Back to Home

Meade Forum Message

Forums: Atm · Astrophotography · Blackholes · Blackholes2 · CCD · Celestron · Domes · Education
Eyepieces · Meade · Misc. · God and Science · SETI · Software · UFO · XEphem
RSS Button

Home | Discussion Forums | Meade Equipment Discussion | Post

Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...
The Space and Astronomy Agora

Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response To
Posted by Daniel Johnson on September 1, 2003 21:15:26 UTC

I own an ETX 90, plux an LX200GPS 10-inch scope. The one gripe I have about the ETX line of scopes is the issue of drive accuracy. It may be good enough for web cam shots, but it is not good enough for long-exposure photography, period.
For visual work, any of the ETX line will show you the Cassini division in Saturn's rings and some of the major divisions in Jupiter's atmosphere.
Although I love my little ETX, it has become mostly a toy or at times a guide scope on the side of my 10-inch scope. In astronomy, aperture is king. Repeat to yourself: Aperture is King, Aperture is King, Aperture... To get as much possible detail recorded with a webcam at 640x480 resolution, you need to operate at a focal length of 4000mm to 5000mm or more, meaning you'll have to use either eyepiece projection or stacked Barlows on even the 5-inch scope. And with a 5-inch scope, the image will be too dim for most webcams to record well.
For the money, consider the LXD-55 line. Either the 8-inch SCT or the 8-inch Schmidt-Newtonian would be reasonable, with the SCT being better suited to webcam imaging because of its longer focal length. There are many accessories available for SCT's that you can add later, and the LXD-55 mount is supposedly better mechanically than the ETX line.
The one advantage to the ETX line: they are compact for transportation and storage. If you have a garage where you can leave your scope set up full-time, an LXD-55 on a set of Wheely Bars (sold by JMI) will have you out and observingwithin minutes. If you have no such garage space and minimal storage space, the compact nature of the ETX line might make it worth considering.
If you look at the beautiful planetary images in Sky&Telescope or Astronomy, you will be unlikely to find any made with scopes smaller than 8 inches. If I were going to spend money on anything smaller than 8 inches, it would be on a good refractor, not a Mak.

Follow Ups:

    Login to Post
    Additional Information
    About Astronomy Net | Advertise on Astronomy Net | Contact & Comments | Privacy Policy
    Unless otherwise specified, web site content Copyright 1994-2024 John Huggins All Rights Reserved
    Forum posts are Copyright their authors as specified in the heading above the post.
    "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET"
    are trademarks of John Huggins