OR: Eyepieces, filters, and Mars

Last night I observed Mars using a variety of magnifications and filters on
my 12.5 newtonian. Skies were fairly unsteady but seemed to settle down
with the arrival of a very thin layer of fog.

The observing session spanned perhaps 45 minutes to an hour. Much of this
time was spent going back and forth to the accessory case and matching up a
new EP and filter.

Here's what I used:

3.8mm Orthoscopic
6mm Expanse from Orion
9mm MA from Meade
7.5mm Sirius Plossl
12.5mm Sirius Plossl
18mm Orthoscopic

25% Neutral Density Filter
#80A Blue Filter
#58 Green Filter


The Results:

In moments of good seeing, the 6mm and the 9mm offered the best image of all
the eyepieces. Both performed very well outfitted with the ND Filter. This
filter reduced the planets glare just the right amount
through my scope to reveal fine planetary detail. The Eye of Mars was
pronounced as were the regions to its immediate east and west. The South
Polar Cap was very distinct when the planet was viewed using the 7.5mm EP
fitted with the #80A Blue Filter.

The eastern edge of the planet had a curious white tint to it. Not being an
experienced planetary observer, I wasn't sure what I was seeing. I thought
at first it was something the eyepiece was "adding" something to the image
but the effect was present through all the eyepieces. Clouds? A storm of
some type on the surface? I tried different filters to see how or if they
altered this whitening of the edge. It shown through them all with pretty
much the same relative intensity.

Cartes du Ciel revealed Deimos 49" away from the planets disk in
approximately the 2 o'clock position (taking in account the image flipping
inherent in astronomical scopes). This seemed a respectable distace so I
decided to concentrate on seeing the little moon. No luck. My inability to
observe the Martian moons is a major disappointment.

At 11:00 p.m., Lake Stevens time, I called it a night and brought the
telescope in the house. I seemed to be slightly frustrated with the
evening. Perhaps this is because of my relative inexperience in observing
planets.
Then again, maybe I'm realizing that Phobos and Deimos will always escape my
detection with the present telescope at my present location.


Martin