I drove Harvey, my six foot three and a half inch tall white Celestron 14, to Fremont Peak (California) State Park, on Friday and Saturday, August 14 and 15, 1998.
The C-14 continues to work well on the Losmandy G-11 mounting -- setup and takedown are a rather leisurely half hour, or a very rushed fifteen minutes. The hard work is getting the 24 Kg (52 pound) optical tube assembly up into the dovetail. That works best for me with the counterweight shaft pointing east and the dovetail slots vertical, and with a chain wrapped from counterweight shaft -- which is bare of counterweights at the time -- to a mounting leg, to keep the moving parts from swinging once the OTA is in place. I lift the OTA shoulder high, corrector-plate end up, and slide it down into place. When it's time to take things apart, I turn the tube to look at the ground, install the chain, remove the counterweights, and slide the tube down to clear the dovetail.
Seeing at the Peak was not very good either night -- a tropical storm off the coast of Baja seemed to have sent some warm, moist air our way. There was a smattering of cloud late Friday during the day, and a thunderstorm offshore -- well clear of the observing site -- in the evening. On Saturday there was enough wind to bother big Dobsons a lot. I noticed it with Harvey -- more so with the dew shield in place -- but I was limited by seeing to about 250x in any case. That was just about right for many deep-sky targets -- I prefer about a 1.5 mm exit pupil for observing galaxies -- but just loafing for planets. Jupiter and Saturn showed tantalizing hints of rich detail when the seeing was steady for an instant, but those instants were never long enough for me to see what all the detail was. I experimented with the Vixen 8-24 mm zoom eyepiece that I bought recently -- its magnification range with the C-14 is 163-489x. It was again interesting to see how small variations in magnification made great changes in the appearance of the image; the cutoff for an aesthetically pleasing planetary view, in the seeing conditions that obtained, was very sharp, and would undoubtedly have changed with different conditions.
My main current observing program with the C-14 has two components -- planetary nebulae and grouplets of galaxies. Veteran planetary nebula observer Jay McNeil has EMailed me his list of interesting planetaries -- over four hundred of them -- and there are lots more, even on the amateur atlases like _Uranometria_2000.0_ and _Millennium_Star_Atlas_. I would have liked to use more than 250x on most of these -- for once past the hundred or so NGC planetaries that I can see from my latitude, it is rare for a few hundred diameters to show more than an irregular smudge with perhaps a hint of a central star. A few planetaries are essentially stellar in appearance at these magnifications, requiring "blinking" with some filter like my Orion UltraBlock, to confirm their identity. (Most LPR filters pass all the light from a planetary shell, but cut starlight by half or more. Thus interposing such a filter between the eye and the eyepiece dims everything in the field except the planetary.)
I have been using _Millennium_Star_Atlas_ to find these elusive targets, because it has more stars than any other atlas I have. Its 11th magnitude stellar limit is just about as deep as the 10x40 finder on the C-14 will go, perhaps a hair deeper. And near the plane of the Milky Way, where most of the planetaries are, there are usually a few charted stars in the field of the 15.5 mm Meade Research-Grade Erfle that I use for 252x. It takes a few minutes to look up the next field on the chart and slew the telescope to it, then a few more to identify the field in the main eyepiece and locate the position where the planetary ought to be, then sometimes a few minutes of staring, using averted vision, and waiting for the seeing to settle -- how odd, to think of deep-sky observing as seeing-limited -- before I can actually see the tiny blur. So far, I can find most of the ones on McNeil's list, even those that _Millennium_ does not plot.
During the two days of the past weekend, I logged about 30 new planetaries, mostly from McNeil's list, but the summer Milky way is to planetaries what Virgo is to galaxies, and often I star-hopped from a listed planetary to one or several nearby ones. They were all faint -- none had either an IC or NGC number. My index-card file of objects viewed is acquiring a lot of entries whose identification starts with "PK" (from the well-known catalog of planetaries).
I did not just star-hop to other planetaries. At one point I noticed a non-NGC globular cluster charted near a few planetaries I was looking at, and took a look at it. It was Terzan 4, at 17:31 -31 36' (epoch 2000), a rather nondescript round glow at 252x, looking rather as M54 might in a 7x50 finder. On Saturday evening, some fellow observers found another non-NGC globular, Palomar 13, in an 18-inch Obsession at 167x. I got a look at it in their telescope, but was too lazy to try for it in the C-14.
After the heart of the galaxy had started to set, rather than climb up the Milky Way in pursuit of more planetaries, I changed target types. I had noticed, as I paged through _Uranometria_ or the _Millennium_ atlas, that there are many places in the sky where NGC galaxies cluster in small groups -- sometimes five, sometimes several times that many. I made some notes of where some of them are, and have been chasing then down with the C-14. 252x is plenty for this work, and I can often see many more galaxies than the ones plotted. Thus I noted five galaxies not far from M92 (NGC 6323, 6327, 6329, 6332, and 6336), and three near M13 (NGC 6194, 6196, and 6197). The latter three are on the other side of M13 from the better-known NGC 6207 and the not nearly so well-known IC 4617. These new galaxies were all fainter than NGC 6207, which shows pronounced elongation and a bright nuclear region in Harvey at 252x, but much brighter than IC 4617, which at the same magnification is also elongated but requires averted vision to hold steady.
Another interesting grouplet of galaxies was centered near NGC 6160. In that area I logged eight NGC galaxies, and found a field full of lumpy darkness -- the sky background looked curdled -- at the location of Abell 2197, a distant cluster of galaxies which I do not believe is associated with the foreground NGC objects. I also looked at Zwicky's Triplet, a tight group of three galaxies near NGC 6241.
Late on Friday night, after the Moon had risen, I noticed an interesting target plotted near one of the galaxy grouplets that I had been looking at; namely, the Draco System, a "local" dwarf galaxy at about 17:20 +57 55' (epoch 2000). On Saturday, I looked for it, using a 40 mm Erfle (Vernonscope's) for 98x. I believe I saw the galaxy, though in cases of such extremely faint objects, it is difficult to be certain that one is not deceiving one's self when one has an exact position to begin with. In any case, I saw what looked like a bright area of sky background, in the place and of the size shown on by the plotted oval on _Millennium_Star_Atlas_. The glow was brightest in the northern portion of the plotted oval. If that was indeed a detection, that makes eight of these elusive objects that I have seen; the others are Sculptor, Fornax, Leo I and II, and Andromeda I, II, and III.
Late Saturday night, after Jupiter was well up in the south, I did a little informal planetary comparison of Harvey with a friend's Astro-Physics 180 EDT, but between poor seeing and buffeting by wind, we were both limited to about 250x, which isn't enough to show all the detail that either telescope can present on a good night. The seeing came and went, and differences in its effects on the two telescopes appeared noticeable to me. At 252x, the Jovian disc appeared for the most part blurry in the C-14, while dancing amoebas for Galilean satellites showed what the problem was. In the AP 180 at somewhat less magnification, the view was not so much blurry as rippling -- the edge of the disc of the planet waved like the margin of a flag in the breeze. Every so often things settled, and both telescopes gave brief hints of more detail, and every so often it got worse, too -- sometimes the edge of the planet blurred out as if someone had taken a dirty eraser and rubbed it around the circumference -- I saw that effect in both instruments.
Many of the people who observe at local sites have exceptionally fine telescopes -- this particular Astro-Physics 180 is one of several that show up regularly. I know from past experience that Harvey is capable of giving some remarkable planetary views, and I am anxious to compare it against these high-quality refractors. But that will take better seeing than we had this past weekend.