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I have just bought....


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I've just been looking at the brochure. The scope probably isn't bad. It at least has 1.25" eyepieces, so getting better eyepieces is made a little easier.

It is a 4.5" mirror, and some 4.5" mirrors are spherical in figure, but some are parabolic. I have one of each. The brochure says your optimum mag is 125x, and that is probably true. If you have a spherical mirror, it will be your effective maximum, too.

If your eyepieces have the letter "H" (Huygenian), or "SR" (Something Ramsden, can't remember the "S") next the focal length, they are of limited quality, and you should think about replacing them at least with Plossls, in the near future. If they have the letters "K", "MA", or "SMA" next to the focal length, they are Kellners, which are almost as good as cheaper Plossls, but you will want to replace them eventually.

Don't even try to use the scope at 375x. The limiting magnification for the scope is 228 (2x the diameter in mm) and beyond that you just get blurrier and blurrier.

An erecting eyepiece is an odd accessory for a Newtonian scope. They are a bit unwieldy for terrestrial use and it isn't very useful for looking at astronomical subjects either.

You can have a ball looking through this scope at low magnifications, at clusters and star fields. Wait until summer, and turn it on Cygnus at 25x; it will astound you! :shock:

If you want to consider better eyepieces, I would suggest a decent 25mm Plossl, an 8 or 9mm Plossl, and a good 2x Barlow. That will give you a range of magnification from 20x to 125x, which is very useful for most stargazing. I use my scopes in the range of 30x to 125x, very occasionally venturing up to 150x.

Hope this helps.

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bioffman

the scope is ok for a starter scope. My 1st scope was a 4.5" scope my only concern is that the short focal length (500/114) will mean that the scope could easily get knocked out of line and so the image will suffer.

Does the information say if the mirror is a parabolic?

Cheers

Ian

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