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ollypenrice

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Everything posted by ollypenrice

  1. Indeed we did. The Taks (now a pair) have moved into a block built observatory on the other side of the path.
  2. For me too, with my older 10 inch. This one is staying just as it is! Olly
  3. So, some finishing touches. Steve's cable with low profile 90 degree jack: New cladding on the roll off. Note that the pod on the side is now an eyepiece pod rather than a PC pod! And last but not least... Olly
  4. Good idea on slew speeds. I'll do that. I don't have to worry about the noise but wear on the gears is best avoided. Thanks. We found no need to re-synch during our first night out but, yes, it's an option. To everyone's surprise the GoTo was bang on all over the sky. Given a simple two star alignment we found this remarkable. I guess the mount's measurement of its own tilt plays a large part in its success. Pity we can't do GEM polar alignment this way! Olly
  5. Awe, you're most kind Steve. I was expecting it to be a great pleasure to meet you and Jane and, of course, it was. In spades. My robotic client was also delighted that you could fix his autofocus. I guess I had the wrong steam pressure going... I'll post a bit more on the Meade 14 inch once its brass plaque arrives (naming it for Alan and currently in the post). Your cable will need honorable photographic mention as well. And there will also be, thanks to Jane, the floral connection between the Chanconbury Observatory and Les Granges.... I just need to find a competent daytime photographer for all this. Sincere thanks for giving us a great couple of days. Olly and Monique.
  6. The 'adjustable cell' shouldn't be overlooked lightly. If a refractor has a properly designed cell it can be recollimated if necessary. Olly
  7. The collision is worse than it looks in the picture. Olly
  8. A thing of beauty is a joy forever! Warmest thanks, Steve. Olly
  9. Oooh, that has a lower profile than a Westfield Seven! Brilliant, Steve. Most kind. Olly
  10. You may well be right. It's a shame that the alternative socket on the fork tine doesn't work. That would have been a good solution but Steve Richards is coming to my rescue, bless him. Olly
  11. And you shall have my hearitest thanks! Olly
  12. It is three contacts, sorry. It's 3.5mm in diameter and 14mm deep. If you could it would be fantastic, Steve, but only if you've time. Olly
  13. I think there are just two Steve. Olly
  14. I strongly suspect it's original but, as you say, it should be possible to find an alternative plug. Olly
  15. I've never been unreservedly keen on SCTs. They give large aperture from small volume, make great solar system imaging scopes, are very comfortable to use visually in Alt Az mode and have tended to give me eyepiece views which had the information but not, for me, the engaging thrill of being out in space. Somehow the stars weren't really pinpoint tiny and the backgrounds weren't as dark as I'd have liked. It's hard to explain but this opinion grew while I owned first an 8 inch and then a 10 inch Meade. (It wasn't down to collimation, which is easy to get right on an SCT.) I've been very impressed by the only C11 I've tried, though. Anyway, rightly or wrongly it was was these expectations that I spent my first observng night with the 14 LX200 GPS kindly bequeathed to us by Alan Longstaff. I was in for a very big surprise... GPS and Go To. With the control panel on the south side (not the north as shown in the picture!) you set the tube to horizontal and pointing north, then ask the mount to align automatically. It performs an assortment of gyrations, twists and tilts to orientate itself before heading off to a star named in the handset. The first was Arcturus, which it missed by about 15 degrees. You centre this in the EP and confirm, whereupon it coffee-grinds its way over to a second star, Dubhe this time. It was in the EP. Encouraging. And that's it, you are now supposedly aligned. There is no need to set time, date or location since all come from the GPS. Jupiter was up so we performed a GoTo and the planet was just out of the EP (a 26mm TeleVue Nagler giving 135x.) Not bad but not ideal for a complete beginner had the target been an obscure DSO. 'Going To' Saturn produced the same 'near but not quite' result. However, when we asked it to go to M22 it ground more coffee and, bang, there it was smack in the middle of the EP. And this remarkable precision on DSOs continued throughout the night and all over the sky. All present were mightily impressed. I suppose there is some minor glitch in the planetary ephemeris but it won't be a priority to sort it out since it's easy to find and centre the planets anyway. The views. I was knocked out. Tiny, tiny stars against the darkest of backgrounds. (We were SQM21.6 last night.) The Nagler allows, nay requires, you to move your head to find the field stop. The superb stellar quality was maintained edge to edge. The views were not just informative, they were beautiful. A favourite was M24, the Sagittarius Star Cloud. This was too big for the FOV, naturally, but cruising within it we found clusters within clusters and, notably, some lovely powdery patches of minute stars which I don't recall seeing before. This is the kind of view I love. M51 wasn't perfectly placed but showed spiral structure, 'the bridge of light' and a satisfying scale and brightness at 135x. In fact we just left the 26 Nagler in all night, after quitting the planets. M27 was very dumb-bell shaped, the central star was just visble in averted vision for me and, again, the scale and brightness were very rewarding. There was nothing of the 'fuzzy blob' about it! The FOV is limiting with a 3.5 metre focal length but the sky is not short of targets at this magnification if you have the aperture to support it. This and that. Because we couldn't get the electronic focuser to work we were obliged to use the moving mirror focuser. It was OK, but has the well known backlash. Best to make your final focus a push of the mirror against gravity. Image shift was very slight and there's a mirror lock available. We have the electronic focuser which seems to be a motorized Crayford, but its cable collides with the fork mount! (I've been seeking advice on this on another thread.) An alternative focusing socket on the fork higher up, and not mentioned in the manual, doesn't work. One way or another we'll sort this out. Grinding coffee. The scope is loud when on the move. We don't have neighbours nearby and Alan was two miles from the next house in Shropshire, but if you observe from an overlooked suburban garden the noise might very easily be an issue. Stability. The tube is held stiffly in altitude but has quite a lot of elasticity in azimuth. This seems to have diminshed since we began running the scope a few nights ago and is not an issue for observing. I wouldn't want to try DS imaging without much more stiffness in the RA drive, but we have no DS imaging plans for this instrument. We want to let it do what it's good at. Conclusion. Because this scope was Alan's and was a gift from him I really wanted to like it. Happily, I do like it. In fact love it and can't wait to get out there with a long shopping list of targets. The views are just what I want telescope views to be and the excellent GoTo makes for an enjoyable evening's observing. A beginner can sit down at the scope with a list of objects and set off with no need of help from anyone else. OK, the FL is long and somewhat restricive but the aperture compensates for that by supporting high magnification. With a Telrad on top (not seen in the picture) a beginner can see where the scope is pointing and pick up a pair of binoculars to take a different kind of look at the same part of the sky. That scruffy roll off in the background has now been re-clad in respectable marine ply and is awaiting a brass plaque identifying the scope simply as The Alan Longstaff Telescope. Olly PS The Wild Duck Cluster was Alan's favourite and it really was lovely in his scope. Its improbably geometric shape was shown to advantage by the smallness and brightness of its stars. I always think it looks like a distant space station. Wonderful. Roll on the coming of night.
  16. It does show every sign of being original. The other end goes directly into the focuser unit and doesn't seem to have been touched. The presence of the extra focuser socket on the tines, and not mentioned in the manual, suggests that they had a problem. Not to worry, it can be fixed one way or another. The error is reprehensible but I must say that, after using the scope last night, I am thrilled to bits with it. I've had 8 and 10 inch Meade SCTs before. The 8 inch was 'okay,' the 10 better, but while the 10 pulled in the light you'd expect it to and the images were full of information, they lacked that emotional buzz which comes from tiny, pinpoint stars and a dark background. The 14 inch, however, really did deliver. It was a thrill to use and greatly, very greatly, surpassed my expectation. I'll review it in the appropriate part of the forum. Olly
  17. Many thanks, Davey. Yup, what's changed is that the fork tine has more metal and the clearance is gone. Looks like the silly so-and-so's didn't think it through and added the alternative socket up on the tine as an afterthought. I've just had a look inside at the second socket but there are no obvious loose wires. I'm wondering if you are supposed to configure your choice of socket in some way. At least I can see why there's a problem. Cheers, Olly
  18. I'm setting up a 14 inch LX200 which came with Meade's microfocuser controlled via the handset. It works, but there's a problem. The focuser plugs into the control panel using a right angle plug which seems to be original. Trouble is, as the fork swings round in azimuth it collides with this plug which simply sticks out too far. It's fully inserted, though. I can see no way that the standard plug could ever clear the fork. There is another socket marked 'Focuser' on the inside of one fork tine but, when I use it, the focuser doesn't work. This extra socket gets no mention in the manual. I have to wonder if Meade slipped up when they beefed up the 14 inch fork, as I believe they did, and created this problem. Can anyone advise? Thanks, Olly
  19. By 'actual colour' you mean 'perceived colour,' I guess. If, by 'actual colour' you meant the light sent out by the object, then the huge gaps in the RGGB passbands mean that you would really get vastly more information out of a filter set without gaps. No? I think that, since the OP asked about mono or colour, we should not turn it into DSLR or CCD. That's for another thread. Olly
  20. It is an advantage that your tracking is not perfect when doing fast frame camera imaging. It means that different parts of the target land on different pixels each time, so noise from the chip is averaged out while signal from the target builds up when you stack. Take one bad pixel on your chip. It finds itself in a different part of the image each time so its damage is averaged out to almost nothing. This is possible because the stacking software reads each image and aligns them to one you have chosen as a good one. It is the equivalent of guiding after the video has been shot. Individual fast frames are too short to be affected by blurring due to the mount's errors. But if you want to expose for ten minutes or thirty minutes then you need a guider to keep the mount on target throughout. Olly
  21. I'd agree with this if you didn't have to do so many work arounds to make DSLRs function for astronomy, for which they were not intended. I use Atik cameras and the user-friendly default software called Artemis Capture. It is designed for astronomy. It just plonks everything you need on one screen in front of you and off you go. You can, in luminance, pretty well guarantee that in a 5 second sub (maybe binned 2X2 or 3X3) you'll be able to see you target easily and frame it as you wish. You have a full width half max focus tool. You have cooling to control noise. In short you have the right tool for the job. I think DSLR astrophotography is obscure and confusing... Olly PS While working as a motorcycle instructor I once had a young lad turn up so I gave my usual introduction and then set him off for a gentle potter around the training circuit. He let the clutch in nicely enough but always keeled over shortly afterwards. I was stuck for a solution till it occurred to me to ask if he could ride a bike. He couldn't. Aha! After that I always made a point of asking but this had never come up once in my own instructor training.
  22. I can't see why mono would be significantly harder. You just shoot through a red filter, then a green, then a blue, giving each image a name to identify the colour. Processing goes like this (in AstroArt for me.) Stack the reds, the greens and the blues to make three images called Red, Green and Blue. Go to Images, Align All, set to Translation and Rotation and click once. Go to Colour, Trichromy, and put the red in the red box, the green in the green and the blue in the blue. Check Auto White Balance and click once. You now have an RGB image. At this point you will be in the same place as you would be with an OSC. Both will have gradients which need processing out. I often think that only people who haven't tried mono imaging think that it's difficult! I just don't think it is, though. Olly
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