Last updated: 16 January 2006
Subject:	Observation Report
Sent:	Sunday, January 15, 2006 09:21:53
From:	The Brown Family (
Once in a while, you get a night like this...
Chris Brown

Backyard Observing with the ETX-90 M.

I live in Orange County, CA, and I don't get the chance to find a dark
sight often enough, therefore most of my observing is in my own
backyard, with my highly portable ETX-90M / 884 combo.

Over the years, I've learned that atmospheric stability is much more
important than actual clarity. Typically, on the city nights when
naked-eye stars are abundant, the atmosphere is in a frenzy, and my
little ETX gives out at 100x! The trick in the city is patience. I
usually get home from work, put the ETX on the patio, have dinner, and
take a look about 90 minutes later...if I don't like what I see (75% of
the time!), I pack it in. About 20% of the time, the sky cooperates, and
I spend the next 90 minutes observing.

The big payoff is the last 5%!  When the atmosphere is ultra-stable.
This is the time when you really find out what your telescope is capable

Two nights ago, I caught one of these nights. The moon was 20 hours away
from it's second quarter, so I thought I'd search for craterlets on

Using Celestron/Vixen Flat-top Orthos in 12.5mm, 9mm, and 7mm formats
(Fantastic eyepieces, and parafocal!), I could immediately see the
center craterlet of Plato, but what surprised me was the appearance of
it's close companion, flashing in and out, along with the "averted"
presence of two other craterlets, on opposite rims of the crater! The
9mm eyepiece (139x) gave me the best results, and at times, I saw 4
craterlets at once, a feat I have never accomplished with my ETX-90! I
decided to try Castor next...

I started with my split with a 15mm Axiom, then my 20mm Erfle, then a
26mm Celestron Plossl (Taiwan!) and even at 48x, Castor's split was
obvious! Finally using a 32mm Sirius Plossl at 39x, I got the components
to meet!

The Orion Nebula was next, My 32mm easily splitting the trapezium at
39x. Vivid Nebulosity, and a fifth "Trap" star started at 62.5x (20mm
circle-T Erfle), and at 100x, The Nebula showed waves of light and dark
coloration, layers were visible!

Saturn was now at a good elevation, and it seemed to take all the
magnification I could throw at it! The 12.5mm Vixen Ortho showed a very
bright image and 3 moons, with Titan out of the FOV. Using the 7mm Vixen
Ortho, good for 178.5x, The image was tack-sharp, the ring's shadow was
clearly visible on the ball, as was a couple of bands!

The Cassini Division was easily obtainable at 100x, and I just started
loosing a little clarity at 208x (6mm circle-T Ortho), which is a far
higher magnification than any 90mm telescope has a right to operate at!

Actually, a couple years ago, during Mars' close opposition, I was able
to use 208x successfully on Mars!

That was probably a once in a lifetime opportunity! I had my ETX-90
parked on the patio every night for two months straight!!

The ETX-90 and a stable atmosphere...a great combination for backyard

Chris Brown

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