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NGC 1502

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Everything posted by NGC 1502

  1. Great thread……here’s my thoughts…… When a finite mind (that’s me/us) tries to understand the infinite we cannot. An earlier comment said this is where we bump into theology. As theology is banned on SGL we cannot continue a discussion in that direction therefore I won’t, because I don’t want to be a banned member. Ed.
  2. As long as the movements are very smooth (which I fully expect they will be) I can easily live without slow motions. I once had an Astrotech Voyager alt-az with slow motions. It does depend on the length of the scope but even with a 900mm focal length refractor I found stretching for the slo-mo controls was a pain. I tried longer cables but it was still a pain. It was far easier to hand guide by holding the focuser because that’s always in a convenient place. The other issue was the AT Voyager dovetail clamp was on the end of an arm. I found that a Giro type mount with the weight of the scope closer to the mount head was noticeably more stable, so I think I’d prefer the similarity with the AZ 100 & 75. YMMV of course…. Ed.
  3. I have some BST Starguiders bought new a few months ago. The rubber eyecup just pulls off. To do that it doesn’t need to be screwed up or down, eyecup pulls off at any position. So why did I pull eyecups off new eyepieces with no issues? Dunno…is the honest answer….. Ed.
  4. Some observers use an accessory called a “Monk’s Hood”. Basically it extends beyond the face to help block ambient light. I often use a balaclava helmet that has a floppy face opening that does the same thing. Keeps my head warm at the same time. One issue that can occur in cold damp weather is restricted air flow around the eyepiece can cause it to fog up. But the basic idea of blocking ambient light can be a simple way to make the view more contrasty. Ed.
  5. The previous post does highlight the frustration of dodgy forecasts and I certainly understand that. I arrange visits to one of my local club’s dark sites and it’s myself who’s usually responsible to confirm or cancel the scheduled event. Often it’s a tough call. But when it all comes together it’s great to be together under a good sky and makes up for all the hassle. Observing on my own is far different, it’s then I can relax without the further frustration of all the hi-tech equipment that just gets in the way of enjoying the night sky. I echo 100% previous comments. Ed.
  6. +1 for this. The following morning when the scope will be at inside temp uncap everything as above, no new moisture will form. Allow to thoroughly dry out, cap and safely store.
  7. Good advice already given. I’d like to add the following for observers in the northern hemisphere. In any scope without a drive, if you watch where stars drift OUT of the field of view, that’s WEST. If you nudge the scope towards Polaris, watch where stars ENTER the field of view, that’s NORTH. Ed.
  8. There’s no doubt that a good 4” refractor gives lovely views with stars as tight points of light. But if you want to see globular clusters looking like a ball of stars rather than a fuzzy patch then a larger reflector gets the job done at a fraction of the price. The old “horses for courses” applies. Ed.
  9. Good advice already given. You’ve also mentioned the 24mm Panoptic you already have. It’s a super lightweight well corrected eyepiece. The listed eyerelief is 15mm, same as the Ethos. If you’re ok with 15mm then that could help your decision. Many would be fine with a 24 Pan for low power. However as is often mentioned, TeleVue measure the eyerelief from the glass which is technically correct but doesn’t take into account the fact that the lens elements are not flush with the upper parts of the eyepiece including the rubber eyeguard. That reduces the eyerelief from the technically correct to the more useful available eyerelief. Ed.
  10. As you already have the 12mm and 5mm BSTs if it were me I’d fill the gap with the 8mm BST. The Vixen 8mm is a good eyepiece but I think you’d miss the wider field and good eyerelief of the BSTs. I’m blown away by the price and decent performance of the BSTs.
  11. Excellent Alan, what a privilege Please don’t worry, we won’t ask you to “spill the beans”. But just watch out for bright lights and rubber cosh next time at a dark site Cheers from Ed.
  12. Most of us on SGL know exactly which dealer is being discussed. A while back I had a load of astro kit to sell and considered my options. Having tried to sell individual items previously and found it hard work, the need to hang around waiting for folks to decide, then individually packing and posting, I decided to sell the whole lot to the dealer under discussion. I worked out my price, contacted him, price accepted without haggle, sent one parcel, was paid promptly. I suppose I could have got more money if I’d been prepared to wait and put lots of time and hassle into it. But being busy even though retired I took the best option for me. I’ve also bought items from this dealer. Items were accurately described, any faults disclosed. promptly posted, and the prices whilst being at the top of acceptable, I personally consider a good deal, taking everything into account. However I do accept it’s galling when prices are clearly OTT, however if that’s the case then don’t buy it. Ed.
  13. Reading the above some love EQ mounts, some an Alt-az. When I bought my first scope in 1979, an Alt-az was regarded as very second class, a beginners’ mount if you couldn’t afford an EQ. Thankfully times have changed and the Alt-az is preferred by many including myself. If any new folks are reading this, please don’t take it that the EQ mount is not worth having. For many, EQ is the way to go, it’s simply a case of finding out what suits YOU, not someone else. Ed.
  14. Great video from Ed Ting. There’s of course so many factors to consider that will point to what’s best for us. These factors can easily change as time passes, I’ve listed few of these - Age and physical ability. Of course finances. Low tech to high tech, or the reverse if the technology is a pain in the derrière. The shift from observing to imaging or the reverse. Where we live. Who we live with. Local light pollution. The realisation that we have accumulated so much kit that rarely gets used, so declutter, sell off most of it and simplify your astronomy for the better. So much more….. Ed (not Ting)
  15. Indeed many of us have sold stuff then regretted it……. …..…like when I stupidly sold my wonderful AstroSystems 8.5”
  16. I’ve found the 5mm BST works quite well in my 10” f.4.8 Dob. It’s certainly not premium but neither is the price!! I have a set of TV Radians, they’re definitely better especially towards the edge of field. But with the BSTs, if you don’t mind extra nudging to avoid the edges I personally think they’re very good. If you also take into account the very low price of the BSTs they are excellent But you may find that in your 300p the previously recommended 8mm BST gives a high enough top magnification. Ed.
  17. Indeed that’s correct and is well worth mentioning. Having said that it can depend on what the scope will be used for. If it’s for faint galaxy hunting then a large thin mirror could rest on heavy duty bubble wrap. Hardly good enough for general use but ok for faint fuzzies. Sometimes called a “light bucket”. Ed.
  18. The primary cell on my 10” f4.8 Orion Optics Dob is also the earlier basic 3 point. And yet with such a basic support I get excellent views. I’ve always thought that Jupiter is a good test of optical quality. In decent conditions details in Jupiter’s cloud belts are a joy to see, the GRS is obvious, moon and shadow transits crisp. It does make me wonder if the later multi point cell design is really necessary. I don’t go entirely on theory, just judge by the results. Ed.
  19. Hi Stu. Indeed mirror movement can affect collimation. I feel certain you’re aware that mirrors must never be clamped in place. But I feel that can be taken too far, for instance with regard to clearance between the optical surface and restraining clips I’ve often seen “credit card thickness”. Whilst I appreciate that the intention is not to clamp the mirror, the thickness of a credit card is enormous with regard to that purpose. Perhaps the thickness of writing paper is more appropriate. Another factor is radial support. Large mirrors are often held in a sling, but somewhere around 12” diameter or smaller (in other words that’s the majority) most have radial support at each mirror clip. Again the radial supports only need a smidge clearance to avoid clamping. All of the above means that mirrors are held without clamping, but avoiding too much clearance that allows mirrors to shift, thus losing our carefully tuned collimation. Ed.
  20. From your description you have a multi point mirror cell with triangular supports, each triangular support having 3 contact points using cork pads. You’ve mentioned using double sided tape on the cork pads. You can obtain double sided sticky foam tape much thicker than the regular tape. I’ve used that to good effect by not using cork pads but instead two thicknesses of sticky foam to make a thicker pad. This supports the mirror without introducing stress on the glass but holds the mirror with less chance of it shifting around and messing up collimation especially when transporting the scope. I buy better quality outdoor foam tape rather than from Poundland or similar. If it were me, I’d dismantle the mirror and cell to investigate. Remove all bolts and run a thread cutting tap through each hole to ensure a clean easy running movement without any snagging. Do similar with all bolts using a thread cutting die. When assembling thoroughly clean the threads and use a very small amount of grease on the threads to ensure smooth snag free movement. As already suggested get some strong springs. Many collimation springs I’ve come across have been too weak. If you can compress them at all with your fingers then they’re useless. Collimation springs can be checked for adequacy before using, it should only be possible to compress them in a vice. If the collimation springs are strong enough then locking bolts can often be dispensed with, or alternatively used just tighter than by hand to give a bit of extra support to hold collimation better. My first scope was bought second hand in 1979. I quickly learned to hate those pesky locking bolts for the same reasons you’ve mentioned. Hope you sort it, Ed.
  21. Good thoughts. I’d go 25/12/8/5 myself…….but there’s so many ways to do this…….I’ve had a scope since 1979. Over the years I’ve swapped eyepieces and changed my mind so many times. It’s easy to get hung up over minute details about eyepieces and forget the magnificence of the universe we see through our eyepieces and scopes. Fussing over our equipment can rob us of the joy of……looking Ed.
  22. Of course, it’s your call. But if you have the 25mm BST, then for me the 18mm would be too close in magnification. I’d go for the 12 or 15. I prefer a larger jump from low to medium power, then closer with increasing power. As always, your mileage may vary….. Ed.
  23. Try ENS Optical Birmingham. An email may turn up something not shown in their online listings. Hope you sort it, Ed.
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