Saturday, December 31, 2016

Telescope Test: Meade ETX 90 RA (1996)

My new-old telescope, an ETX 90 RA of late-'90s vintage

Had a good time in the wee hours this morning, trying out my free ETX 90 'scope ca.1996. I've got it mounted on an old Meade heavy-duty tripod (I'm well-known in my local astronomical community for over-mounting telescopes!), adding a Sky-Watcher " wedge and cheesy Tasco right-angle finder. The result: a rock-solid mounting for my initial tests on this 90mm Mak.

After a rough polar alignment I sighted the 'scope on Regulus and "engaged" the drive motor. Happily I couldn't detect any delay in the drive wind-up--it started tracking immediately (though at first the noise-level surprised me--this little motor seemed quite loud in the stillness of pre-dawn!).

Went inside to warm-up and get a cup of tea. When I came back outside fifteen minutes later Alpha Leonis was only slightly off-center in the eyepiece, probably more a result of my perfunctory alignment procedure than any error in the drive motor.

So far, so good.

The optics performed very acceptably; the defocused Regulus showed only a slighty off-centered Airy disk, and focused finely all over the field of view, a nicely defined point of blue light.

The only fly in the ointment was the finder scope. As mentioned I had replaced the factory-installed finder (the use of which required a greater level of gymnastic skill than I am comfortably capable of) with a cheap right-angle unit from my spare parts box. Unfortunately the Tasco unit was nearly useless. After only a few minutes I knew that the search for a usable and user-friendly finder would continue...perhaps I might have to invest in one of the Meade right-angle products after all.

As the dawn came up, I summarized the morning's session for my observing journal:

Vintage Meade ETX 90 RA telescope:       FREE
Meade Heavy Duty Tripod:                        $55.00 (Ebay, 2004)
Sky-Watcher Equatorial Wedge                  $65.00

Night under crystal-clear suburban skies with a "new" telescope and a fresh cup of tea: PRICELESS

1 comment:

  1. Thomas L. Epps5/17/2017 01:22:00 PM

    I've since "re-gifted" this telescope to my second cousin, Phillip, whom I have in the past observed with and who needed a capable, versatile 'scope to learn the skies with. I hope the little Meade serves him well, and who knows? Maybe Phillip will use it to begin a life under the stars! There are worse paths to walk...