香港天文論壇

Try again on playing HDR in PS. Taken with Vixen AX103S + 0.7x reducer + 100Da @578mm F5.6 in 2003 @PTC Total exposure = 9x480s + 9x60s @iso 800 Autoguided with Vixen SX2 mount Firstly processed in PI with DBE, PCC tools and then final touch in PS for HDR composition and adjustment with Level, Curve...

M42, an object I take every year in Hong Kong and have been imaging for more than 10 years. So, recently I started an attempt to combine all the images taken with different scopes and DSLRs, which I call it as M42 project, to see what the result will come out. That is the first attempt of combining ...

極端天氣已加快頻率出現！去年袋鼠國已多處打破最熱紀錄，今年更再破紀錄中........ 有台灣同好會2月前往中部沙漠看紅石。OMG！！！午間超過50度的氣溫怎樣過？？？ 2016年復活節到過Tennant Creek，日間氣溫超過40度已感很辛苦。超過50度的，真不敢想像了。即使午夜前，氣溫也在30度以上。 單彈曝光240s @iso1250，no dark, bias and flat calibrated Taken with modified 5D2 + EF8-15mm F4L @15mm F4 Unguided with Vixen Polarie 這麼熱，沒有冷凍，熱訊與星星，已熔...

All the RGB data were taken at 3 different nights last year. However, due to the unstable weather conditions with interference of crossing cloud, quality of each sub-frames varied frame by frame. Just want to see what the result would come out, and so didn't use sub-frame selector in PI to select th...

Taken with Vixen Baby Q (FL55SS + HD reducer kit) + 100Da @237mm F4.3
15 x 180s @iso1600, autoguided on comet with Vixen AP non-goto mount
Stacked and processed in PI

究竟46P有尾定無尾呢？

Bad luck to me again. Stayed 3 nights in Taiwan last week but only had about 1 hr of cloudless sky in total for imaging. Taken with Vixen Baby Q + reducer HD kit + 100Da Single shot of 46s @iso1600 Unguided with Vixen AP non-goto mount No dark, bias and flat calibrated Processed in PS Comet_46P_46s....

Conditions were very terrible. Cloud kept flying by and severe light pollution at that spot.

Taken with Vixen VC200L @1800mm F9
L channel only = 5 x 120s, autoguided with Vixen AXJ mount in RA direction only

Stacked and processed in PI with bias and dark calibrated only.

Taken with DIY 6" F4 newtonian + MPCC III + LPS + 100Da @PTC 2 years ago 13x240s @iso400, autoguided with Vixen SX2 mount 600mm焦距 + APS-C sensor 相機，我個人覺得是拍M42、M45、M31、M8.....等等類似大少深空天體特寫照的最佳組合。 個人很喜歡用牛牛(newtonians)拍DSO，並不是因為那些十字光茫，而是因為很少有露水問題。遊擊攝影，特別是到海外攝影，"電" 是一個很大的問題。用發熱帶除露，會用去很多"電"的。另外，牛牛亦沒色差問題。 ...

It was so clear, sunshine, and the sky was so blue in the morning 2 days ago. So, went to PTC to go on gathering the photon of M33. However, bad luck again. I arrived there together with cloud too and then left with much frustration. Tried the correction exposure ratio for each RGB channel but not s...

Is it still worthy for combining L channel data into this RGB M33 ?

Taken with Vixen SD103S + HD reducer kit + 1600 MM-C @624mm F6.1 on Oct 30th
R=G=B=8x180s

Old film image, new processing tool Taken with Vixen DED108SS astrograph + kodak E200 emulsion in 2007, manually guided with Vixen GP mount Preprocessed in PI with DBE, BackgroundNeutralization, ColorCalibration, Histogram, Curve, MLT., and then final touch in PS There should have no noise in a film...

What will be happened when PCC in PI is applied on a film image for calibrating the color of stars?

Any thoughts about PCC could come out ?

Film image taken with E200 emulsion and Vixen DED108SS astrograph in Coonabarabran in 2007.

好揀唔揀，揀著個爛燈盞 (廣東俗語)

原本前晚都可取得 permit 去 PTC，但想多一點拍攝時間，最後選擇昨晚出擊，結果.......

透明度低左
高層雲多左
其後更吹勁風.....

When the light pollution is so severe... the seeing was not so good... the ground kept vibrating.... Moreover the sampling as way over so much.... You might imagine what result would come out !!!!! LRGB image taken with VC200L @ f.l.=1800mm, F9 at my observation site in YL last night @ sampling = 0....

實在有太多data閒置不理，偶然找到就隨意處理

Taken with Vixen 20cm F4 牛牛 + corrector PH @PTC
Ha channel = 5 x 360s