M16, M22, Moon with D70 DSLR
Since my last report, the days have been windy (gusts up to 30 MPH) and the nights cloudy. But Saturday, 5 June, was clear as sunset approached. I opened the observatory at 1915 MST, 93°F (max in the POD today was 118°F). Wayne Parker at SkyShed POD had suggested that POD owners add a country/state flag to their POD and send him a photo. He wants to show the international usage of the POD on his web site. Above is the photo I contributed, proudly displaying the American and Arizona flags, as well as an Indiana University pennant, in my POD.
1925 MST, just prior to sunset, viewed Venus in 26mm, 9.7mm, and 5.5mm eyepieces. Its phase is getting closer to being “half-moon”. 1930 MST, sunset, viewed Saturn in 26, 15, 9.7, and 5.5mm eyepieces. The view in the 9.7mm (206X) was the best; the rings, ring shadow, and some clouds bands were clearly seen. 2000 MST, could now see four moons of Saturn in 9.7 and 15mm (133X) eyepieces: Titan, Tethys, Dione, and Rhea.
2028 MST, could just see NGC4216, a 10th magnitude elliptical galaxy, in 2” 50mm (40X) and 1.25” 26mm (77X) eyepieces even though the sky was still somewhat bright from twilight. But the viewing wasn’t very good yet.
2045 MST, viewed Omega Centauri globular cluster and Centaurus A galaxy in the 2” 50mm eyepiece. Both objects were almost due south, so highest in the sky from my Arizona site. Nice views. I could see the dark lane in the galaxy with averted vision even though the sky was still experiencing some twilight.
2057 MST, went back to NGC4216 and could now see the elliptical shape of the galaxy in 26mm and 15mm eyepieces. Very nice.
2108-2130 MST, viewed M13, M57, Albireo, and M4 in various eyepieces. Nice views tonight.
I then spent some time viewing the night sky with a 2X nightscope. It provided some fascinating views of constellations and stars, especially those near the horizon. And the rising Milky Way was really nice in the nightscope. Dark lanes were very clearly seen. Of course, this ruined my dark-adapted right eye for awhile.
2215 MST, viewed M20, the Trifid Nebula in 26mm. Still low in the southeast but nice. Lots of details seen. 2230 MST, viewed M22, globular cluster, which was still in some tree branches. Nice and large in 26mm eyepiece. Then viewed M16, the Eagle Nebula, low in the southeast. Could just see some nebulosity.
2250 MST, Milky Way still low in the east but the central portion looked great tonight, with several dark lanes clearly visible to the naked eye. M22 was now clear of the trees and was very nice in 26 and 15mm eyepieces.
2303 MST, began setting up for astrophotography with the D70 DSLR. SYNCed the AutoStar on M16. Attached the camera at prime focus with the Off-Axis Guider and did a focus test using Antares with the Bahtinov Mask. Focus was good, so locked the telescope main mirror into position. Then did a framing test on M16, 2 minutes, ISO 1600, unguided. Satisfied with the framing, I waited until M16 was a little higher in the sky. At midnight, I did a 10 minute, ISO 1600, exposure. During post-processing, I discovered that the focus had shifted somehow. But here is the image, cropped:
Not too bad even if slightly out of focus. But I will re-image it.
I then did 2 and 5 minute, ISO 1600, exposures of M22. I had a challenge finding a good guide star. Here is the 5 minute image, cropped to the same scale as the M16 image:
Focus was even more off. Since the telescope mirror was locked, apparently the focus shifted when I rotated the Off-Axis Guider to locate a guide star in the reticle eyepiece. I’ll have to retake M22 during a future session in the observatory.
0120 MST, sky brightening from the rising waning moon. 0135 MST, took a quick look at M31, the Great Andromeda Galaxy, very low in the northeast, with 26mm eyepiece. Than began waiting for moon to rise above the small hill east of the observatory, which it did at 0153 MST. At 0235 MST, took this image at prime focus, 1/200sec, ISO 1250:
I then did some lunar photography at prime focus + 3X TeleXtender, “hat trick”, ISO 200. Here are two of them:
0250 MST, did some lunar observing along the terminator with 5.5mm (364X) and 9.7mm (206X) eyepieces. The views were tremendous, with lots of relief visible in places.
0303 MST, viewed Jupiter, low in the east, in the 26mm eyepiece through some tree branches. 0310 MST, Jupiter was still in the branches but I was able to view it with the 15mm eyepiece. Three of the Galilean Moons were visible: Ganymede, Europa, and Callisto. Jupiter sure appeared strange with the missing South Equatorial Belt (which recently faded). The North Equatorial Belt was very distinct. Then viewed Uranus and Neptune in the 15mm eyepiece; they appeared as small pale dots, with visible disks.
Closed the observatory at 0330 MST, 73°F. Had a great 8+ hours in the POD.
Sunday, June 6, 2010