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Thoughts on this scope?

  1. Oct 14, 2015 #1


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    I've got a 6" reflector, which I have fun with. I know just enough to get myself in trouble.

    My friend is eyeing a scope too.
    This looks like a pretty sweet setup.
    Pretty big for a refractor. I've got aperture-envy.

    Your opinions?

    My thoughts:
    1. The description can't decide if it's a 102mm or a 120mm.
    2. You never know if the mount is sturdy. A place scopes often cheap-out.
    3. No idea how to assess the motor. Easy to install?
  2. jcsd
  3. Oct 14, 2015 #2


    Staff: Mentor

    I have an Orion 8" Reflector on a Dobsonian mount (no clock drive or computerized star finder). Its great for looking at stars randomly but I never know what I'm really looking at.


    I also have a smaller Orion Cas-Mak scope which doesn't gather as much light but is lighter and easier to setup for casual "don't know what I'm looking at mode either but I have an idea of the general direction" mode of viewing.


    I think the StarMax 90 went up in price, I remember paying $200 not $400 though I could be wrong.

    When I was looking for scopes I focused on light gathering and clarity so that meant bigger mirrors/lenses not more power although I do have two barlow lenses to increase the power a bit.

    And there's this Mak-Cas with 127mm mirrors which may be comparable to your 127mm:


    I tended toward reflectors as more bang for your buck in a scope whereas refractors could be used for terrestrial viewing.
  4. Oct 14, 2015 #3


    Staff: Mentor

    I'd go with the 120mm for more light gathering although you need to study the specs to see what else varies.

    Here's some pros and cons on general telescope buying where they prefer reflectors over refractors and larger aperture over smaller.


    One review for your motor mentioned it didn't fit the Celestron he had so you might want to check with the seller about the scope and drive compatibility.
  5. Oct 14, 2015 #4


    Staff: Mentor

    Also I have to mention my first scope an Edmund Scientific red stovepipe reflector with absolutely terrible lensing but I never knew until I compared it to my Orion's.


    ( I couldn't find a better picture than this ebay ad)

    then I graduated to binoculars 50mm until my arms got tired and I got neck cramps.

    Anyway, with colder months coming up viewing should be a lot better too except for the snow you guys get.

    In Texas it mostly gets colder with the ocassional ice storm every five years or so.
  6. Oct 14, 2015 #5


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    if you are only considering visual, that 120mm scope would be ideal on a non-motorised mount
    the mount looks similar to my motorised HEQ5 PRO mount,


    just a little lighter and without the computerised drive. It would be great for visual work.

    if you have any inkling at all, of maybe wanting to do photos through a scope then I would seriously suggest you get a mount that is already
    motorised rather than trying to add on some after-market adaptor ... it will save a lot of "making this work with that" hassles

    Celestron are a great brand for scopes they have been around since the 1970's
    my main scope is a 9.25" reflector

    fortunately it was $2000 cheaper when I bought it 3.5 yrs ago

    keep us updated
    ask more Q's if needed before your final purchase decision

  7. Oct 14, 2015 #6


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    Looks like a nice scope, nearly 5" achromat [curious they dont mention that, but, it is]. The CG4 isnt a great mount but adequate for that scope. The add on drive is not the best, but, again adequate if you have a little patience. I would say it is worth the money, perhaps even a bargain, at the advertized price. Scope prices are getting more competitive these days- good for consumers.
  8. Oct 15, 2015 #7


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    I was wondering about this too. Thanks.
  9. Oct 15, 2015 #8


    Staff: Mentor

    On the mount issue, also make sure its a rock solid mount with no vibration. On one of my mounts, the slightest touch sets the starfield jiggling around. However, its a lot better than holding binocs but not good for photography/
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