in a rather awkward position. Once the warranty is void, I can feel modifications coming, primarily in the mount area. Transporting it The OTA sits on a dobsonian type mount, which is made from chipboard, and there are only two hand screws (functioning as tension screws) that hold the thing together. So when you remove the screws, you can move the OTA and the mount separately. It is good to grab the OTA by the primary mirror cell at the bottom with one hand and support it at least 2/3 of the way up with another – that way, you have quite a good firm grip of the thing. Only thing you really need to be careful about then are doors (for obvious reasons). When I head out observing by car, I usually load the OTA first. Now with our Megane estate, it is not a big deal – I just fold one of the back seats down, and lay the OTA in gently through the boot, and eventually secure it in place with a seat belt. Initially, I was worried about scratching the thing when moving it so I wrapped it in a bed sheet, but it has proven unnecessary, and even dangerous that it might slip out of the sheet. When I transport the thing by a small hatchback (Clio), the things get a bit tricky – I have to fold down the front passenger seat and remove the rear seat to let it fold flat. Then I place the OTA on the front passenger seat and secure it with a seatbelt. I think that you can see the catch at this point – no company when observing; and, it is useless to try and load the OTA transversely, because it would not fit (unless you have a Hummer or something). So I can see that transporting the scope with a small hatchback can indeed be very tricky, but I can manage it (I even think it is easier to load it in a small hatchback anyway, but that is just my point of view). Once the OTA is in, I load the mount in the boot – there is no problem with the estate car, but hatchback struggles, and I have to put it in horizontally - it is like solving the Hedgehog in the Cage puzzle. Operating it For some, the mere dobsonian mount the scope sits on can be a limiting factor, but I think that the very essence of the mount makes the scope amazingly easy to use. Of course that being only Alt-Az type mount operated only manually, you are limited to visual observations only, or occasionally, some webcam planetary astrophotography (but even that is hard enough with high magnifications). However, I as yet have no tendencies to step into the astrophotography area (because I don’t want to bankrupt myself), so for me, the combination of large scope on a dobsonian mount is ideal. You can set up the telescope, despite its size, in less than 3 minutes I’ve checked), even when you are on your own. Of course you stretch your back a bit, but at least it’s quick and very simple. From then on, it is just simple point-and-shoot principle, which I think is fabulous. All you need is to get accustomed to the whole flipped image idea, and anyone can enjoy himself. I once invited a friend over for some observing, who has never seen a telescope of any sort up close - he was able to observe Jupiter and follow it on his own in 10 minutes or so. This just proves it large scope/dobsonian mount is a really foolproof concept, even though it’s purely for visual use. Observing with it As you might have guess, the scope’s primary area of use is DSOs, and I have to confirm that it performs really well. I can finally dive into observing dim and small galaxies and galaxy clusters, and I can finally see some famous objects like the Stephan’s Quintet or the Veil Nebula. As you might expect, objects like Orion nebula look fantastic, and I can even see some nebulosity around the Seven Sisters in Pleiades. The dust bands of the Andromeda Galaxy pop out miraculously, and I am able to resolve individual stars in every globular cluster I have tried so far. Furthermore, the bright image enhances the colour experience, which means that when for example observing open star clusters, their different colours become apparent. Sometimes, I just try and sweep the sky randomly, and there are blobs and fuzzy patches appearing in the eyepiece all the time. The sky never looked so full to me! Planetary nebulae and larger galaxies finally show some internal structures, and with the image being so bright, observing planets with high magnifications delivers really good contrast. There is no point in going into details, but a list of some of my observing reports is below: http://stargazerslounge.com/topic/150839-yet-another-unexpected-session/ http://stargazerslounge.com/topic/150457-unexpected-session/ http://stargazerslounge.com/topic/150127-surrounded-by-forrest-19th-may-2012/ http://stargazerslounge.com/topic/139441-at-last-a-full-on-session-with-my-12/ Upsides Good on DSOs Great on DSOs Again great on DSOs Dobsonian mount is easy to use Great value for money Quick and easy to set up Good Crayford focuser Decent stock finder scope (8x50) Bracket for 80x80 fan Mostly comfortable viewing positions Downsides Big and heavy Big Heavy Hard to transport, takes up a lot of room Occasionally squeaking Manual movements only Alt-az only Visual only Hard-to-reach EP shelf Secondary mirror can dew up Dust cover keeps falling off of the OTA
  9. For sale is my beautiful 10" custom Dobsonian that featured in the Sky at Night Magazine How To Build a Dobsonian Telescope This unusual instrument can be used as a Dobsonian or attached to a suitable mount using its standard tube rings and dovetail bar. The telescope is in fantastic condition with an immaculate mirror - There are three tiny scratches on the tube (NOT the optics!!) as pictured below. The optical tube is fully flocked inside to increase contrast and the standard focuser (included in the sale if you want it) has been replaced with a beautiful mint condition Baader SteelTrack Crayford focuser. A matching 9 x 50 finderscope is included and this has a 90 degree adaptor that can be used (optionally). The well built Dobsonian mount includes an altazimuth scale and lubber line. The rotating table has a bubble level and the base has adjustable height feet for easy set-up on any type of ground. The original box that the telescope came in is included. Collection only, from West Sussex **SOLD PENDING COMPLETION** Whole System Dobsonian Base Altazimuth Scale Finderscope Baader SteelTrack Focuser Tiny Scratches
  10. Skywatcher Skyliner 150P Dobsonian Perfect first scope - simple to setup and use. Used Skywatcher Skyliner 150P Newtonian telescope on a Dobsonian base. Excellent condition. Comes complete with fnderscope, boxed 2x Barlow, Super 10mm and 25mm eyepieces plus a Meade 9.7mm Plossl eyepiece. £150. Inspection welcome. Collection only from Rushden, Northamptonshire.
  11. Hello all! I just installed this Lacerta 1:10 Micro Transmission focuser on my 8” Skywatcher Dobsonian. It is a direct replacement for the stock focuser and works extremely well. I was surprised at how easy it was to install! Ordered it from 365Astronomy and got fast shipping.
  12. I wouldn't want to miss observing the Sun in a full-size 300mm filter, the detail compared to smaller instruments is such a joy to see. I do have an off-axis mask for my 300mm dob but not all the time. If daytime seeing is too bad for such a large scope, I'll switch to a smaller one, but the extra resolution and ease of spotting micro-detail thanks to the brightness is something I can't do without. A sheet of 500mm wide Baader fillm allowed me to craft this. I had enough left to cut several smaller filters. To protect it I made a storage box from cardboard of obvious origin. The box had to be custom-made to save space in my dwelling, and it also hosts a bahtinov mask for nighttime. At f/5 fine focus is not too hard with the smooth single-speed focuser, but in order to enjoy moments of clarity immediately at high power, I pre-focus with the bahtinov, which sees through turbulence, what a nice invention, and simply wait for calmer air. No need to rush to fine focus and waste precious moments. This mask needs to be copied in some sort of plastic, the cardboard trial proved the number and width of the slits are fine. The rear of the filter shows the four clips mating the four button screw heads outside the tube. And this lateral view shows the sandwiching. A rigid backing plus two layers of lightweight neoprene foam cut from a cheap mat in tiger-stripe deco, its poor taste matching its 7€ price. The bottom sheet used to be a shower booth panel, my neighbor had in its garage. Hey, do you need that? No? Okay, thanks! The Baader film is held between the neoprene sheets by staples and many strips of tape. The neoprene is held to the shower booth sheet by little collars, and its edges are sewn together for a finished look. Oversize 10mm stitches didn't take too long to do, and the foam layers can be separated for replacing the film, something glue would prevent. Holes in the neoprene allow to check that the clips' bolts are always tight. Close-up of a clip. They are made of a material whose name I forgot, I only remember it is made in the UK (thanks, guys!). This is a PVC foam that's much easier to cut, drill and sand than full-density PVC, and it's much lighter (thanks, air bubbles!), which is essential for an item that's at the front of a scope where leverage is maximal. My GSO dob has four of these screw heads, one for each spider vane. They proved very convenient for attaching the filter. The black knob is an add-on to move the scope without having to grab the large tube with both hands. Pretty obvious what we're seeing here. Note the clip is flush with the tube, and pressed hard against the scope's metal rim for a very secure and tight fit. Only four clips but eight attachment points, really. Building this with tight tolerances was more lengthy but more reassuring. It is impossible to disengage a clip by accident because tolerances are too narrow, and the shower booth plastic tough spring action doesn't allow it. But should it happen three clips would hold the filter safely. All three layers of frame material are flexible, so, to remove the filter from the tube you just bend it at a corner while you lift the clip, and the clip disengages. I already rebalanced the dob by pulling the 7-kilo mirror to the rear thanks to shorter and tougher cell springs but I'm working on a sliding counterweight made of pliable steel ribbon. Adhesive felt pads protect the paint. Thanks to the large hole the 300mm filter is not too heavy (and it's used without the finder) but the off-axis mask has only a 115mm hole, so it's heavier and may require this. While I study the combinations of heavy or lightweight eyepieces, finder/no finder, mask, filter, I can change the experimental counterweight by cutting off or adding pieces of steel ribbon. Little mounting nuts and bolts through the many holes, there's always one at the right place. Ever hated to feel the Sun while loving to watch it? If you have no sunshield you did. Heat is a discomfort on the head, and light kills off contrast. So I cut a plastic folder in this weird pattern to allow sliding it between the shower booth plastic and the neoprene mat. When it's stuck there it makes quite a large area of shadow, that's such a relief. But that's also only a prototype that wants to be made again with a better material. Has to be opaque, quite thin, very lightweight, but rigid enough. I'll stumble upon the right material sooner or later.
  13. Hi all, I want to share with you my so far best image of Saturn, taken using: 305/1500 goto dob Skywatcher QHY-5 mono IR-UV block filter Baader barlow 2.25 Registax, stack of 40 images, postprocessing
  14. Hi guys just been looking at this Dobsonian over on Facebook, the guy seems genuine and honest however would just like to know your guys input and what would you do, you see i only have this one chance for a very very long time to get a Decent Telescope, ideally i would like to do Planetary and DSO imaging, basically the guy has said it is a 12 inch that has been cast to 16 and that it came from the number 2 at the Grenich observatory. The reason he's selling is because he lost a leg and can no longer pursue the hobby no more with it being a flex tube Dobsonian, it comes with a telrad, 5 filter holder, hand cut lens's, laser set up, computer guided, compass, he is the 2nd owner from new, he said it will need a clean as it has been stood for 6 months, his Facebook link is below, Deep Space Telescope Facebook He's asking about £1.000 for it or a sensible offer but not stupid offers, I've posted the link to it so you guys can look and see what it is about, my question is should i get it or i was going to actually post a thread failing this offer from Facebook as i was looking at some of these scopes over on FLO, our lass has purchased me lens's from there so i know i can trust FLO 100% the scopes from FLO i was interested in are below as follows : Dobsonians Skywatcher Skyliner 300P FlexTube GOTO £1,399 Skywatcher Skyliner 250PX FlexTube GOTO £969 Skywatcher Skyliner 200P FlexTube GOTO £775 Reflectors Skywatcher Explorer 200P-DS HEQ5 PRO £1,089 Skywatcher Explorer 300P-DS NEQ6 PRO £1,678 I really like the look of the Skywatcher Explorer 300P-DS NEQ6 PRO or the Skywatcher Skyliner 300P FlexTube GOTO, Both are expensive and like i said i am only going to get this one chance to buy from FLO really any scope for a long time that's why I'm asking for help as i am in a real dilemma as to what to do, I'm also all for saving a bit if i can, but my sensible side also says with FLO you can trust them 100% and also get a warranty Any help would be really appreciated or even any advise on what scope you would go for if you was buying say with a budget of around about £1.600. Cheers Guys and Gals Mark.
  15. Friday night I used my Skywatcher Skyliner 200p dobsonian for the first time. The seeing wasn’t great , some high clouds. To give an idea of conditions I could just make out the “head” of Delphinius with naked eye. I had set up the Skyliner ( see photo) on some small paving stones although I didn’t try to level it. Carrying the scope out to the garden in two pieces was simple , I have added a couple of luggage straps to help. Moving the scope as an assembly can be done using the two handles to lift the assembly and I managed, during the session ,to move to another area of the lawn to view another section of sky. I have since experimented with a sack trolley which makes moving the full assembly a cinch and I will use this when I go to our local dark sky location I have added a Right Angle Viewfinder and a Telrad to the Scope and using a 30mm EP I firstly made sure that they were all aligned, by choosing a bright star in the centre of the EP and tweaking the two finders to get their agreement. I could see the “box” of Hercules and I have previously seen M13 and M92 with the 130p so I thought that this would be a nice comparison for the 200p. The movement of the scope was smooth in Altitude and in Azimuth. I have added a single piece of milk bottle washer to the centre bolt and this has freed up the rotation. From my experience with the 130p I know where M13 and M92 are . It seems obvious now but it does help that I know what I am looking for and it’s the same viewfinder as on the 130p so I am looking for something with a degree of faintness that is easy to miss. I aimed the scope with the Telrad judging against the top right hand start of Hercules, then located the fuzz of M13 in the viewfinder and then centralised in the 30mm EP. The movement of the 200p was smooth and I was able to locate and centralise M13 very quickly Then I swapped the 30mm for a 12mm Plossl and this is where the dobsonian became a little more difficult, the 200p has a longer focal length than the 130p and more magnification and narrower field of view therefore any twitch can send the object out of the view and sometimes its hard to find it again. I found that I can control it better in Altitude if I” embrace the dobs’”. I am sitting next to the tube eye at the Eye piece if I need small adjustment in Alt I lay my arm along the length of the tube and allow my arm to get heavier. Not a push more a relax. Azimuth nudges at high magnification are more difficult to get with precision. I expect practice will improve matters. M13 was lovely, more detail , bigger ,more stars resolved less fuzzy than the 130p Finding M92 was a bit more difficult, I used the Telrad to guess approximate location and then zig zagged with the viewfinder .The viewfinder has about 5 degrees of field of view so I reckoned a submarine depth charge pattern sweeping a line of 5 degrees to the left then dropping down to the edge of the viewfinder and then a sweep to the right.. it worked and there was M92. Again bigger , brighter and more stars resolved I spent the next hour enjoying the views easily sweeping the scope around the sky, so many stars in such poor seeing conditions ,I am looking forward to darker skies. So in summary I am very happy with the Skywatcher Skyliner 200p Dobsonian. I was up and running in 5 minutes, the EP height is perfect for viewing when seated ,there are more stars on show and greater magnification available. I am going to sort out some fine control for viewing under high magnification but here I am nit picking, it’s a great scope. As a little postscript; As mentioned I have been using the Skywatcher Heritage 130p, also a Dobsonian, for a while, and the experience in using the smaller scope has been very useful as a grounding for this bigger tube. SOme basics that are easy to take for granted ,for example I have some knowledge of the types of eyepieces to use when tracking down a target, some idea of the major constellations, use of sky maps, stellarium and planisphere , some understanding of what to expect when looking for fuzzies etc. I would really recommend that someone new to the hobby ,experiment with the lower cost options it certainly pays dividends when using bigger kit. I wont however be getting rid of the 130p, its portability, great optics and wide field of view gives it a place in my shed.
  16. Dear all, I'd be grateful for some advice please. I currently have an Orion Starmax 90mm mak-cas on a mini dob base, I have a home built, very sturdy, tripod (along the lines of the great design by Dave Fuller) and combined with a 9x50 RA spotting scope and a red-dot finder I find it a very useable set up that performs really well on planets, the moon and brighter deep sky objects. But, whilst I love the scope (I find the optics and portability really good for the price) it's a poor performer on fainter deep sky objects, as would be expected from such a slow (f13.8!) scope. I've recently discovered a real interest in tracking down DSOs, an so would like to invest in a scope that lets me do this a bit better. But- and here's the catch- I want to strike a good balance between light gathering and portability- for me this rules out very anything over 150mm. And, I am only in the market for something on a Dob mount. So, I think I've narrowed my choice down to two contenders, both Dob reflectors, which seem to offer good value for money albeit in different sized packages: Sky watcher flexi tube 130/650 f5: https://www.firstlightoptics.com/dobsonians/skywatcher-heritage-130p-flextube.html Sky watcher 150/1200 f7.8: https://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-150p-dobsonian.html Of these, the Sky watcher 130 appeals most because it gives good aperture in a compact set up and at f5 is a good contrast to my Mak. Whilst I imagine the 150mm will give better all round performance, I am put off by the bulk. To help me make a decision, I’d be grateful for views on: - How much better 130mm collapsible tube is likely to be on DSOs than my 90mm Mak. Will it be notably better, or only marginal? - Is the shorter focal length- and reduced mag without barlows- an issue for DSOs or is the larger aperture the main priority? - How would the 150mm perform in comparison- would there be a notable gain over the 130mm? - Does anyone have experience lugging the 150mm dob around? Any thoughts on these- or alternatives- really welcome. Am I even on the right lines thinking these woudl be better for DSOs than my Mak? I'm looking for max bang for my buck here as my max budget is £200 (so I've largely ruled out the table top Orion 150/750 for example). Many thanks in advance, and sorry for such a long post! S
  17. Hi, Does anyone have any experience converting a Skyliner 200p dobsonian (Non Go To) into a Go To telescope? Can this be done? Any help is appreciated. L
  18. Hello there probably a stupid question with an obvious answer but I've been lurking around this forum for weeks and can't find an answer sorry! Now I'll pre-empt this by saying I'm a total mathematical failure and that is probably the crux of the problem but..... I want to build a small dobsonian for the kids as my skyprodigy 70 just isn't cutting the mustard. Now I think I understand the basics of focal lengths and the such - but as far as secondary mirror location goes (and I've checked NEWT etc and I'm still not completely clear!), am I right in thinking that if a primary mirror has a focal length of, say, 800mm then the secondary mirror isn't actually placed 800mm further up the tube, but that 800mm distance includes the light bouncing off the secondary mirror and up into the focussing hole? All the focussing hole stuff confuses me too tbh; where exactly is that 800mm point supposed to be in relation to the eyepiece? I.e. Just below it, or above it, or at the bottom of the lens? I don't get that because I thought to focus the eyepiece you moved the eyepiece up and down anyway? Why is focussed height so important? Is it a product of the internal diameter of the tube? sorry, I've probably given myself as a total fool. I've read stellafane and a few others about 6 times and I don't get it so that probably says more about my level of intelligence than the quality of their instructions! Many thanks!
  19. I picked up my new (and first ever) dob from Nottingham yesterday. Its a 20" f3.6 Lukehurst dobsonian. It has a 1/10 wave mirror. David Lukehurst gave a quick demo of the scopes features and answered my questions on collimation. Then it was time to dismantle and put all the pieces into my car. I had taken some duvets and pilllows to allow me to get everything packed in and there wasn't much room to spare... Everything was unloaded into my garage just before dark. Today I have been making up some wiring to connect the various "enhancements" that will increase my use of the scope. David had fitted the powered ground board, 10K encoders and Nexus controller plus UTA dew controller unit (he cleverly wired the dew controlled up through one of the hollow trusses which is a neat solution) & secondary heater. He has added a few pass through holes in the corners that made it easier to get the cables out to the mirror box to connect up the fan & UTA dew system. Once that was complete, I got my neighbour to help me carry the mirror box from the garage down to my shed (obsy). Assembly was a breeze as David numbers each side and each of the trusses so you get them on the correct side (easy). I added the shroud then attempted collimation using the Howie Glatter laser & tublug. The secondary was almost spot on and the primary took a half turn before the triangle shaped centre spot appeared in the tublug display. I gave the Nexus a test with a false alignment on the sun and practised some push pull to find the imaginary mercury and mars. All seemed to be working fine. Just had time to fit my astro systems scope coat and see how much spare material there was as the coat is for an f5 longer scope. Anyway, too much cover seems to make the job of putting it on much easier Now, I just need a clear spell to get out and align the finder then we should be away! Alan
  20. A lovely, easily transportable, telescope with smooth motions that keeps collimation well. About 18 months old and in very good condition and excellent working order. Built for me by David Lukehurst with a Zambuto mirror I ordered direct from the U.S. 2 speed Moonlite focuser. Fan with Tracer Lithium ion battery. Antares secondary mirror. Baader Sky Surfer V red dot finder. Skywatcher 50mm correct image finder. Baader Click-Lock extension tube. Cats-eye collimator. Zambuto certificate of performance guarantee and authentication. Zambuto serial no - 4-16-2014 ZOC14.5-034 FL=72.6" £2,500 Any questions...please ask. Buyer will have to arrange collection from Kington, Herefordshire. I expect you would want to see it before buying anyway!
  21. Hi, I'm starting to save money for my new setup (it will take a while, but hopefully this autumn should do), and I'm probably going to buy a dobsonian telescope when I'll move in the UK. I was aiming at 12", I could use a little more light but the most important feature would probably be portability, as I should also be able to take it with me on the subway. Not many 12" dobsonian are really that lightweight (Meade and SkyWatcher are bulky, though being truss), and so the two main models I've been looking right now are the Explore Scientific 12", and the equal size Sumerian Optics Alkaid. Now, the main advantage of the ES is the price, I probably would be able to buy it very soon, but I've read many reviews telling that optics are ok, but mechanics are not, particularly the altitude movement. On the contrary, the Alkaid seems really what I'm looking for, weighting the half, and being even cabin-sized, it would mean I could even travel with it (back in Italy, or to the southern skies, which I've always dreamt of). I'm not very sure, though: the price begins being a little bit too high for me (even though my girlfriend would probably help, she's interested in that too), and I didn't see too many reviews about it. I'm particularly interested in the mechanics, and in weight of single components (most companies have a weight limit, so I would probably be forced to travel with the primary mirror only in cabin with me). So, I'm interested in hearing anyone's experience with any of the two above, or maybe about a different option I might not be aware of Thanks Marco
  22. This is the first mod to my newly acquired 250px. The teflon pad bearings on the mount are quite simply atrocious for a scope that costs over £400.00 new. Simple solutions are on hand though. Enter the B-Tech BT540 Television Turntable. These were available on Astroboot for a while and Amazon UK but they are currently out of stock. I am sure other brands of a very similar nature are available. This is a 16" bearing with a 75KG load bearing capacity. 1. Remove the dob mount pivot bolt and remove the teflon pads. 2. Remove the sticker centre from the turntable and push out the 2 part fixing so it comes apart. On checking the innards it is quite well made with steel bearings running in 3 channels. The centre hole is the same diameter as the pivot bolt so no machining is necessary. Put the unit back together, you can apply a little contact adhesive to the outer edge, this will aid assembly later. 3. Cut in half the dob mount centre bush. For ease of assembly I glued each half back into the woodwork with some contact adhesive. 4. Obtain a replacement centre pivot bolt that is 30mm longer than the original. Should anyone need one to try this mod let me have your address and I will pop one in the post to you. I only have 3 so it is on a first come basis. 5. Line everything up and reassemble with the new pivot bolt. Total build time about 20 minutes including waiting for the glue to dry and a 10 minute trip to my local nut and bolt shop. Mount is totally transformed, smooth and stable. No machining required whatsoever ..... simples
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