I arrived at Fremont Peak, near San Juan Bautista, California, at the end of twilight on 30 May, 1998, with my 5-inch f/9 Meade ED doublet refractor. There was a scheduled program at Fremont Peak Observatory that night, and since the 30-inch telescope was down for repairs, many of us had volunteered equipment for public viewing. A fat waxing crescent Moon lay high in the western sky, but afternoon clouds continued into the evening. Possibly for that reason, attendance was light: No public viewers visited my telescope all night. Yet there were plenty of other telescopes, both larger and better.

I wanted a good southern horizon to see the summer Milky Way Messier objects. To get it, I set up where a tree blocked the Moon. Clouds limited deep-sky viewing for the first hour or two, but seeing was very good, so I looked at double stars. At 163x, epsilon Lyr -- the double double -- was wide open, as it should be with this aperture, so I turned to zeta Boo. This star has been closing rapidly, and was a tough split for several six-inch instruments last month. The ephemerides I have show separations to the nearest 0.1 arc second at ten-year intervals, and I could wish for less coarse information: My sources show separations of 1.0 and 0.8 arc seconds in 1990 and 2000 respectively, but an extra digit in both space and time would be most interesting.

In any case, the five-inch showed zeta Boo definitely notched at 456x (2.5 mm Vixen Lanthanum eyepiece), as did a late-model Astro-Physics 130 mm f/8 EDT, also at high magnification. The observer beside me had one of Peter Ceravolo's fine 216 mm Maksutov Newtonians, which showed zeta well split at somewhat more magnification. The seeing was good enough that a 17.5-inch Newtonian separated it, too. The owner of that instrument had some off-axis aperture stops: He obtained notching at 5 inch-aperture, and elongation at four inches.

Most of us were using more magnification than necessary. I did so to be sure to get a good look at the details of the two stars' merging diffraction patterns, and was too lazy to pull out another eyepiece.

Later in the evening, some of us were looking at Antares, whose wide, relatively faint companion usually appears pea-green by contrast. Antares does not rise very high from our latitude, so seeing often restricts the view, and sometimes makes for puckish results: I remember an evening when I obtained a separation with my 90 mm fluorite refractor when a 180 mm Astro-Physics set up nearby -- a fine instrument! -- was bothered enough by seeing not to be able to resolve the companion. Tonight, however, the 130 mm EDT was doing better than my 127 ED. That was no surprise, since not only is the 130 an apochromat (Meade's advertising of their ED doublets as apochromats is false -- the 127 is an achromat, albeit a rather good one), but also the 130 has a better figure than my Meade. However, the precise difference was interesting. At 456x, the Meade showed Antares pulled out into a tiny spectrum, of length about twice the diameter of the Airy disc. The image resembled lateral color -- an eyepiece fault -- but it remained the same no matter where I put the star in the field, and no matter how I rotated the eyepiece. The diagonal used a mirror -- no dispersion there -- and when I tried Vega, much higher in the sky, without no change in eyepiece / diagonal / focus configuration, I saw no trace of the phenomenon.

Atmospheric dispersion can cause such an appearance -- the layers air air act like a weak prism when viewed obliquely -- and the streak of color was vertical, which is what one would expect from that source. Yet AP 130 showed at most a tiny trace of dispersion of Antares's image -- less than a tenth as much as the Meade. It was set up only about 20 meters away, and while I was prepared to believe that seeing might change over that distance, I did not think stratification could greatly vary, particularly on a night of such good seeing. I finally began to suspect my Meade was more susceptible to stratification of air within the tube, or perhaps to tube currents, than the Astro-Physics. At the moment, that is my working hypothesis for the phenomenon's origin, but I have no clue why the two telescopes should be so different.

Both the Meade and the AP did resolve Antares. Yet -- because of the lateral dispersion, as far as I could tell -- the Meade did not do as well as the AP.

As the evening wore on, the clouds drifted to the east, and it became a fine night. By Moon set, I was ticking off Messier objects in my survey as fast as I could point the telescope. At 44x (Celestron 26 mm Plossl), all the open clusters I looked at were resolved -- and I examined most in Scorpio, Sagittarius, and Scutum. M22 hinted of resolution at that magnification, and at 163x, was well resolved. (A nearby 14.5-inch Newtonian gave a spectacular view of M22, at 107x.) The Omega Nebula, M17, showed much detail, and M16 showed nebulosity as well as stars. I completed my Messier survey with the 5-inch -- that makes 19 -- with M55, pale and difficult even with averted vision, only a few degrees above the southeastern horizon, just after it had risen.

I am looking forward to doing planetary work with the 5-inch Meade, but it will be a few months till the bright planets are well placed at convenient times. Perhaps I will do some Lunar work in the interim.