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Jules Tohpipi

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Everything posted by Jules Tohpipi

  1. Yes, they are all very good points and why I'll not be giving up just yet. I'll give them a go when time allows (tricky) and taking a vvvvery deep breath....
  2. I had a long session with the 200p and 250px alongside each other on Tuesday night. The results will require a long post - to clearly explain the findings with relevant background information - which unfortunately I don't have time to post tonight. Hopefully tomorrow. The top-line conclusion is that I am deeply disappointed with the coma this scope is producing. It is such a significant backwards step compared with my 200p. Frankly speaking, regardless of price, I'd take the 200p over the 250px because the negative points of this faster scope heavily outweigh the positive points. When I write up the full details I'll be choosing and using my words far more carefully because it's still early days with the 250px. I don't underestimate the need to perhaps fettle and familiarise myself better with the bigger scope. Plus I need to give some deeper context to what I was seeing - such that others might be able to better interpret and explain what I was seeing. Right now though, despite my very best collimations efforts in situ, anything more than half way out from centre ain't worth looking at, alas.
  3. For me it is a thumbs down for the Zoom mkIII in the 250px. Previously using one in a 200p, I found the FOV quite narrow at the wide end. More significantly, I found the view to get quite mushy away from the middle which resulted in lots of Dob nudging. My MaxVisions were a revelation in comparison. Wider, clearer views and good to the edge with better ER. Sticking the zoom in my recently acquired 250px exaggerated the problems further. In fact, as wolfpaw is finding, the MVs are less than perfect in the 250px. On a positive note, my WO 6mm is working well in the 250px giving detailed high mag views when the seeing allows.
  4. Yes, will do. There's a very small window of opportunity before the 200p is delivered to its new home. So I'm praying for clear skies. Glad you found the post useful - as I did yours.
  5. I've just come across this thread and wolfpaw's experiences have mirrored my own recently. I'm currently transitioning between scopes. I started with a Skyliner 200p during which time I bought the MaxVision 16mm and 24mm. The 24mm was exceptional; clear to the edge, comfortable, etc. The 16mm was a pig due to very tight ER. Recently bought a 250px FlexTube. Last night I had both scopes out on the patio alongside each other... The 16mm MV looks so much better in the 200p than the 250px. Stars are more pinpoint for longer in the 200p. Even when dead-centre in both scopes, details in Jupiter were clearer in the 200p. Of course, the image was brighter in the 250px, but it was noticeably easier to discern the details in the 200p. As the 250px is new to me, but used, then it similarly got me fearing for the scope's optics (I've carefully collimated it). Swapping to the 24mm MV, the difference is less pronounced. Certainly, stars are pinpoint practically to the edge through the 200p -whereas they are not through the 250px, but I was expecting that. Other than that the views were fairly similar except for brightness. Unfortunately, the seeing was too fizzy here last night to draw any meaningful conclusions when comparing the two scopes using my 6mm. So, I'm somewhat glad to hear that another forum member is struggling with the 16mm MV in the 250px. Because I certainly am. But I need some more clear skies to test the other EPs more thoroughly across a wider range of objects than just Jupiter. But the 200p is going shortly, so I might not get opportunity if it keeps raining.
  6. If you have below-par orientation skills, enough LP, and are time poor, then a manual DOB can be a very frustrating experience. A Telrad certainly helps but didn't help enough for my scenario. In the end I swallowed my pride and bought a Goto DOB. No, it's not a magic wand. However, used in the right way, dial in some PAE off stars in the nearby area, and it will get you there. I've seen a greater variety of objects in one week than the previous 12 months. Conversely....
  7. There was opportunity to try the SW 200p Dob last night with the Parallizer. The overview is that I was able to achieve focus with all EPs when putting the Parallizer directly into the draw tube, but *only* if I did not insert the Parallizer fully. So I think it's a very good result that focus could be achieved in this configuration and the views were excellent. Attempt 1 Inserted Parallizer into draw tube all the way to its collar. At this point the Parallizer provides zero extension because the inside of its collar is chamfered i.e. like a funnel. I could not achieve focus with any of my EPs (6mm - 24mm). Attempt 2 Inserted Parallizer approx 80% of the way in (didn't measure this accurately). Achieved focus with the 16 and 24mm MaxVision EPs. But no focus with the 6mm WO. Attempt 3 Inserted only 10mm of the Parallizer's barrel (this I measured with the calipers). Could easily achieve focus through all EPs 6mm - 24mm. For cross-reference, the supplied SW adapter (2" to 1.25") only has 10mm of barrel below its collar for the screws to clamp onto; even with only 10mm inserted the Parallizer had no slop or movement in the draw tube. Of course, this fitting of the Parallizer need only ever be done once and you then leave it in place. Attempt 4 Inserted the Parallizer approx halfway into the draw tube. Could achieve focus with the 16mm and 24mm MaxVisions. Could not achieve focus with the 6mm. So, I inserted the 6mm not all the way in, but very roughly halfway in, and was then able to achieve focus with ease. Conclusion Were I to be keeping the 200p, then I would definitely be putting the Parallizer directly into the draw tube. It allows you to perfectly collimate the scope and then definitely keeps everything parallel and in collimation across all EPs, whether the Parallizer is inserted partially or fully, and regardless of how many times you've removed/inserted it. My Cheshire confirmed this. It's a very clever and effective design that ensures sharp reliable views for visual, and maintains the focal plane in the correct orientation for AP. Footnote There's only one minor negative thing to note - other than the price - which is the Parallizer's clamping screw can foul on wide EPs. This was the case with my MaxVision 24mm. The issue is that the screw used to clamp the EP goes in at approx 45 degrees, and if you have an EP the size of a grenade then the screwhead will hit the outside case of the EP before it is able to clamp it. Thankfully there is a workaround, which is to simply pull the EP out about 5mm and then clamp it (the design of the Parallizer will still keep it tight and parallel) - but if you're not paying attention there's a danger you will scratch the outer barrel of your EP, if it's a biggy like the MV 24mm.
  8. Completely... and... utterly... gutted... Glad that some got the opportunity though.
  9. For anyone who’s interested, here’s my interpretation of how the Howie Glatter Parallizer works. It’s not an explanation of the whole principle behind the Parallizer, just a part explanation of how it actually keeps things parallel. (My profuse apologies to all concerned if I’ve got any of this wrong). Background I’d read some explanations online, and watched the video on HG’s website, but personally just wasn’t able to understand the descriptions of how it worked and kept things parallel. So, now that I’ve got one, I think I understand. I hope the diagram I’ve created below helps shed some light for thickies like me who didn’t understand the official explanations.. Diagram The diagram shows a cross-section of a 1.25” EP inserted into a Parallizer, which in turn is inserted into a draw tube (or 2” EP holder). Please note the diagram is not to scale and I’ve exaggerated the size differences between the different elements to aid seeing how it all works. EP into Parallizer The first thing to notice is that the Parallizer is not intended to be a perfect cylinder. On first inspection, the inner diameter seems like a circle; however, look under the green EP and you’ll see a white space. That’s because an extra smaller scoop is taken out of the inner barrel of the Parallizer. It means the EP will come to rest not at the bottom of the tube, but slightly raised up on the ‘shoulders’ of the two (machined) intersecting circles. This inner profile extends the full length of the barrel – meaning that the EP is resting on two lines that extend all the way down the Parallizer. The Parallizer then has a single clamping screw from above. This clamping screw is made of brass with a plastic thingy on the end, both of which ensure your EPs won’t get marked (Howie has emphatically asserted this on another forum). The EP is now held parallel inside the Parallizer. Parallizer into draw tube (or EP holder) A similar principle is applied to the outside surface of the Parallizer barrel. Note how some extra cutting out is performed on the outside surface (at the top in the diagram). It means that the outside of the Parallizer will contact at two points to the draw tube. I say points, but it’s actually contacting along two lines all the way down the outside of the barrel. All that remains is to clamp with a *single* screw from the draw tube. The supplied little instruction note states to use only one of the two screws on the draw tube (or 2” EP holder) and to orientate the Parallizer such that the draw-tube screw is opposite the Parallizer screw. Looking at the diagram it’s obvious to see why this instruction is given i.e. it ensures pressure comes from the right direction in order to keep the “shoulders” of the Parallizer pressed against the draw tube. It then sits inside the draw tube parallel with the inserted EP. Summary So I hope that helps explain – if it was needed – how the Parallizer works. After my experiments with the Cheshire, it certainly seems to be achieving its goals. I think £40 is a little steep for what you get, but then it is a beautifully made speciality item, built in small quantities, and FLO need to make their money too. As it does its job very well, then I’m not displeased.
  10. Some interesting things I thought I’d share from my recent experiences... (Albeit sorry for the long posts, if anyone is still reading). Given how the Howie Glatter Parallizer is intended to work, I was worried that its effects would be spoiled by the need to insert the 2” EP holder first. Totally by accident, I discovered the answer to that question. Well, partially... there’s a story. As mentioned earlier, I collimated the scope at the weekend with the 2” EP holder, Parallizer and Cheshire in place. Scope collimated, I then removed everything. Immediately, I put everything back into place only to discover this - the circle marked on the primary mirror (doughnut I think it’s called) had moved way off to the right! It wasn’t even touching the solid black circle in the Cheshire, let alone overlaid or overlapping. ‘Well, that was an complete waste of time and money!!’ were my immediate thoughts. So, what was the problem? I had not inserted the 2” EP holder squarely. You see, I’d always assumed that the act of tightening the screws would guarantee the EP holder went in square. Wrong. Totally wrong. Turns out I had only part of the EP holder’s collar touching the draw tube - some of the collar had a tiny gap to the draw tube - which meant the 2” EP holder was inserted at a very slight angle, and clamping the EP holder into place maintained that angle – not straightened it out. The outcome being I was staring down the Cheshire with the primary doughnut significantly off target. The solution: I re-inserted the 2” EP holder making sure that the entire circumference of its collar was pressing against the draw tube while tightening the screws. Then, with Parallizer inserted also, and Cheshire into Parallizer, the doughnut was always in the exact right place. By implication, it means my EPs would be as well. This accidental discovery has really highlighted to me just how important it is to get everything *parallel* (not just centred). Otherwise your best efforts at collimating will be compromised. As a follow-up crosscheck, I then removed the Parallizer and inserted my regular 2” to 1.25” adapter. This adapter has to be inserted into the 2” EP holder meaning it’s effectively a two-piece adapter (unlike the one-piece 2-1.25” adapter supplied with the 200p). Anyhow, added the adapter, inserted the Cheshire, and the primary doughnut was a mile off again!! Clearly the 1.25” adapter was not in square but, because of its design, I couldn’t find any easily repeatable way of inserting it at a consistent angle. The design of this adapter always felt and looked a bit rubbish anyway. So, for my particular case with the 250px, the Parallizer appears to be providing two benefits. Firstly, its design ensures that it goes parallel into the 2” EP holder. Secondly, it ensures the 1.25” EPs go into the Parallizer in... parallel. The viewing was terrible last night, but nonetheless my gut reaction is that I’m going to get my sharpest ever views some time soon because alignment errors in the adapters and EPs are being removed. The question remains though: is the 2” EP holder going into the draw tube parallel? Well, I don’t know the answer to that question. But at least I can collimate everything to that current baseline safe in the knowledge I can consistently recreate it. If I had some extra collimating kit e.g. laser that could fit into different-sized tubes, then I could determine how square the EP holder is. It’s early days but I might be a convert to Howie’s declaration that “centering is nice, but parallelism is golden”
  11. A quick update. Had the 250px DOB out for a brief observing session tonight. Was able to achieve focus with all my EPs. That's the 6mm WO, 16 & 24mm MaxVisions. Just to recall the set-up: this scope has the SW dual-speed focuser fitted. I inserted the 2" EP holder into the draw tube, then the Parallizer (all the way in to the collar), and then my 1.25" EPs. (The Parallizer won't fit direct into the draw tube on this focuser). Even with the dreadful seeing tonight, the results were very promising. I had carefully collimated the scope at the weekend with the Parallizer in place. Learnt a few things about it in the process, which I'll save for a later report. Once collimated, I removed and then reinserted the 2" EP holder, Parallizer and Cheshire multiple times over and every time the view down the Cheshire was identical. So that's a 10/10 for repeatability and consistency. The only thing I had to be careful about was ensuring the entire circumference of the collar of the 2" EP holder was butted up against the draw tube before securing its screws. Then I got consistent views down the Cheshire every time. Regarding the 200p Dob, unfortunately I didn't get chance to try that out with the Parallizer tonight. The scope is in an upstairs bedroom and I didn't want to risk waking our little one (technically, I didn't want to risk my wife murdering me for waking our little one). The Parallizer will go straight into the draw tube on this, and although I'll be selling scope, I'm still curious to see if it can achieve focus without extension tubes.
  12. Possibly, but then the EPs might achieve focus pushed all the way in, or pushed anywhere in so long as in the range from 10%-70%. Just hoping for a break in the clouds to have a play.
  13. Well, it was a beautiful day here. That is until 5pm when I watched the clouds roll in. So I've been having a play with the Parallizer indoors instead. Now, I temporarily have two telescopes in the house - for which the results have been rather different. For reference, the diameter of the Parallizer is a hair's breadth under 2" according to my Vernier Caliper. Skywatcher Skyliner 250px FlexTube Dob This particular telescope has the Skywatcher Dual-Speed Crayford Focuser fitted (non low-profile version). The Parallizer will not fit in the draw tube because the diameter of the Parallizer is too big. Therefore, the Parallizer must be fitted to the 2" EP holder supplied with the telescope. Then I can insert my 1.25" EPs into the Parallizer to look at the underside of all the clouds. Skywatcher Skyliner 200p Dob This telescope is around one year old and unmodded. It has the single-speed focuser. The Parallizer fits perfectly directly into the draw tube. Now, this next section is a bit difficult to describe without diagrams but I'll give it a go. It's difficult to describe because the outside dimensions of the adapters don't quite tell the whole story. Anyhow, I'll stick to the overview for now. The supplied Skywatcher 2" to 1.25" adapter (which is intended to be fit directly to the draw tube) provides around 45mm of extension (46.5 mm according to my measurement on the calipers). If you insert the Parallizer directly to the draw tube then it provides no extension. (The Parallizer has a 9 mm tall knurled collar; however, it is chamfered on the inside so provides no extension). But the good news is that all is not necessarily lost if you need some extension to achieve focus. The length of the barrel on the Parallizer (as measured from below its collar) is around 35mm. So let's not insert the barrel all the way into the draw tube. Let's insert it only, say,10mm in to allow for clamping inside the draw tube (as does the SW adapter). Great, so now at least we have 25mm of extension compared to 45mm of the Skywatcher adapter. Still with me? Where am I going with this? Well, if I don't insert my EPs all the way in to their collars, then I was able to get effectively 45mm of extension using the Parallizer (I just clamped the EPs at the end of the barrel and did not rely on dropping the EPs all the way in until they hit their collars). Therefore, on the 200p, it might well be possible to achieve focus - even if inserting the Parallizer directly into the draw tube. Will have to wait for clear skies to find out one way or the other. Build quality I'll save a fuller review for later, but build quality of the Parallizer is every bit as good as I was lead to believe. Now I have it in my hands and can look at the design, it's apparent how it works and achieves its goals. It's a very simple and clever idea. That side of things *definitely* needs a diagram! Simple if you see it but difficult to explain in words. Will update further when opportunity arise to point the scopes at the sky...
  14. Ha, ha! That's exactly what I thought! But I'm finding it rolls off the tongue in quite a cool kind of way now. Lol. And 'Parallizer' has a clever double-meaning. Ooo, and it sounds like something from Hitchhiker's Guide to the Galaxy. He seems to be an interesting guy and regularly pops up on forums to advise and clarify things about his products. So, count me in for for giving some of his stuff a try! Yes, this is one of several things I'm still in the dark about. If I'm understanding the principle correctly, then it should work better if inserted directly into the draw tube - rather than into the SW 2" EP adapter. Unfortunately, I forgot to ask FLO this in my email. But I will try it both ways and report back when it arrives. Breaking news.... it has just arrived while typing this! Only ordered late yesterday morning, and here it is less than 24 hours later -- on a Saturday morning. Yet more brilliant service from FLO.
  15. Thanks for the heads up. Earlier today I ordered a Howie Glatter Parallizer from FLO who seem confident that I won't encounter any focusing problems or need extension tubes on the 250px. I mainly ordered it because of the outstanding praise from users on the other side of the pond. The Parallelizer should arrive early next week, so I'll report back with the results for the benefit of the knowledge pool.
  16. Thanks for all the replies. Definitely seems like a good bet then. James: no the Skywatcher adapter does not sit flush; it's a one-piece item with an integral extension tube.
  17. I’ve been thinking of buying a self-centring adapter for my telescope, but after a lot of reading I’m rather confused. I wonder if anyone can advise for my particular circumstances please? Gear Skywatcher 10” FlexTube Dob used for visual onlyEPs are all 1.25” and it’s highly likely to stay that wayDob has the dual-speed Skywatcher Crayford focuserMy main aim is to achieve a set-up that allows for accurate, consistent, and repeatable collimation for better visual IQ across my EPs. The other benefits of an SCA would be a bonus but non-essential. Now, if I’m understanding correctly then: I require a 2” to 1.25” SCA?The SCA would be inserted into my 2” Skywatcher EP holder?I then insert the EP into the SCA and tighten? My concerns are: Is this a worthwhile upgrade for visual-only observing?Is the Skywatcher dual-speed Crayford of good enough quality to see the benefits of the SCA?Do things go out of alignment anyway, from session to session, because the Skywatcher 2” EP holder has to be secured with thumbscrews?Open to suggestions on a suitable SCA, but I like the look and concept of the Howie Glatter Parallizer (and indeed his collimators but would be using a Cheshire in the shorter-term). Any opinions gratefully received...
  18. Oh, and just to add, avoid the 16mm Maxvision because it has terrible eye relief.
  19. When I had the Skyliner 200p, then I treated myself to these: http://www.firstlightoptics.com/william-optics-eyepieces/william-optics-spl-eyepiece.html I got the 6mm for special occassions (good seeing) when I wanted the highest magnification to see planets/moon as big and as detailed as possible. As I look at moon/planets frequently, so I could justify something more expensive (without going crazy). The 6mm has great eye relief and is clear to the edge. This means it works well with my glasses (I can see the entire field of view) and I don't have to nudge the telescope along so frequently because the view at the edge is practically as good as the view in the middle. The performance of this EP exceeded all my expectations. http://www.explorescientific.co.uk/en/Eyepieces/Maxvision-68-Okular-24mm.html I treated myself to this for widefield views. You might have read elsewhere on the forum that this is a re-make of a much more expensive EP that sold for several times more money. So, it has become very popular indeed as it's a superb bargain. Again, great eye relief for my spectacled eyes and very clear to the edge. Much better than I ever expected and sooo much better than the supplied Skywatcher 25mm EP. I mention the two above because you might be like me i.e. wanting a great widefield EP and a great EP for close-up work (without breaking the bank). Then flesh out the other areas with the BSTs - as and when budget allows.
  20. You might tread in a cow pat.
  21. First time out with the new-to-me SW250px Goto DOB. Still some fettling of it to be done but the results were promising - even in the wobbly air. Pure good luck to see the shadow on Jupiter, so I fired up the 'Jupiter Guide' app to find it was Europa in transit. Result! Then the GRS made an appearance later in the night for good measure. Saw the Trapezium in M42 as clearer than I'd ever seen it before. Enjoyed not having to nudge the DOB every ten secs when at high mags; could just have a long stare instead. Good night out again, at long last. Happy bunny. Sounds like I was not alone!
  22. It was a clear night here so was able to watch the transit. GRP appeared before midnight, too. No clouds but seeing not fantastic either. First decent session with my recently acquired SW250px Goto DOB.
  23. Oh, and if you are jailbroken then get SwipeSelection (no space) ASAP off Cydia. It revolutionises the ease of editing text when entering coordinates, etc. The video on Cydia and YouTube explains it beautifully.
  24. Congratulations on your new arrivals! Looks like some fun times ahead for you, and literally a lot more to see. BTW, my wife is extremely upset with you. As the result of your thread I will be the proud owner of a SW 10" DOB with Goto in the next couple of days. So don't expect the clouds to clear anytime soon.
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