USER OBSERVATIONS Last updated: 17 December 2004

Subject:	ETX-70AT Lunar Observation Report
Sent:	Wednesday, December 15, 2004 07:31:47
From:	Gordon McGowan (gordonm7a@yahoo.co.uk)
Lunar observation report, 04th December 2004, 0700UTC, Nottingham, U.K.

I got up early on Saturday morning, despite recovering from a cold to
image the Moon, as the sky was perfectly dark and transparent for this
suburban location. The Moon was riding high in the sky south southwest,
clear of the trees surrounding the garden and perfectly placed for
imaging. I was surprised the see it at third quarter phase, as I hadn't
planned this session and it appeared magnificent, stark white. I quickly
assembled the ETX-70AT, plugged in the portable power supply, and
aligned the scope.

Attaching the BC&F The Ultra afocal camera support to the 10mm Lanthanum
eyepiece was a bit like wrestling with Meccanno and I had to be careful
not to drop the tiny allen key necessary to adjust the mount. I fitted
the Nikon Coolpix 4300 digital camera and aligned the lens with the
eyepiece to allow zoom movement without vignetting.

The sweeping curve of Montes Appeninus was clearly visible with the
crater chains Ptolemaeus-Alphonsus-Arzachle and
Purbach-Regiomontanus-Walter prominent on the terminator. Maginus and
Clavius displayed dominant huge walled plains to the south. The broken
ramparts and central peak of Anaxagoras were sunlit in the north. Montes
Alpes were partly visible, but the Valles Alpes was sadly out of view,
hidden in shadow. As always, it was difficult to focus accurately using
the small LCD camera screen, but the contrasted craters on the
terminator made the best targets. Tracking had to be manually adjusted
at high magnifications with the Autostar.

With the 3x Meade barlow the bright scarp of Rupes Recta, the famous
"straight wall" was clearly visible, though fringing was minimised with
a Baader contrast booster filter. On the edge of the lunar disc the
slight broad depression of Montes Cordillera to the southwest of
Grimaldi marked the edge-on location Mare Orientale, the most recent and
perfectly preserved multi ringed impact basin on the lunar surface.

Later, after the session, I had a local professional minilab print one
of the full phase frames at 8 x 12" (the largest size they could machine
print) and framed it in black. The typical reaction of colleagues at
work was stunned awe: "Is that one of yours?" followed by silent, steady
gaze at the black and white print. One manager broke off work to make a
point of discussing the print informally: "That is a magnificent
photograph". Fulsome praise indeed, (from non-astrophotographers, of
course) but I was lucky as day 21 is one of the most spectacular views
of the lunar month. Personally, I was a little disappointed at the
softness in the image, but have to take into account it is not bad for
such a small telescope. Actually, I think the Meade optics live up to
their legendary reputation despite my concerns that the ETX-70AT might
fall optically short of the Maksutovs, being a crown and flint glass
achromat (ah, if only Meade would produce an Apo version, like the Tak
FS60...) In the colour version of the print, violet fringing was quite
well controlled, which surprised me. The image could do with processing;
stacking and sharpening in Photoshop, and be printed about half a grade
harder to darken the maria. But not bad for a raw, unmanipulated print
from afocal projection. I'll try to image the Moon for each day of the
lunar month. That will make a good, basic project and build some skill
at astrophotography.

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