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Subject:  Telescope talk Date:  2/6/2002  9:19 PM
Author:  TMFOrangeblood Number:  136 of 1833

jiml8 said: My wife teaches astronomy at an area university, and we have the school's 9 inch reflector set up in our house.

With the new blood in here from Selena's post, this seems a great time to get some advice on a couple of telescopes I'm considering. Below is the text of an email exchange I had with someone who just bought an Orion SkyQuest™ XT8 Dobsonian Reflector:

...but it hasn't been delivered to him yet. If you're interested in this kind of stuff, please read on and feel free to reply with any help. Thanks!

Him - I recently purchased such a scope from Orion Telescopes and Binoculars ( based on the recommendation of Ed Ting of and the Sky and Telescope review ( that rated it best in its category.

Me - I, too, am considering the very telescope you purchased. However, I think I'm leaning toward spending $40 more and buying the Orion SkyView Deluxe 8" EQ Newtonian:

For the extra $40, I would get an 8" scope with an equatorial mount... and I could throw in another $35 and get the AccuTrack Electronic Drive for the mount... which would allow me to do some limited astrophotography, I think. However, I have the following concerns:

1. The SkyView is f/4, compared to your SkyQuest's f/5.9. I know that gives the SkyView a wider field of view (and better for deep sky objects)... but I read in a book that the faster f-ratios aren't as good for planet-viewing as the slower f-ratios, and I can't quite understand why. Also, the book said faster f-ratios (especially under f/6) are far more likely to suffer from comas and will likely need re-collimating every session. Do you have a