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JOC

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Everything posted by JOC

  1. So whilst I appreciate that everything moves relative in time, if I want to see the comet say at a decent hour after sunset, roughly where have I got to look based in Essex in the UK - I was hoping it might show on stellarium on the mobile phone, but I've not had a huge amount of joy in advancing the time whilst being able to still have it as search criteria (novice stellarium user!) - I also tried stellarium online, but again didn't succeed. I've got binoculars so it's easy enough to have a quick scan to initially find it, but roughly where do I need to look. My NW to NE is not my best direction - distant town, next door factory lights and 50ft leylandii, but I can go out on the balcony which probably faces due West giving me best part of an 180 degree view. If it's that good and it's best from the balcony I can always lug the telescope upstairs, but I can't creep about early in the morning here - the rest of the house inhabitants get cross.
  2. The pictures on the first page of this thread are well worth a look for anyone having problems - it should be possible for most folks to get somewhat close to what is shown, seeing conditions permitting. The definitive text on collimation is from astrobaby http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/ It does work, even I succeeded, but you have to carry out every little step no matter how daft it may sound.
  3. That's got a focal length of 400mm with a 4mm in that's going to give a magnification of x100. They say approximate theorectical maximum is twice the apperture in mm - your apperture is 100mm, which would give x200, but I tend to think its about half that in the UK. So, I guess you might get to x100 on a really good night, but I reckon you would be better off with less than that maybe something around the 8mm mark? I don't know what sort of EP's come with these scopes, but I had Skywatchers own 10mm and 25mm come with my 8" and, FWIW, I was quite pleased with them.
  4. The 8" is useable by standing, but 100% more comfortable sitting. I got a couple of cheap, lightweight bar stools and have a high one and a low one. It has to be said that I don't use my scope very often, but IMO the collimation holds quite well between uses. You def. don't need a light shroud, I think it depends on location and what you are expecting to see. If you are somewhere pitch dark, then there won't be any stay light to enter the system. I've got a light shroud (a home-made one), but given the relatively low ability of my 8" to capture light from DSO's anyway I don't find much difference at night with and without it - I actually think the entire system performs better at night without it. for various reasons. You would 100% need one during day time use if used a solar filter to look at the sun - that is always when I do use the light shroud. However, you are looking at a 250P which I think is the 10" isn't it? Since you might therefore be more interested in DSO's that I was (I wanted a first general purpose see most things scope) then I guess you might find a light shroud might give you an edge on seeing those feint grey fuzzies particularly if you are in a light sensitive area. As to fitting a handle on a larger scope - in my case, I wouldn't have wanted the hassle or the fear of drilling into my brand new OTA to fit one. Also if you look at where the handles are often positioned right in the middle of the scopes I am still not sure they look the easiest things to get on the back seat of a car. Now talking of cars, and I've had mine in the car on several occasions what you do have to watch is not as much can you fit the OTA on the back seat? but the question that isn't so obvious is, can you also fit the Dobsonian cradle mount in the boot/on the spare passenger seat? I have a fairly massive Estate Octavia and the Mount def. requires careful positioning - then obviously you want to add in a folding chair, EP box possibly some warm clothes and the space rapidly diminishes - I would def. say to be as aware of the size of the mount if you want to transport it as much as the size of the OTA. Even the mount for my 8" is a respectable size and I have to lie it down in the boot - it is another awkward thing to load in the car.
  5. With experience although it may not contribute to the problem if you look at that picture posted just above I can vouch for the potential of twiddling that big grub screw between the two focus knobs by accident in the dark. That locks the focus and then any amount of twiddling with the big knobs won't change it - make sure it has not been tightened by accident. I also agree that the flex tubes seem to be correctly positioned. FWIW you are looking for yours to look like my smaller one when it's ready to use - mind does actually do the two position clicks referred to above, but if yours doesn't then providing the rods are extended apparently as much as mine they should be correct:
  6. I've got an 8" Skywatcher flex-tube. I've been very pleased with it and given the chance to buy again would not buy the solid tube. I love the way it collapses - this makes storage easier - my 8" folds to about the size of a dining chair to store on its base (though your contemplated model would obviously have a wider base). Other things I like are the folded size when it comes to moving it. I store it inside the porch and my goto base weighs a bit and I find it easier to move the OTA and the base separately (it is a work of moments to separate the two) . The advantage of moving the OTA comes when it collapsed - it is an easy reach to pop my fingers around the open end and under the ridge at the closed end and lift it safely within an arms width which makes it easy to move through household sized doors. I don't know what the collapsed size of the one you are looking at is, but I imagine there would be a similar advantage - my arms are not that long and if you are a taller person than me you might still find the collapsed tube of a larger model is still an easier lift to shift through small spaces than the longer length of a tube that won't fold. FWIW I have not found any issues with a possible loss of collimation and the tubes of the Skywatcher provide an entirely convincing rigid immovable structure when locked into place. I'd buy again. FWIW here is a picture of my 8" you can imagine the difference in size when folded. The two pieces entirely butt up against each other and the whole length of the extension rods is lost.
  7. JOC

    Expensive!!!!!!!

    Well at least when you decide to replace the telescope you'll have some decent kit to put it on./on it I hope it works OK for you.
  8. No need to wait until you build your scope, hand her a pair of binoculars and see what she can see on the moon, also, if only building for your granddaughter she might get on better with a small tabletop Dobsonian, which may well be sufficient to see rings around Saturn and moons around Jupiter and could come in around £100 second-hand - could you build for less? You would also have a solution for her far quicker. You could always sell it once you have your own larger model. For that matter you can buy a brand-new 200P for £289 or many decent scopes for less than that second-hand. It just sounds a rather long-term project for a first telescope when you could both be enjoying the sky a whole lot sooner with an off-the-shelf solution that would be guaranteed to work and get finished! Just a thought 😄
  9. I'd love to know how you all get the foam cut so neatly and flat in the bottom of your 'holes'. I couldn't work out how to achieve that and dug the snips in and cut the upright bits of foam at an angle, but it makes the case look less than tidy
  10. I guess so if you have cash to burn, but I've never picked up a 2nd hand EP that wasn't within a whisker of being like a brand-new one (all mine have come via SGL) and I have a set of Morpheus for around half the cost of buying new - it's well worth considering.
  11. That's one bold choice as a first scope - hope it's everything you hope it will be. FWIW: The Pentax come up from time to time second-hand - that's where I got my one and only, but the Baader Morpheus I can tell you that I kept an eye on SGL classifieds and in about 18mths or so I had amassed the complete collection of these in nearly new condition, so it depends what time you have to spend on things. Maybe get a decent long and shorter length EP now and then bide your time and see what comes up second-hand?
  12. LOL, I was also kind of looking at it from the persepctive of using the degrees up and down (and left to right, though that won't so affected) that are published for any given object. If you have some form of marker on the telescope for vertical degrees and a reference says that Saturn is at 10 degrees altitude it won't be any good setting the marker on the telescope for 10 degrees if the telescope is already sitting hundreds of metres up. There must be a standard adjustment that can be used, i.e. subtract 1 degree from the published figure for the object for every x metres the scope is sitting above sea level?
  13. That won't account for altitude though will it?
  14. You can make a home-made shadow finder with a nail tapped into a piece of wood that casts a shadow onto a back plate - get the sun where you want it and mark on the backplate where the top of the nail's shaddow is - or for not of cash you can buy a simple solar finder - I strap mine to my scope with a bungee, but you have to adjust it with each use. However, just as a tip - and it only works safely if you have a solar filter that covers the whole of the front of the scope like mine I find a useful thing to do is to take out the EP and look directly through the focus tube - with the shadow finder getting you close and I also find you can use anything that sticks up on the telescope to help, like a nut head it seems far easier to adjust the tube to find the sun in the mirror if you don't have it magnified, you can sort of see the glow as you approach and then big circle sun directly in the mirror - I have a huge amount more success that way, but you ABSOLUTELY MUST have the whole of the OTA covered with solar filter like in my picture
  15. Won't it be necessary to adjust the measured horizon relative to how high the OP is to begin with . Surely the star measurements are taken relative to sea level horizon. If the OP is in a Valley which is still 100m above sea level then does this need to be adjusted for. For example in some instances you might be looking down to a horizon? Either that or I've missed something huge in my thinking.
  16. I don't know what you can use software wise, but I have had experience that sometimes USB leads are very specific for certain applications and you can't just use any old USB lead in certain situations.
  17. Just an idle thought - if the OP is imaging I imagine this calls for a very calm and stable environment. Is there any potential problem arising from possible vibration from the proposed fans?
  18. That's quite lovely, you are so clever - I can't sew for toffee. Well done, I'm sure it will be a much appreciated square.
  19. Given the duration it was built in and the current situation how about 'The Rainbow Rooms' or 'The Rainbow Roller'. Unfortunately Bryant's Obsy gives BO!! Or how about The Voyager Complex as you are looking into the depths of things billions of miles away and Voyager is the farthest thing from earth at the moment.
  20. I have an 8" 1200mm FL Dob and I have never got any joy out of anything more magnifying than a 4mm and most times a 5mm. I have once tried a 3mm in it and it was hopeless - in my opinion I think it you stick at half of what is theoretically possible you won't go far wrong. I would 100% buy the 4.5mm if you have to get one of them, but I reckon you'd be better off stopping at 5mm IMO.
  21. Psssttt.....Southern SGL members - it looks from the postings above that the clouds should be in North of the UK for the next few weeks!!
  22. Interesting........but I bet they still have a bit more under their belts than a 300P!
  23. No, I don't think so, in fact I don't think there is any scope out there size wise that makes stars look like discs (the only exception being Sirius which the atmosphere often renders as a monster raving party star light show). The jump from what I've got to what you have scope wise is very slight. It might permit slightly more magnification of something like a true planet, but it is marginal and would require decent conditions to improve hugely on the x200 or x250 which is the ultimate maximum I get from my scope. What your larger mirror has purchased over mine is the ability to catch a bit more light to render DSO's more clearly - which might be why you have succeeded with the cats eye nebula, you might just have tweaked that into better focus too - you will be able to push very slightly more magnification of objects that I can, but it won't be huge. Though if that's the best you can manage on Arcturus and Vega I'd surprised if you got sufficient focus to get the best views of the cats eye nebula and maybe you have been impressed with a less than ideal view of that too. I doubt you will get much use out of and EP smaller than around 4mm in UK conditions - I top out at around 5mm on a good night. I guess it might be worth checking the collimation of the scope http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/ Follow the linked to guide to the letter no matter how odd the instruction and you won't go wrong. I can't advise on the focusser set-up, but there will be folks here that will know if it looks correct. You certainly are not getting the best view your scope or EP's can offer if you can't improve on the shots of the stars above - you absolutely need to resolve those bright pinpoints of light.
  24. Well not that I know huge amounts about these things, but they wouldn't look like that in my beginners system I'd see points of light, OK, bright points of light, but points of light nonetheless. Those pictures have got more in common with something like Venus or another brighter planet (though it is bright even for saturn and not the right shape, even out of focus, for rings around a disc), but even then you shouldn't be seeing the diffraction spikes. If you have no more travel left in the focusser to get pin-points of light have you got any necessary adapters etc. in place? Have you perhaps upped the magnification too much and got to the point when all you are seeing is a hazey blob, or did you have dew on the mirror? If that's what you are seeing, even in my experience as a rank amateur, that doesn't look correct to me. Perhaps someone more experienced will be along to comment. NB. Andy is someone different 😉 NNB. I too would stick with the BST's if you have them, your scope is somewhat similar to mine and the BST's should be ideal once you get the focussing sorted,
  25. Spheres of light - I was under the impression that most stars except Sol only gave points of light - were you in focus?
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