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Moonshane

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Posts posted by Moonshane

  1. To be fair, I am not sure the required parameters have been clearly stated by the OP. Nor have they mentioned kids but having run a space club at a primary school, I'd recommend not underestimating their ability to find things if you spend time with them to show them how. Suggestions in this thread have (in good faith) been made by the members trying to help and offer a range of possible solutions which the OP can consider then buy (or not). People are allowed to disagree on this forum! 🙂

    The original post stated :

    I am new to stargazing - I read seeking help and guidance

    the sky on a clear night is amazing up here!  - decent observing conditions

    looking to buy our first telescope - starter scopes are appropriate

    don’t want to spend a huge amount - £200-300

    don’t want one that is not very good with images. - I presume this means they want one that is good with taking images but not sure? OP?

    As usual, it's this last point that creates the difficulty. It's sort of similar to the creation of rockets. Why bother making all those basic ones when they just fail. We may as well just wait until we can make the final one and this will save time and money. The problem is that you don't know how the final one will work without the experience of the others before them.

    With a stated budget of about £300, there is little doubt in my mind at least, that buying used would indeed be a good option. Especially if bought from this forum when the classifieds become available through forum contributions by the OP. In my mind the option of a 6" f8 or an 8" f8 Dobsonian is perfectly reasonable and does fit within the parameters that have been stated by the OP. They provide a stable platform and with the addition of a red dot finder plus a RACI finder if funds allow, (and a star map) they would have access to a lot of objects while they decide what they wish to concentrate on. If it turns out to be imaging, they can buy appropriate kit and sell or keep the dob. Naturally, they could buy an SCT or a fast refractor too, but these would have more restrictive uses and possibly cost a lot more than their budget depending upon the chosen mount.

    Hope this helps.

    • Like 3
  2. The problem is actually that the answer to your question is that 'it depends'. If for example you are looking solely at imaging, then a large GEM or similar and a smaller newtonian (i.e. smaller than your 200p) would be a good starting point (although even that depends on what you wish to image).

    If you are looking at visual astronomy only then a manual dobsonian would be far more cost effective for a larger newtonian (i.e. such as your 200p) although you would presumably have to make or somehow source a dobsonian mount which might be tricky (relatively easy if OK at DIY though ( e.g. the link below). The eyepiece of a larger newtonian would be very high up on most suitable GEMs and you'd possibly need a step ladder for observing at the zenith.

    That said, it all depends upon budget and available space to e.g. store a couple of options. It's often cheaper to buy a larger dob and a smaller refractor with a smaller GEM than buy a huge GEM to 'make it work' with the gear you have. As I say 'it depends' 🙂

     

    • Like 1
  3. 3 hours ago, col said:

    Yeah for the 2" 30mm, I tried it and sometimes it was too much, again it's a new user thing with me. 

    I'm sure I'll get used to which eye piece needs the extension. But just pulling the Barlow out a little was no problem and easy enough to do if needed. 

    So should I use the extension with the 2" Barlow as the normal thing to do Mr Spock? 

    That's the experimentalist dob owner in you coming out 🤣. We all like tweaking. That's tweaking NOT twerking.

    • Haha 1
  4. 7 hours ago, col said:

    Hi Moonshane

    Thanks for that, that's exactly how I did it. 

    Going on the picture I posted would you say that's collimated? 

     

    Not quite, the dot needs to be perfectly concentric with the circle.

    That said, this won't be the reason for an 'over-exposed' Saturn or Jupiter. That will be either seeing related or just getting your eye in. Sometimes (always) when looking at bright planets you need to stare intently for a minute or so and then detail will eventually begin to emerge. The atmosphere/seeing makes detail on planets go something like, fuzzy, fuzzy, sharper, wow!  This is normal and it's on rare nights when planetary detail is stable and sharp for any length of time. Good luck with the collimation. 

    • Like 1
  5. OK so as I see the pics, the black ones have a spring. These are the collimation knobs. The screws pull and the spring pushes. The white ones are designed to hold the position and should only be done up with very light even pressure once collimation is achieved. I don't have these locking screws on my scopes.

    My recommendation is as follows. Loosen the white ones all the way off until well away from the cell. Then adjust the black ones until your primary circle is evenly centered over the collimation eyepiece hole. 

    Then take the white ones back in until they only just touch the cell. Check the collimation again as this last bit might move it slightly. If so back them off slightly. I doubt they are beneficial unless I am misunderstanding the cell construction.

    This may help too.

     

  6. Is your scope f8 or f11? With my f11 version I find the most used is 11mm (145x) and possibly 9mm (177x). I have TV Delites and they are really good. That said for solar system objects I often use binoviewers and TV Plossls. The 11mm TV Plossl is just as good as the Delites to be honest albeit a bit less comfy.

    I'd try to establish a rough set based around a wide field eyepiece at maybe 50x magnification plus eyepieces from 100x and then increase by factors of about 1.4x so 100x, 140x then 200x you can then adjust in decent increments per the seeing.

    • Like 1
  7. One thing I learned a long time ago is that you should never miss a planned observing session due to feeling that your collimation is not bang on and waste time twiddling in the dark. Collimation is important (as above, especially the final dot in the circle primary adjustment) but if it's off a little you will still see almost the same stuff and atmosphere or your neighbour's roof/chimney or a street lamp will probably have more of an effect. I only check secondary alignment every now and again. Once set it takes some moving unless it's a truss dob.

    In truth if you practice collimation when the pressure is off - in the daytime, with a brew, it will click after a short time and then you will sort the primary collimation at least in 10 seconds or so.

    Keep going, you have a great scope.

    • Like 4
  8. Nice review. I think I have used all of these and still have the two Baader shown. I pretty much agree with all you say.  I like them as accessories make their uses infinite. The Zeiss Baader is my main (actually my only) non solar diagonal and works really well with my binoviewers (Maxbright). The other one is used in my pst type 2 mod.

    • Thanks 1
  9. As well as the above points, other, perhaps less well appreciated factors are that a 2" diagonal often/usually has a longer light path and of course weighs more. This could be a plus or a negative affecting balance and extension to reach focus depending on the scope etc. 

    Personally I like the Baader 1.25" prisms as the connectors available  make their uses almost infinite. I use mine with my binoviewers and also for my pst mod and cyclops mode for night use. I have one 2" eyepiece (26mm Nagler) and there's very minimal issues that I can detect. For that I have a 2" adapter. It's mainly in my case for newts though. 

    • Like 3
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