香港天文論壇

If photographic focal length is not longer than 3000m + seeing is not so stable, don't attempt to take this object.

Taken in 2013 with VC200L + reducer + 100Da @PTC
6x240s @iso800
Autoguided with SX2 mount + 5cm guiding scope + 2x + QHY5 + PHD

Except mirrors, all were made by me. However, the original OTA is still too bulky to be transported to overseas for astronomy. Moreover, the MPCC3 doesn't correct the coma aberration so well. So, I need to rebuild the OTA and tailor make a focuser for installing Vixen's corrector PH and 1.4x extende...

If Vixen VC200L is well collimated, it will be a good killer on imaging small deep sky objects. If the spider structure and tubing design, mainly interior, the bright star will display much beautiful on screen. I will re-construct my VC200L after finishing my 6" F4 travel newt. Single frame taken in...

*** Due to the image can only be viewed after logging in on the sub-page of "TATScope", I repost this thread on this sub-page. Moderator please delete it on "TATscope" sub-page, if no double posting is allowed. Thank you very much. *** DIY an adapter for the connection between Vixen AP mount and Sta...

DIY an adapter for the connection between Vixen AP mount and Star Book Ten controller so that the AP mount can run goto function for either visual or imaging purpose. Finally had time to test it on last Sat evening, though big gibbous moon still high in the sky. This three objects were imaged with a...

Attempt to see the coma correction of TV paracorr on a 6" F4 Newtonian. Seemed the back focus being not so matched with the original design. L=5x30s, taken with 6" F4 + TV Paracorr + 1600 cooled cmos camera @690mm F4.6 Almost full frame image M57_5x30s_L_Jpeg.jpg and cropped image M57_crop_5x30s_L_J...

After doing 1 star alignment manually, commanded AP mount goto M13. Though not dead center, seems not too bad. M13 made in YL with ED81S + 1600 cooled cmos camera + AP mount + Star Book Ten @624mm F7.7 L = 12x45s @-10C with darks calibrated in DSS Almost full frame image M13_12x45s_L_Jpeg.jpg and cr...

Not a lie that I don't like image processing. Huge amount of raw data has been stored in hard disks for years. Recently, took a practice to process milky way images in PI. However, I still prefer final touch in PS for color twisting. Here is an image taken in 2013 in Australia with Canon 100Da + EF2...

Taken with Vixen Baby VSD + reducer + 100Da @240mm F4.35 12x300s, autoguided with Vixen AP non-goto mount + 4cm guiding scope + QHY5LII-M guide cam + PHD2 For larger size, strongly recommended to click on the link below to take a look. www.william-lt-5.com/Trip-Aus_2019.htm Thanks for your looking. ...

Thanks for your appreciation.

人家有$養鴨鴨，我缺$就只可養水牛！ Vixen有只8" F4 (R200SS) 和牛，質素很高，但帶去旅攝，有點困難。故改養一只6" F4 水牛，瘦身一輪後，可跟Vixen AP 赤道儀，出走HK。 原本600mm焦距的他，影星團介子等，有感仍力有不足，幸Vixen最近推出了一只 1.4x extender PH，心內大喜。 4月復活節之旅，Vixen Baby VSD (FL55SS)已擔主角，6" F4水牛未能同行，只好等待11月寶島之旅。 數日前，見夜空有雲隙，不理三七廿一，也在YL走家，試試 6"F4 水牛 + 1.4x extender PH + AP mount 組合的效果。 光...

單張曝光180s @iso1600 (Processed in PS without any dark, bias and flat calibrated)

Taken with Vixen Baby Q (FL55SS) + SD reducer + modified M6 @245mm F4.5 in Rockhampton
Autoguiding: Vixen AP mount + 4cm guiding scope + QHY5LII-MM

昨晚天氣其實是頗差的，天空7成區域有雲，但因快南下，所以也要進行測試 Vixen AP mount 行 goto 功熊 + automated image capture with SGPro。 原本想測試不做任何 star alignment，用 "秘技二" 促成 AP mount 直接 go to 去 M67 + platesolve 開始所編定的 automated image capture sequence。可是北極星天區一直被雲遮擋，北極星不能看見，不能用極軸望遠鏡準確對極。沒辦法，唯有用 "秘技三" 用小犬座主星 Procyron 來對極，需不能很準確，但估計對極誤差是小於1度。...

影M51的季節又到了，希望可以用新的攝影流程方法和新系統試試拍攝效果

單張曝光 240s @iso800 @PTC
Taken with Vixen VC200L + reducer + unmodified 6D @1280mm F6.4
Autoguided with Vixen SX2 mount + 5cm guiding scope + Lodestar X2 + PHD