秋夜的星空冒險/Pentax O-GPS1‘s Setup

天氣很好，但陽明山上氣溫還是一樣很冷，雨衣都拿來穿還嫌不夠XD
快樂的野餐中

加州星雲 (California nebula) NGC1499
RA 04h 03m 18.00s
Dec  +36° 25′ 18.0"
145'x40'
Pentax K5 + O-GPS1,LPS-P2 filter
fl=200mm,ISO3200,F2.8,120s

flatAidePro corrected (2019)


英仙座裡的加州星雲，據說因為形狀與加州相似而得名，老實說我對加州長得怎樣沒有什麼概念，我只知道網購時一不小心買到加州的東西就會被扣很重的州稅 XD
NASA的JPL噴射推進實驗室好像也在加州，以及有首好聽的老歌叫'It Never Rains In Southern California'

http://www.youtube.com/watch?v=-pyC7WnvLT4

火焰星雲NGC2024(30'x30')，馬頭星雲(Horsehead, 6'x4')，以及獵戶座M42大星雲(85'x60')M42
RA 05h 35m 17.3s
Dec -05° 23′ 28″
ISO3200 F2.8 80s
FlatAidePro  corrected (2019)

金牛座的M45 七姐妹星團

RA 3h 47m 24s

Dec +24° 7′
120'
ISO1600,F2.8,60s

英仙座的M33漩窩星系 Triangulum Galaxy  (下圖為裁切過)
RA 01h 33m 50.02s
Dec +30° 39′ 36.7″
68.7'x41.6'
ISO1600,F2.8,90s

加了尋星鏡非常實用（應該說如果沒有尋星鏡會事倍功半，找暗天體仿佛瞎子摸象一般），再加上搭配可以顯示（模擬）尋星鏡及相機視野框線的SkySafari+（見夏夜的星空冒險），用傳統的牽星法找天體特別好用，可以享受手動尋找天體的樂趣。

收藏的國際光器的袋子終於有適合的用途了（本來要裝P75，不過P75另有袋子裝了），仿佛它的存在就是等這一刻到來XD 腳架、雲台及雲台板都可以裝在這個袋子裡剛好，還有點空間可以塞小東西。

＊有三向微調的manfrotto 410雲台用來找天體時非常好用（光用微調來移動就夠快速了。） ，又穩。

＊快速確認及調整構圖的方法：先用ISO51200固定攝影曝光約5~10秒左右（對太暗的天體無效）。

今天上半夜的時候看見一顆超級漂亮的綠色火流星劃過半個天空（那時Eric剛好在小睡^^;），可惜我仍舊本能地只會喊:「哇！」XD

＊以後要多帶衣服，帶保溫杯裝熱水。

＊關於星圖 （原理與用法請參考星圖與使用此篇）

使用Pentax O-GPS1搭配攝影腳架拍深空天體時，因為必須使用人工捜尋天體，對於某些比較暗或小的天體來說依頼對照星圖以參考星漸次逼近（牽星法）是比較容易的方法，所以星圖是必備的。

如果沒有電子星圖也可以使用一般紙本的星圖，最好能有標示出參考星的finder chart（但此類星圖只適合找該星圖有收錄的天體，因星圖並不涵蓋整個天空）,並有關於目標天體的座標（因為O-GPS1曝光時間極限會根據拍攝目標所在的赤緯而不同，所以依赤緯可估算以O-GPS1拍攝大約可用的曝光時間極限，及考慮精度下恰當的曝光時間），亮度，視直徑（可用來大概估計適合的焦長，使用的鏡頭是否有足夠解析力，可以先拍M31當做焦長構圖參考，並利用其旁邊的M32來了解該鏡頭大概能拍到多小的視直徑）等參考資料。

蔡章獻《星雲.星團指南》（圖左）及 E. Karkischka 《The Observer's Sky Atlas》

根據這幾次的經驗，以下個人整理了43個deep sky天體（順序按RA恆星時排列），亮度多在+5~+10之間，且其中有40個objects視大小至少有一方向是在20'以上的，這些是我覺得以O-GPS1和200mm/2.8可以嘗試拍的東西，其實算是不少了，雖然拍起來比較小，但樂趣不減。

＊將手對準星空伸直，小指指尖的寬度大約就是1度的視大小即60'
＊1星等的亮度是6星等的100倍


List: My Favorites 200mm - 43 Objects

List: My Favorites 200mm - 43 Objects
(1)Andromeda Galaxy - M 31
(Spiral Galaxy in Andromeda)
189.1'x61.7'
+3.4
0h43m27.97s
+41˚20'26.1"
(ISO3200,F3.2,60s)
C

(2)Sculptor Galaxy - NGC 253
(Spiral Galaxy in Sculptor)
29'x6.8'
+7.19
0h48m11.68s
-25 ˚12'58.1"
C

(3)Pacman Nebula - NGC 281
(Bright Nebula in Cassiopeia)
35'x30'
+7.4
0h53m35.14s
+56 ˚40'15.4"
B

(4)Pinwheel Galaxy - M 33
(Spiral Galaxy in Triangulum)
68.7'x41.6'
+5.69
1h34m36.73s
+30 ˚43'28.6"
(ISO1600,F2.8,90s)
C

(5)Heart Nebula - IC 1805
(Bright Nebula in Cassiopeia)
60'x60'
+6.5
02h34m25.1s
+61 ˚29'23.1"
(ISO3200,F2.8,120s)
B

(6)Soul Nebula - IC 1848
(Bright Nebula in Cassiopeia)
60'x30'
+6.5
02h52m20.06s
+60 ˚28'09.4"
(ISO3200,F2.8,120s)
B

(7)Pleiades - M 45
(Open Cluster in Taurus)
120'
+1.5
03h47m47.15s
+24 ˚09'19.7"
(ISO1600,F2.8,60s)
C

(8)California Nebula - NGC 1499
(Bright Nebula in Perseus)
145'x40'
+5
04h01m33.95s
+36 ˚39'06.1"
(ISO3200,F2.8,120s)
C

(9)Witch Head nebula - IC 2118
(Bright Nebula in Eridanus)
180'x60'
+10
05h07m32.29s
-07 ˚12'05"
D

(10)Flaming Star Nebula - IC 405
(Bright Nebula in Auriga)
30'x19'
+10
05h17m04.28s
+34 ˚16'44.3"
C

(11)Orion Nebula - M 42
(Bright Nebula in Orion)
85'x60'
+4
05h36m02.8s
-05 ˚26'37.5"
(ISO1600,F4,60s)
D

(12)Horsehead Nebula - B 33
(Dark Nebula in Orion)
6'x4'
*
05h41m33.7s
-02 ˚27'43.8"
(ISO3200,F2.8,80s)
D

(13)Flame Nebula - NGC 2024
(Bright Nebula in Orion)
30x30
+10
05h42m21.9s
-01˚51'44.7"
(ISO3200,F2.8,80s)
D

(14)Barnard's Loop - Sh 2-276
(Bright Nebula in Orion)
600'x30'
+10
05h48m40.77s
+01 ˚00'0.8"
D

(15)Lower's Nebula - Sh 2-261
(Bright Nebula in Orion)
30'x15'
+10
06h09m27.44s
+15 ˚48'44.2"
C

(16)IC 443
(Bright Nebula in Gemini)
50'x40'
+12
06h17m41.82s
+22 ˚46'34.7"
C

(17)Rosette Nebula - NGC 2237
(Bright Nebula in Monoceros)
80'x60'
+5.5
06h31m0s
+05 ˚02'19.5"
(ISO3200,F2.8,120s)
D

(18)Christmas Tree Cluster - NGC 2264
(Open Cluster in Monoceros)
39'
+4.09
06h41m41.47s
+09 ˚52'07.4"
D

(19)Cone Nebula - NGC 2264
(Bright Nebula in Monoceros)
60'x30'
+3.9
06h41m49.47s
+09 ˚52'07.3"
D

(20)Seagull Nebula - IC 2177
(Bright Nebula in Monoceros)
120'x40'
+10
07h05m43.3s
-10 ˚43'19.4"
(ISO4000,F2.8,120s)
D

(21)Bode's Nebulae - M 81
(Spiral Galaxy in Ursa Major)
24.9'x11.5'
+6.9
09h56m36.78s
+69 ˚00'13.1"
B

(22)Eta Carinae Nebula - NGC 3372
(Bright Nebula in Carina)
120'x120'
+1
10h44m19.19s
-59 ˚56'11.1"
B

(23)Lambda Centauri Cluster - IC 2944
(Open Cluster in Centaurus)
65'
+4.5
11h38m57.91s
-63 ˚26'23.1"
B

(24)Running Chicken Nebula - IC 2948
(Bright Nebula in Centaurus)
75'x50'
+4.5
11h39m25.97s
-63 ˚36'23.1"
B

(25)Whale Galaxy - NGC 4631
(Spiral Galaxy in Canes Venatici)
15.2'x2.8'
+9.19
12h42m45.78s
+32 ˚28'11.8"
C

(26)Centaurus A - NGC 5128
(Spiral Galaxy in Centaurus)
25.7x20'
+6.8
13h26m15.79s
-43 ˚05'01.5"
B/C

(27)Messier 101
(Spiral Galaxy in Ursa Major)
28.8'x26.9'
+7.9
14h03m39.88s
+54 ˚17'14.4"
B

(28)Rho Ophiuchi Nebula - IC 4604
(Bright Nebula in Ophiuchus)
60'x25'
+5.09
16h26m23.52s
-23 ˚27'40.2"
C

(29)Cat's Paw Nebula - NGC 6334
(Bright Nebula in Scorpius)
40'x30'
+10
17h21m22.97s
-35 ˚43'39.4"
C

(30)Trifid Nebula - M 20
(Bright Nebula in Sagittarius)
29'x27'
+6.3
18h03m23.94s
-23 ˚01'51.2"
C

(31)Lagoon Nebula - M 8
(Bright Nebula in Sagittarius)
90'x40'
+6
18h04m36.43s
-24 ˚22'49.8"
C

(32)Eagle Nebula - M 16
(Bright Nebula in Serpens)
35'x28'
+6.4
18h19m32.76s
-13 ˚46'32.6"
D

(33)Omega Nebula - M 17
(Bright Nebula in Sagittarius)
46'x37'
+6
18h21m33.54s
-16 ˚10'30.3"
C

(34)Crescent Nebula - NGC 6888
(Bright Nebula in Cygnus)
20'x10'
+7.4
20h12m58.95s
+38 ˚27'28.9"
C

(35)Pelican Nebula - IC 5070
(Bright Nebula in Cygnus)
80x70'
+10
20h19m46.21s
+40 ˚46'35.2"
C

(36)Gamma Cygni Nebula - IC 1318
(Bright Nebula in Cygnus)
40'x20'
+10
20h19m46.21s
+40 ˚46'35.2"
C

(37)Western Veil Nebula - NGC 6960
(Bright Nebula in Cygnus)
70'x6'
+5
20h46m14.78s
+30 ˚45'58.8"
C

(38)Eastern Veil Nebula - NGC 6995
(Bright Nebula in Cygnus)
60'x30'
+5
20h56m56.82s
+31 ˚46'07.6"
C

(39)North America Nebula - NGC 7000
(Bright Nebula in Cygnus)
120'x100'
+4
20h59m16.51s
+44 ˚23'09.5"
B/C
(40)Iris Nebula - NGC 7023
(Bright Nebula in Cepheus)
18'x18'
+7.19
21h01m58.24s
+68 ˚15'11.8"
B
(41)Elephant Trunk - IC 1396
(Bright Nebula in Cepheus)
170'x140'
+5.59
21h39m31.01s
+57 ˚33'38.7"
B

(42)Helix Nebula - NGC 7293
(Planetary Nebula in Aquarius)
14.7'x12'
+7.59
22h30m21.6s
-20 ˚46'09.2"
C

(43)Cave Nebula - C 9
(Bright Nebula in Cepheus)
50'x30'
+7.69
22h57m19.92s
+62 ˚41'15.3"
B

my notes for O-GPS1 (大約推算)
280s--A--230s--B--140s--C--95s--D--80s (Best)
-------------------180s------110s--------------
90 ˚------- 75 ˚------- 45 ˚-------15 ˚------0˚ (+-Dec.)
300s-------------------160s-----------------90s(200mm Limits)

在SkySafari+裡建立這個List，觀測或拍照前叫出相關星圖對於尋找天體非常方便。

PS.

最近看O-GPS1公式網頁發現校正（使用O-GPS1拍攝前必先完成精密校正）的補充事項有些更新：

• * Do not swing or twirl the camera while changing your grip on it.
• * When calibration is unsuccessful, face in a different direction and/or slightly change the angle of grip, then try again.
• * Calibration data is retained even when the O-GPS1's power is turned off.
• * Calibration can be made regardless of GPS signal reception status.

所以更換O-GPS1電池不必重新校正（相機重開機才需要）?不過我個人是更換電池後會重新做一次校正。

(2014/02/11 updated: 根據自己實際使用經驗，只要相機或O-GPS1任ㄧ電源重開，都需重做精密校正，要不然不準。)