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derekm

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Everything posted by derekm

  1. Keep an eye on the Lidl website. They have ironing chairs/perching stools on offer a couple of times a year. Mine was £15 a couple of years or so back. See Russ's post of 17 Feb 2010 above for a photo.
  2. There's nothing to go wrong with a sight tube/Cheshire, unless you are ham fisted enough to break the cross-wires! After any collimation, the star test is still the clincher.
  3. Size does matter! If your base is still in good condition, take it apart and varnish or paint all the exposed chipboard surfaces. Then re-assemble and run down all the joints with silicone RTV or decorators caulk. If it has started swelling already, plan for making a new base sometime!
  4. A Strehl ratio of 0.5 would be a pretty poor mirror. See:- http://www.rfroyce.com/standards.htm 1/4 wave, which is Rayleigh limit is 0.82 Strehl and 1/3 wave is 0.71, so 0.5........ .
  5. I guess that as long as people are happy to find lots of reasons for high prices, then they're likley to stay that way.
  6. I've seen a few posts slating the service from S & S and replied to some saying that personally, I've never had a problem. Sunday 6 Feb., I ordered a modest pair of binoculars (for wildlife, not astro). Received an email yesterday saying they were shipped and 1100h today, they arrived. Credit where it is due.
  7. They are expensive, because Brits seem to like to pay a lot;) and our importers find they can get away with it. You only have to compare the US and UK prices and then look further and find the huge differences between some American dealers. The above applies to almost everything, not just astro products. Someone suggested a manufacturing cost of £200. I would bet a pound to a penny that the factory gate price in China is no more than a third of that, possibly less.
  8. That's the one! Thanks a lot Billy. It's in the favourites now and location double checked!
  9. Browsing on here and Cloudy Nights the other day and found a thread showing how to modify an illuminated magnifying glass with red LEDs. I thought I put it in my favourites, but I'm damned if I can find it. Can anyone come up with a link please? I've searched umpteen forums here and CN without success.
  10. Most people say how wonderful their laser collimators are, but they have never compared their results with a Cheshire.............. .
  11. I bought an 8" Dob from Teleskop Service back in 2004 and the shipping for the two huge boxes was only €50, no dearer in fact than UK inland shipping for the same scope!
  12. Being realistic, the chances of making a decent 16" or 18" mirror at home, are fairly thin. To buy a mirror set, Oldham Optical Web Site would be a very good place to start. Otherwise, as suggested, a s/h Lightbridge, and junk the mechanics. There has to be someone out there who has a damaged scope and doesn't know what to do with it.
  13. Seriously, you'd probaly be better working overtime and saving the £2k. Less hours with every chance of a much, much better result.
  14. Don't listen too much to hearsay. Some of the "probably rarely excellent" optics would surprise you.
  15. No 3. 12". Don't need a stepladder, or an observing stool to save the back!
  16. Check out post 91 on this thread for the results of an expert (not me!) test on a Rev. 12" mirror. http://stargazerslounge.com/equipment-reviews/84376-revelation-12-dobsonian-4.html It's a pity you didn't jump in feet first a year ago, as the new price was than only £510 and with a much improved spec. See Telescope Planet Revelation 12" Premium Dobsonian Telescope for latest spec , though the price is now up to £670. In any case, you've got an impressive scope that will last you years.
  17. I've had a few items from S & S and the service has always been perfect. However 3 or 4 years back, our society wanted to buy two observatory domes from Pulsar and even after sending begging emails to them, we could not get any information. A strange way to run a business! We had two domes delivered from the States in about a month - not Pulsar BTW!
  18. The tests done for the pdf review were blind, using the same telescopes at the same time under the same observing conditions. As they were blind tests, it is reasonable to assume they were unbiased. How many of us, with our various brand preferences can honestly say we have arrived at our conclusions in the same way?
  19. This is about the same as the one I use for maintaining a full charge:- 12v Solar Panel Trickle Car Boat Battery Charger on eBay (end time 09-Feb-11 13:41:56 GMT)
  20. RW, get yourself a red dot and a star chart (Sky & Telescope Pocket Sky Atlas is great Amazon.co.uk: pocket sky atlas: Books) and a low power eyepiece. You'll have no trouble increasing the OMG to 50% or more.The only trouble you may have is fighting the EQ as you go around the sky, but that would be the same with an EQ GOTO. If you are careful with your polar alignment the setting circles of an EQ5 should be good enough to navigate with, but chart and red dot are less complex.
  21. Right enough Chris! There's a site I occasionally look at when I'm daydreaming that experiments in "over unity" phenomena. The JLN Labs home page The "cold fusion" appears to have some truth in it. About 5 years back, a British company, Gardner Watts came out with something similar: How this 12inch miracle tube could halve heating bills | Mail Online but since then, nothing has been heard. Patent bought and shelved?? The oil companies wouldn't like it at all.
  22. I can confirm the same, but I don't like leaving my garage lights on 24/7;) I've tried maintaining the motorcycle battery with the same little panel propped up on the fairing, facing the window +/- 10ft away but not enough light hits it, hence my suggestion that the panel needs to be at the window.
  23. I have a 10" x 2 1/2" panel that cost £12 on the Bay and it kept the 110AH caravan battery topped up all year round. It would NOT charge the battery, but would maintain a full charge. The panel needs to be at a window facing preferably south, not just being illuminated by daylight filtering in.
  24. I know it's too late for the OP, but the best thing IMO for a newbie to start with is a minimum 6" Dob, preferably 8" if he has the cash and the space to store it. I started with a 114mm Newtonian on an EQ mount. Saw enough to keep my interest for 3 months. Got sick of battling with the EQ when jumping about the sky (as you do). The next scope, an 8" Dob lasted me 5 years. FWIW I also disagree with the mantra that says "start with binoculars". I can't imagine a better deterrent to a newbie than looking for something you are unlikely to see, in a wobbling, hand-held pair of 8 x 50s. Maybe I'm just odd!!
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