Yesterday I had a good luck with the club's dark site. My typical experience with the site places it in the Bortle 5 category. The site suffers from a large light dome in the south, and usually some amount of haze is present. When I started my observations around 9 pm, there was noticeable haze, but by 1:30 am the haze cleared. For the first time at this site I could see M31 with just my eyes and M33 was visible in a 8x50 finder. The Milky Way from Cygnus to Perseus was very prominent and detailed.
I performed observations with my 120 mm ED doublet. For star hopping I used Masuyama 85 32 mm (28x, TFOV 3 degrees) and ES82 18 mm (50x, TFOV 1.6 degrees). For detailed observations I used ES82 11 mm (82x), 6.7 mm (134x), and 4.7 mm (191x). I had 2" and 1" 1/4 DGM NPB filters at my disposal.
During the session I observed six planetary nebulae out of six attempted:
- NGC 6781 (Snowglobe Nebula),
- NGC 7009 (Saturn Nebula),
- NGC 6818 (Little Gem Nebula),
- NGC 6572 (Emerald Nebula),
- NGC 6543 (Cat's Eye Nebula),
- NGC 7027 (Magic Carpet or Pink Pillow Nebula).
For each PN I used all five eyepieces listed above with and without a filter. This was my second observation of NGC 7009. I saw NGC 6543 for the second time, but for the first time with my scope (the first observation was last Saturday 8/24 with Rob Teeter's 20" dob). I observed the other four PNs for the first time.
The most difficult observation was of NGC 6781. I did it early in the session when it was hazy. I had to switch eyepieces many times until I finally saw it with averted vision. I confirmed its presence with a filter. The other five nebulae were much brighter. I could see them in the 18 mm eyepiece, and some of then in the 32 mm eyepiece. These PNs stood out from the surrounding stars by their brightness and "fat" appearance.
I observed an interesting phenomenon with NGC 6543 and NGC 7027. I viewed these two later in the session when transparency was excellent. On a short time scale their brightness and apparent size were going up and down, as if they were blinking (I'm talking about direct vision, this has nothing to do with the Blinking Planetary that becomes apparent under averted vision, but disappears under direct vision). At the same time all regular stars remained perfectly still. One look at the star field, and you know which one is a planetary.
Edited by IMB, 30 August 2019 - 12:45 PM.