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  1. Even if the secondary isn't dewing if your observing site has some stray light (street lights, neighbour lights...) then a dew shield can act as a light shield to prevent stray light getting to the eyepiece/reflecting off unflocked tubes
  2. username

    hello all

    Hi and welcome to SGL
  3. If you have lots spreading out it might affect transparency more than seeing. If you can see them well (like when the Moon is out), how they spread out might out might be affected by the seeing (turbulent atmosphere dissipating the contrail quicker). That's just a hunch though, not based on anything concrete
  4. I agree that the means for life are in abundance already. I also agree that the management/truth of them is mishandled. That's about as apolitical as I could make that statement for the forum However over-population is not a myth. We have studied ecosystems for a good while now. We know the effect of over-population of other species, why wouldn't the same fate apply to Humans? Organisms survive through conserving equlibriums. I agree Of course they would keep growing. It isn't any different to Humans moving through different continents on the Earth. We started out as few, now we are many. As the population grew we moved to more resources. We need to start making steps for the ability to move if we need it. That's why I think manned space missions are good and important. Asimov; he wrote some good stuff about over populated worlds, under populated world and their consequences on competition and the susbsequent health of civlisations. The first of the Robot series comes to mind (It's title doesn't at the moment ) Yes unfortunately the cost of manned space missions is hard to sell. The only time they seem to get sold is if someone else is going to get their first. Maybe we should all try together. Go dutch on the tab!
  5. It's good as it gives us practice at surviving off this planet. We need it as whilst I don't believe the situation on Earth is as dire as some make out the projected population numbers suggest it might be a good idea to work out ways of living somewhere else. Have you read any Asimov? A crowded planet is very different to the one we know!
  6. Sorry, I can't edit. The the barlow lens acts like an ~1.5x barlow and now 2x. should be 'The barlow lens acts like an ~1.5x barlow and NOT 2x.'
  7. Patience at the eyepiece is the key to getting the most out of observing planets. With the atmosphere bubbling away above us distorting the image we have to wait for the moments when the best image is available. Also, as the detail on Jupiter is hard to see you need to practice seeing it. It's like anything, practice makes perfect. When I first got my scope I was a bit unimpressed; compared to my old 60mm tasco I thought it wasn't much of improvement. I could see the bands in my old rubbish scope and the same in my new scope. It was only when I started forcing myself to keep my eye to the eyepiece that I started seeing much more. Another thing you might try depending on your type of barlow. On your barlow lens can you unscrew the lens assembly from the bottom of the silver tube? If you can then you can screw this bit in to the bottom of the 9mm eyepiece like a filter. The the barlow lens acts like an ~1.5x barlow and now 2x. Your 9mm gives you 100x at the moment and this will put it up to around 150x. The image won't be as bad as it is at 200x. Still make sure you give the lower magnifications a chance.
  8. Yep you're right, 240x in a 250mm scope isn't pushing it too far. I don't want to go in to exit pupil and everything in the starting out section but keeping the magnification approximately equal to the aperture of your scope in millimetres makes sure jupiter is bright enough for you to resolve the low contrast detail
  9. One thing to remember when trying to view jupiter is that it doesn't take magnification too well. The detail on Jupiter is low contrast, faint brick coloured bands on a cream background, the structure in the bands have got quite subtle colour differences too. When you increase magnification jupiter becomes dimmer in the eyepiece which will make it harder to make out all the faint contrast. My best views of jupiter have been at x100 to x130 magnification. Try and resist the temptation to go to high magnification and keep the magnification to 1 X or 1.25 X your aperture in millimetres. The image will be smaller but much sharper plus if you keep looking you will start to see surprising detail.
  10. my best view of jupiter was also through thin hazy cloud I initially thought the cloud might be acting as a filter enhancing the contrast but I got a good explanation from sgl members the thin hazy clouds are high altitude and if they are up there the atmosphere is less turbulent at high altitude so much improved seeing.
  11. normally set up in a corner of the lounge but if space needed mount goes between a bookcase and wall with scope on a shelf in the bookcase (it has it's own little space)
  12. Fur lined boots and a hefty parka were the best astro purchases I've made recently. Plus thermals and many thin layers on top. I also have some boiled sweets or some tracker bar sort of things in my pocket - you need to make sure you're still producing heat.
  13. Sunday was amazing! The seeing wasn't too bad either meaning I was getting moments of quite a lot of detail in the belts. I was concentrating on that when the Europa transit surprised me. Thanks for all the software tips, saves a lot of time. Faster than getting stellarium sorted. I've printed out an A5 booklet of the pdf to go with my planisphere for the times when I don't feel like turning computer on (I get allergic to them after work ).
  14. Here's a useful list that will tell you which moons are transitting and when http://media.skyandtelescope.com/documents/JphenTab2012-2013.pdf
  15. Hi all, I was out on the 28th October (Sunday) waiting for the Great Red Spot to appear on Jupiter. As I was watching the GRS move across the disc I noticed what I thought initially was a speck of dust or defect in my eyepiece. My initial panic subsided when it moved and I realised I was watching a moon shadow transit! So I was treated to 2 events that night but it's been annoying me that I didn't know what moon it was. I'm having trouble setting up Stellarium to give me reliable data (I have location, altitude and time set up correctly) for Jovian event predictions. I much prefer a bit of paper anyway and I found this on Sky and Telescope web site; it gives the start, midpoint and end of all Jupiter moon events. Hopefully someone will find it useful if you haven't found it before http://media.skyandtelescope.com/documents/JphenTab2012-2013.pdf According to this it was Europa masquerading as dust!
  16. just found this in the equipment reviews section - might be of use http://stargazerslounge.com/topic/30187-baader-ca-filter-comparison/
  17. Also if it's just for planets have you tried stopping the frac down a little bit and just trying a cheaper light yellow filter? Cheaper if it's just for temporary looks and the yellow might help a bit on jupiter.
  18. I see you have a LP filter in your signature? If it's a neodynium type then I've read that you can stack it with a fringe killer rather than a 'semi-apo' to turn it into a 'semi-apo' as the semi-apo is just a fringe killer with neodynium coatings. Might save you some pennies...... I couldn't tell you if they work as I haven't used one
  19. I've been wondering about the clutches.... My intended use would be with a 4 inch mak and short tube frac. I'm reasonably confident I could balance my mak with rings and dovetail side mounted and I'm currently only using plossls and orthos at the moment. What worries me is that with short eye relief eyepieces is if I knock the scopes out of position and weak clutches sound like it may me too much problem with this. Maybe I'd be better putting the money towards something a bit stronger with slow motion controls too as I would want something that can go from low to high mags without trouble I was intending to get a short tube frac as the counter balance as I thought the two tube set up was a nice feature but I'm having a rethink due to possible problems with high mags and short eye relief eyepieces. Thanks for all your replies; I think that maybe if I went the giro route I might be better off waiting until I had a bit more money available for the next size up and a better tripod (and more aperture!) As it stands at the moment my eq2 can do an ad hoc giro configuration and if I tape some coins from the penny jar to the counter weight shaft rather than use the supplied weight I can knock 1.5 kilos off the weight!
  20. Sure is, £55 new in uk at the moment and I got my 9mm for £30 used. Hope they give you good views
  21. Cheat! Of course if you have one of these available use it
  22. I wouldn't bother trying to heat a tent, even in October. You're only going to keep the wildlife warm. Whenever I camp I find the best ways to keep warm is to make sure you eat a lot and where lots of thin layers. Make sure you have clean clothes to get in to in the tent if you manage to get wet outside. Buy yourself a decent sleeping bag - if you can't afford a high tech one get down the army surplus and get a down filled one (these cannot get wet though). If your sleeping bag is up to scratch then don't wear too many clothes when in it - they work by reflecting heat back on to you and you're producing the heat. As for a shed I've always thought one of those fan heaters are good - the shed isn't insulated too well either so rather than trying to heat the thing up just have hot air blowing on you if that makes sense?
  23. Cool the mak isn't longer than a C6. I can't see myself getting any longer tubes in the near future as most of my observing is done in cramped spaces. I have seen some berlebach photo tripods that are reported to be fairly stable with the central column raised, I don't think that would be true if it was raised too far though. I was considering a counter weight as there seems to be some discrepancy on the maximum load without one (tele-optic say 2.5kg, teleskop service say 4kg - I'll believe the manufacturer!). I have a bit of time to mull it over as haven't all the funds yet. Thanks again for your help
  24. souhaitez is wish or want I think. You remember your o-level french better than I remember my gcse french! £95 is quite expensive though, especially if you have other things on a wish list
  25. Thanks for the info. I've just had another look at the bolt after looking up M10 thread dimensions and I think the eq2 has one too! Good stuff. It's good that they can carry a C6 as this is a possible future purchase too. I'll have to think about tripods for it later on, the HAL 130 sounds good, do you remember if they had much problem with the OTA hitting the tripod? I suppose it doesn't matter you can just reposition it or maybe get a little pier.
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