From: utzoo!decvax!pur-ee!rdu Newsgroups: net.space Title: neophyte seeks telescopic expertise Article-I.D.: pur-ee.388 Posted: Thu Jul 1 19:58:20 1982 Received: Fri Jul 2 01:11:10 1982 In the course of my unschooled browsing for a first telescope I have encountered a curiosity: two telescopes whose specifications seem roughly equivalent and yet whose prices are disparate. The two are the Celestron C90 and the Questar 3 1/2. According to their brochures they have the same design (Maksutov-Cassegrain), aperture (3.5 inches) and approximate resolution (1.0 arc seconds for the Questar vs. 1.3 for the C90). The C90 even achieves a higher "maximum useful" power (210x vs. 130x) and yet the Questar costs about four times as much. Why? I would be interested in others' knowledge or opinions on what makes a good amateur telescope, because apparently my original intuitions (light- gathering, resolution, power) are inadequate. How do different designs compare? (Here I would consider actual experience more telling than theory.) How important are special lens coatings? How real are qualitative considerations like sturdiness and workmanship? Sign me In the Dark in Indiana [ Mark Raabe (pur-ee!rdu) Purdue Library Systems ]