草山星空: 黃昏月、秋冬銀河、C/2023 H2彗星、女巫頭星雲 (IC2118)

11/17

今日因為想先拍彗星，所以五點左右就上山了，經過巴拉卡的觀景太時看到黃昏的霧靄中的台北盆地的景色很美，便停下來拍了幾張照片。

初五的黃昏月（夕月夜）

秋季銀河與夏季大三角（Samyang 8mm, Pentax K3II ASTROTRACER 120sec）

在拍攝彗星的當下幾位認識的同好也陸續上來了。小觀音山電視台的光明燈整晚一直沒滅，對眼視的話影響會很大，希望這只是暫時，不然美好的鞍部眼視觀星環境恐怕要消失了。（今晚發現該電視台多了兩支電波塔，因為有新的兩盞高聳的橘紅色的警示燈，所以有可能是電台在施工？）

I went up the mountain around 5:00 pm to shoot the H2 comet. As I passed the viewing platform of Balaka, I saw the beautiful view of Taipei Basin in the fog of the dusk, so I stopped to take a few photos.

When shooting the comet, my friends I met also came up one after another. The shooting lasted until about 8:30 pm when the comet sank into the woods in the southwest. Then I continued to accumulate exposure of Sh2-129 for two hours.

In the first half of the night, the autumn Milky Way stretched across the northern night sky, and the summer triangle gradually disappeared behind Mount Datun.

Tonight, I brought instant noodles for dinner for the first time. This beef vermicelli is pretty good.

The transparency tonight is quite good. The orange-yellow starlight of several supergiants is clear and dazzling. The winter Milky Way is faintly visible to the naked eye. At around 2:30 am in the morning, the winter triangle hangs high in the south, and the Milky Way cuts through it. It extends from the southeast horizon to the zenith, passing through the other peak of the large ellipse, the Capella in the constellation Auriga , to the northwest horizon.

In the cold, I exposed the Witch Head, which is next to Betelgeuse in the constellation Orion, for two hours. It is equipped with an L3 IR cut filter (even if you shoot continuous light objects in the Anbu, you don't need to add a light pollution filter). This target is expected to accumulate ten hours to improve the signal-to-noise ratio. Although there were occasional gusts of wind, the guiding for two hours was still stable.

While shooting deep sky object with a telescope, I also used a Samyang 8mm fisheye lens with ASTROTRACER to expose the winter Milky Way and the winter triangle for two minutes (at aperture F6.5. to me This lens can only be used at an aperture smaller than F6.5 . The large aperture has serious optical aberration. next time I will try Pentax's 10-17 ).

The lowest temperature tonight was around 7 degrees Celsius, which was super cold. I went home to hide in the quilt at 3:00 am.

冬季大三角與冬季大橢圓 (120sec 2frames , Registar）。下回計畫使用10-17mm 拍攝三張結合，各曝個10~12分鐘左右。

約六點半至八點間的C/2023 H2彗星，亮度已降至約八等。 (Pentax 75sdhf, smc 0.72x, L3 filter, K5 full spectra mod., Takahashi EM-2z guiding mod. MEGENII autoguiding 30secx150, stacked and cropped )

因為它跑的速度相當快，視速度每分鐘約十角秒，因此單張只曝30秒，共曝約75分鐘。