Comparing Fiddletown to Coe

by Jim Bartolini, Mark Wagner, Bruce Jensen, Richard Navarrete,

Jim Bartolini

From: Mark Wagner

Saturday, when I arrived, it was almost completely clear skies. Before dark, there was dew on my observer's chair seat. After dark, the temp had dropped to a low of 35 degrees F, with relative humidity up to 98 percent. I tried a chemical toe-warmer taped to the metal can housing the secondary mirror in my 18" Dob, and that was sufficient to clear the dew.......

Hey, Mark, you should have gone to Coe instead. No wind (just a light occasional breeze), no dew, clear skies (albeit a bit soft), temps probably in the low 40's, good company -- the best night I've spent at Coe so far (since I had plans for Sunday, I had to leave around midnight, hence I was able to log only 78 'new' faint fuzzies)!

Mark Wagner

Glad to hear it was a good night locally. At Fiddletown we were commenting how much darker the sky was than FPeak (or Coe). There was some light dome from Sacto, but not terrible. I was surprised that my limiting mag was not so hot. I've definitely had better nights at Fiddletown. What do you think your limiting mag was in your 16" Dob?

Jim Bartolini

Well, I was able to pick up galaxies in the mag-15 range. I was rather surprised, considering that the skies weren't really black, even at higher mags. The faintest object I found was at mag-15.7; I had to double-check just to make sure I was actually seeing it (I've found objects as faint as mag-16 at Lassen and Pacheco).

Bruce Jensen

Jim was doing really well!

FWIW, in the 18" anyway, I think the limiting mag. for stars was 15.5 - 16, for typical galaxies about 14.2 maybe, and for Abell planetaries about 14.5 with an O-III filter. Not quite as good as Del Valle last weekend (!) but I think the overall poor seeing we had was as much to blame as anything...the sky was quite clear and the air was fairly dry. The cities of SJ and Gilroy were virtually "uncovered" all evening until midnight; it is surprising how truly horrible Gilroy is for light pollution, even when SJ is right there for comparison.

Despite all this, it turned out to be a pretty productive night, if not in quantity then in quality. It was fun :-)

Richard Navarrete

Yes, it was a nice group. I think there were 15 telescopes or so. There was even a group of us taking astrophotos. Something you don't see too much at the TAC gatherings. I was trying some constellation shots on Kodak slide film. I've never used slide film for astrophotos so I'm very interested in seeing how they turn out. Does anyone know if you can get digital scans of slides at the same time as processing as you can with prints?

Mark Wagner

I was at about mag 15 on galaxies, but nothing dimmer. I finally quit observing when Bootes was completly risen, which I take to be about 3 - 3:30 a.m., and by that time the cold and fatigue had taken their toll.

My object count for the night was not high. I was continuing to work over my Herschel list project, and picking up objects I could not find in the past. This meant that I was hopping around the sky, looking for the dimmest stragglers on my list. I completed several constellations:

Auriga, Perseus, Vulpecula, Taurus, Canis Minor and Monoceros. I also spent some time in Lepus, which had gotten too low for continued observing, I missed out on Fornax, which is interesting looking as it contains some large bright galaxies, poked around in Leo just sweeping the constallation and banging into galaxies (ouch!) all over the place. I finally ended up in Ursa Major, which is no slouch in comparison with Virgo for the "realm of the galaxies" title.

I did find NGC1409 in Taurus interesting, as it appeared to be a very tight pair of galaxies on my planetarium program, and sure enough, I had to go to high power to make them split visually. I enjoyed the field around NGC1550 (also Taurus), as it was involved in a nice galaxy cluster, as was NGC1633/1634 (with UGC3122).

One of the odd things I ran into was NGC2236 and NGC2254 in Monoceros. No matter how I tried, I ended up looking at the same object for both NGC numbers. I wonder if these are in fact the same object?

Other highlights were Thor's Helmet in Gottlieb's scope, The Horsehead (B33) and a very bright IC434 as its backdrop. This was a "no doubt about it" view. M42 was a complete loop of nebulousity with tons of detail.