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russ.will

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Everything posted by russ.will

  1. Great little Barlow, but as I have an ES FE, I don't really need it. Excellent condition and it will be posted in a bolt box. £22 posted to mainland UK. PayPal preferred.
  2. Basically, this is a WO badged Stellarview F50M/TS 50 mm angle finder with 90 ° -amiciprisma - 1.25 "-helical extension. It's the one so well reviewed by Astrobaby. The crosshair eyepiece is the TS Optics 20mm cross eyepiece 1.25 "- 70 ° ERFLE - Self-focusing The illuminator is also TS. That's a £235 finder. I'm asking £150 inc shipping to mainland UK. I will consider selling the rings, but they are a monolithic type with a Meade/Bresser/ES foot I imported from the States, for a fair bit of money, as I didn't like the wibbly screw together types. These would be £50 posted, or £40 if bought with the finder.
  3. Mint condition Farpoint 1.25" laser collimator and Cheshire eyepiece kit. Comes with mirror center spot mask and three remaining center spots. £55 posted Paypal only.
  4. Ooh! Interesting and some very positive comments from TV users too. Near 100deg AFOV and 20mm eye relief? Are we seeing a paradigm shift where the pupil starts to push past the master? Let the dust settle and we''l see where this bottoms out. Russell
  5. I'd compare it to my C100 focuser, but I'd have to track down the recycling centre it ended up at! Russell
  6. They may be good, or they may not, but Bresser seem to have come up with a new [Crayford?] focuser across the entire range. I dunno what the Newt focuses were like, but the old frac focusers, whilst able to hold pretty much anything, were a bit agricultural in operation - read patience was required! Single and dual speed variants seem to be available, but I can't tell if it's possible to upgrade from one to t'other, yet. The interesting scope is the "new" 8" F6 Dob. I say new, but the OTA ( bar the focuser) and indeed the tube rings are all as before; read nicely finished with GSO mirrors, so par for the breed. No, it's the fact that at a princely £333, it comes with a relatively compact Dob base (again, compared to the budget breed) that has, wait for it, decent sized Alt bearings. Who'duv thunk? Better still, because these bearings bolt up to standard tube rings ( just add dovetail and off you trot on an EQ mount) faffing about with counterweights is negated. You simply loosen the bolts and slide the the OTA up/down to rebalance. The Alt bearings appear to have the same surface material as my old ES Dob did, so it should work very nicely. The base also breaks down for transport and because it has metal threaded inserts, they won't strip the threads. I don't know how quick it is to do this, but it at least seems you won't end up with bolts spinning in chip board dust. I've no idea what the bundled "LED finder" is, but I assume it's the same item as bundled with the ES Dobs, which is best described as adequate. The reason for this assumption is because it seems to me that the Bresser plugs the gap under the smallest ES 10" truss Dob. Given that there is no existing 10" or larger Bresser OTA to give this treatment to, I think this is a reasonable assumption. All the same, nice to see a new addition at the budget end that offers a sound mechanical difference for it's existence. Russell
  7. Nor mine, but it just seemed to be one of those sensible (and free!) suggestions that can't possibly hurt, if it's practical. Russell
  8. Don't fit Bob's Knobs. They may make collimating easier, but with their little squishy plastic tips, collimation will be required much more often - They're a self fulfilling prophecy. +1 on a focal reducer. I'm pretty sure the Antares 0.6x will work, as it doesn't correct for coma. The Edge HD and Meade ACFs are coma corrected anyway. The massively expensive Celestron item [may] only really have an advantage when imaging in terms of field curvature at the focal plane or some such. PM me because I have a spare Antares you can have for postage to have a look see. Use the scope before looking into Crayfords. From the few SCTs I've used, mirror shift can vary from being a real pain in the butt (moving a subject from one edge of the FoV in a 20mm EP) to barely noticeable as it is with my LX200R. Finally, store it pointing upward. The primary mirror slides on a grease covered tube. You don't want a lump of that falling on your secondary because it got a bit warm one day. Russell Sent from my iPad using Tapatalk HD
  9. But it shouldn't cross thread and Jam. My 1.25" Rev did and TH replaced it under warranty. This one has been flawless. Russell
  10. You see Televue? THAT's how you do a dual 1.25/2" barrel and NO undercut. Russell
  11. What focuser is that and where (if you had to) did you get the adaptor?Russell
  12. I thought it was 120mm clear diameter between the lens spacers? I didn't measure mine, but I'm sure an American said it on an interweb forum, so it must be true.
  13. I don't think you will be disappointed. It shows a hint of colour, but when you point it at something dull, the extra aperture makes itself felt in a way that is far more beneficial. Russell
  14. Having experienced the before/after results of a professional collimation of both a Achro doublet and an Apo triplet, I would not say you are being paranoid. I'd say refractor collimation was mandatory, but I would also include the diagonal as part of that requirement. In either case, that which comes out of the box, may be close at best, but the magic is in the optimisation of the complete system, accounting for simple things like compression rings not quite gripping orthogonally. Russell
  15. That's exactly what it does. Reduces your FL, giving less magnification and wider views.
  16. I thought all of the test results were interesting, albeit there's less results for the ES than for the multiple SWs. The best SW was the best of the lot, with the ES second, but then the worst SW was also the worst of the lot by quite a margin. I suspect if you lined up three of each, the average result for each would be virtually interchangeable. Clearly, one pays one's money and takes one's chances with these cheap Chinese Dobs in terms of optics, but no one seems to be complaining from among the massed ranks of owners under actual night sky conditions. I whined a lot about my SW, but it then delivered superb 300x views of Jupiter on one particular night just before I sold it. The ES delivered similarly impressive views on a couple of nights, was a lot easier to transport, but needed collimating more after each tear down/set-up. the ES had a MUCH nicer focuser, but it was set at a silly angle, etc, etc. I suppose it just comes down to which package you fancy modifying the most, because I couldn't live with either in their out of the box state. Russell
  17. A lot of people say the same thing about any 100deg AFOV EP full stop. I'm obviously not one of them, but it doesn't make them wrong. Russell
  18. I think that was exactly the point I was making. It's horses for courses and let's be honest, with a very few exceptions, we're all messing around with amateur to lower mid market scopes at best, so it looks like an extravagant anomaly. If you have a large AP or ex-Tim Wetherall refractor, you're batting on a different quality of pitch. To diss it, is to say that a track day Lambo is daft when you're happy with the performance of your road-going Focus ST. Sure, great little car and able to scare you on occasion, but if you had the means, you'd be sitting at the pit lane exit, waiting for the lights to go off, with your three point harness strapped up tight and a V12 burbling behind you. I would, anyway. My point is that for some, the stakes are higher and what looks like preposterous solution at our level, is simply another option at that level. Russell
  19. Y'know, if TV had turned this out, you wouldn't be able to beat people off it with a stick.... As a point of note a 41mm Panoptic has a 47mm field stop v the 52.2mm of the ES100 30mm - a 9% increase. I'm using a 40mm SWA with a 46mm(ish) field stop in a telescope with an exit aperture of 38mm - 21% increase. Under a dark sky, the vignetting in my scope with the far larger deficit is not noticeable. Whilst I wouldn't push it as far as the 30mm ES100, I'd suspect that in SCTs of 10" and up, the vignetting would be a non-issue. Balancing, well don't take it on if you're not prepared to, but it's no more than a Denkmeier Binotron 27 with a couple of Delos and a decent 2" diagonal. I suspect when ES produced this, they had in mind the REALLY large Dobs that proliferate in the US. When you look at the cost of the EP, plus a 3" coma corrector, it looks less stratospheric if you deduct the cost of the 2" coma corrector you no longer need and set it against the backdrop of a £10k scope. Russell
  20. Y'know, the LBs have their detractors and fans, but you can't help but think they're one very pretty little scope. Russell
  21. I have the 40mm Maxvision SWA and in my 8" LX200R, it is absolutely lovely. Pin sharp, edge to edge. Theoretically, there should be some vignetting from the 38mm exit aperture of the 8" LX200 serving the 47mm (?) field stop of the SWA, but try as I might, I can't see it at night. It should also be a bit of a balance issue, but the 8" LX200 is massively over-mounted and by deliberately using a heavy dew shield (it's not like the ES100s or binoviewer are light either) to counteract this, I've not run into any issues with the scope becoming tail heavy. Russell
  22. I've held one in my hand and it was nearly twice the size of my fist in every direction and I have a large fist. Mind you, in the world of observatory class EPs (rather than the amateur stuff we faff around with) it barely registers. Russell
  23. But it is an easier mounting proposition on a alt/az mount due to it's shorter length. At a given magnification, it is less wibbly, if not quite so contrasty. Russell
  24. Yeah, you'd think so, but as the whole OTA is behind a Baader ASTF filter that rejects 99.9% (or whatever) light/heat from entering the OTA and the flange it's mounted in provides another 50mm of shadow around it, it's probably the coolest thing in the garden - on several levels! Thinking about it; there's a lot less energy entering the LX200 than there ever was the 80ED, which was pointed, unprotected, directly at The Sun and had a really hot thing mounted at the back. Until you asked that question, I hadn't thought of it that way. There must be some sort of tube currents generated by a hot wedge? Russell
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