Hello!! It's Joseph

  月食時間表 月掩天王星: 觀測地點: 清水灣 石澳   HKO space museum Japan live broadcast  google map  Korea  

 There are many useful tools, and various  SPICE kernel is selectable Webgeocalc one of them is: Angular separation  finder Eg: can use this for lunar eclipse. the result is geometrical, not taking into account of earth’s atmosphere and shadow do not have a clear edge On 2022 Nov 8 Moon , earth from observer sun: Minimum at 10:51 UTC solar eclipse 2022 oct 25 11::00:42  UTC  1.03603818

  Han ( aka Immortal30)  250mm F/L 2940mm Yoon http://www.sac-club.co.kr/xe/sp_photo_renew/337285 http://www.gogostar.kr/59/?q=YToyOntzOjEyOiJrZXl3b3JkX3R5cGUiO3M6MzoiYWxsIjtzOjQ6InBhZ2UiO2k6MTE7fQ%3D%3D&bmode=view&idx=4272185&t=board fdk250: http://www.astronet.co.kr/xe/index.php?mid=gallery_dso&menu_srl=61&listStyle=webzine&order_type=desc&category=104001&document_srl=238432 the corrector reducer is 4 elements in 3 groups D=150mm, f=750mm, Flat-field Dall-Kirkham, 유준규님 자작품) https://m.blog.naver.com/PostView.naver?blogId=williology&logNo=221611556984&categoryNo=1&proxyReferer=https:%2F%2Fwww.google.com%2F https://m.blog.naver.com/PostView.naver?blogId=williology&logNo=222251345360&navType=by https://m.blog.naver.com/williology/221878187891 https://m.blog.naver.com/hparksy/169779455 https://m.blog.naver.com/immortal30/220633180895 http://astrophoto.co.kr/astrophoto/239270 http://www.tofrom.kr:90/ex/index.php?mid=rnw&doc

 Kazuhiro Watanabe 渡部一浩 Blog   Sundai gakuen talk  駿台學園 F3mirror  and automatic foucault test

  RASC Roy Bishop  in-the-sky planet ephemerides from in-the-sky 

1959   溫威廉和我（ 馮以浤）同住香港大學聖約翰學院。一晚，威廉跟宿舍一位名叫江景雲的醫科學生閒談時，發現他是天文學大內高手。景雲來自英皇書院。他不但對天文學有高深的認識，還會自製天文望遠鏡。他的望遠鏡長1公尺多些，反射鏡的直徑15公分。這發現使我們大為興奮，決定籌組天文學會，由景雲做主席，威廉當秘書。成立大會於1959年3月一個晚上在主樓地下一個課室舉行。  梅窩宿營。前排左起：鄭肇楨、張振國、游順釗；中排：溫威廉、馬翹生、馮以浤、歐榮生、蔡金源；後排：單澤銘、李作鴻。照片是吳永炘拍的。 廖慶齊在1961至1971年間於皇仁書院任教，並成立全港首個中學天文學會。自1966年，廖先生擔任香港大學校外天文課程導師 1969 中文大學新亞天文學會成立NAAC ( 成立後有數年沒有定期活動) 1971 照片是1971年11月15日,香港業餘天文學會(HKAAU)籌委會的幾位成員, 帶備多枝大小型的天文望遠鏡, 到南丫島遙遠的青年旅舍, 為參加者主講天文講座及教導觀星. 這批天文同好是香港大學校外課程部, 由廖慶齊先生主講的天文班的學員. 他們自己辦了觀星活動, 但沒有天文望遠鏡, 向參加天文班的HKAAU的成員提起, 當然義不容辭鼎力支持. 後來該班的成員, 組成了香港第二個公開天文會社----坐井會. 1971： 香港天文學會 成立 1972： 坐井會 成立 1977: 市政局主辦 自製天文儀 器比賽 1978 市政局康文署舉辦 自制天文望遠鏡班 1980年香港 太空館 10月開幕  1970- 1989 who's who   198x 年 坐井會舉辦天文望遠鏡製作班（關耀平是其中的導師） 2002 星河科研社 不定期辦望遠鏡制作班 2015 港府開始推行 QEF 資助計劃 2019 最後一屆太空館 自制天文望遠鏡班   2020 5月因疫情 太空館臨時關閉 至 21年6月 LCSD history timeline Masterinsight   HkAS   坐井會 2 。 HKMU 本地望遠鏡 天文台位置 1950年代或之後， 香港可見日蝕

 21 Oct, 22   radius 8.4 degrees

Some tips to quick start. Camera Settings Tab : 1: Shoot Mode: Manual Exposure Quality: RAW 2: Drive mode: BRK C 0.3EV 3 ( Cont. Bracket 0.3EV 3 Image) 5: DRO/Auto HDR: Off  6: High ISO NR: low ( Actually dimmed/ not selectable) 8: Auto Slow Shut.: Off Setup Tab : 3: USB connection: PC Remote USB LUN Setting: Multi Sony cameras are picky on USB cable.  Camera will display always " Connecting... USB", no matter which type of USB cable is connected!!!, But not all USB cables work Astroberry INDI: Presets: 1/10 ( or any value less than 1) (indi-3rdparty, indi-gphoto, gphoto-driver.cpp) wait until Expose Indicator turns to  yellow.  minimize control panel. use EKOS as usual.  note: You cannot set the shutter speed to [BULB] in the following situations: When the [Smile Shutter] function is activated. When the [Auto HDR] function is activated. When [Picture Effect] is set to [HDR Painting] or [Rich-tone Mono.]. When the [Multi Frame NR] function is activated. When the [Drive Mode]

        Instructable Isogrid  in aerospace industry  matmatch

spec: Primary mirror: 200 mm, coated 197mm, 1.9 kg， glass thickness 27mm mirror with cell: 2.8 kg primary mirror: focal ratio: f/4 mirror to inner wall 13.5 mm mirror face to back of tube : 50 mm secondary: 63mm nom. (minor axis). Minimum required is 54 mm tube 230 mm outer OTA: 8.5 kg, including lock rings and dovetail, length 730mm nom. as 100% illumination is around 9.3mm, this configuration is mainly for visual. of course won't stop you to go  for astrophoto, with appropriate sizing of secondary, eg 73mm(minor axis)    The mirror has some minor polishing marks at 70% radius, at r =14 cm, width 1 cm i guess those are left behind from figuring it to parabola Slight hill at centre, radius 5 cm coating is a bit opaque, guess it is over 20 years ago. 80 to 85% reflectivity Focuser: JMI 2 inch, with motorfocus , jmi2 secondary holder:   collimation: not easy, but do-able first make alignment by visual, then use the laser collimator. btw it's a test of laser collimator too. the c

  hkas mca(Alan Chu)

    one month after the impact:   JPL SSD lookup  IAU number: 65803 SPK ID: 2065803 MPEC 2020-M83 johnson   archive IAU press release   Minorplanetcenter wiki   asu cas cz   To download data to Stellarium  Cloudynights  NEO links Robotic observation using open source softwares  Observations from A. Nath RASC Toronto 

official website Seeeduino runber , based on GW1N-UV4LQ144 Tang nano 9k , based on Gowin GW1NR-9      Tang Nano 20k Hackaday Discussions  Reddit   Lattice clone ? mat7lab Uwente open source design flow Gow1n-1 LittleBee, Trenz Thelec Lupyeun github , pcbway   ganyunhan github element14 .  Sipeed  Tang Nano series openFPGALoader Gowin notes   PMODs for Sipeed Tang

Mi router 3 pro  spec  R3D with 1TB HDD (SATA) AC2600 NB the USB 3 port is vertical !!! qualcomm IPQ8064 from phoronix linux 6.1 ARM support. Let's see bitswrt linux dts github . beta use as is? IXBT How about full fledged Linux?  Openwrt forum  discussion  Fds   Acwifi   Acwifi 2   right   loven doo github   wireless CAT wiki   smzdm    Initial support in openwrt-xiaomi Seems to be good wifi storage project, or audio server 

The cullinan 22.3045679,114.1623844 the 2 towers are 36 m apart cha guo ling 22.3038328,114.2245805 90.715906°     270.739511°     6409.232 metres https://www.suncalc.org/#/22.3038,114.2246,12/2022.09.17/18:15/1/0 if you want the sun is fully between the 2 towers, the distance has to be 4120 m or less exact location:  22.3050175° N 114.1224029° E  close to this perfect location is kai tak cruise terminal 22.305934, 114.213010 88.32931°     268.348525°     5218.639 metres the towers are ~ 0.4 degrees apart suncalc 22 sep 2022, 18:15    or north point pier  糖水道碼頭 22.29393332408372, 114.20313403140909 Imagejoy 105.658428° 285.67389° 4361.015 metres              ,    suncalc 15 aug, 2022 18:45

photo from Thomas Ku   the UTM coordinates in photo are just for reference  The vertical field of view is ~ 13.5 deg, which is 200mm equivalent for Full Frame camera   wider view: 1. get co-ordinates of east and west tower east tower (Tsing Yi Tower) 22.352942, 114.080527 west tower (Ma Wan Tower) 22.349350, 114.067620 fwd 253.346286°      bck 73.341378°      dist between towers 1387.725 metres height of towers: 206 m distance between towers : 1377 m height of sun at west tower : 152 + (191-152)/2 = 171.5  m height of sun at east tower: 107 + (152-107)/2 = 129.5 m delta h : 42 m atan(42/1377)= 1.747 deg ( 3.5 deg max) where to take photo: loc1: (22.354160, 114.088753) loc2: 22.354442 N 114.086452 E height: (~170m???)  should be around 103 m, to < 148m dist to west tower: (from google map measure tool) Loc1 : 2250 m Loc2: 2014 m     in 2021: loc1: 31 Oct 17:35 next occurrence ( 2 times in a year): loc1: 2 Feb 22 18:05 https://www.suncalc.org/#/22.3494,11

  clinical optics( eg lasik):     astrosurf wiki   simple lab setup:   sunysb edu   rochester   Curvature Wavefront sensing in LSST  Another Curvature WFS article SLAC .  WISH   2 Dr Bhatia SHSlab   COMPASS  simulation  Microlens array   2   Alibaba  

From York Tam post on Facebook: 1. get peak tower info: 淩霄閣 peak tower co-ordinate from google maps: 22.2712357,114.1499638 height: 428 m (389m ?) https://en.wikipedia.org/wiki/Peak_Tower 2. get  approximate photo location distance:  distance from google map: 8300 km approx azimuth is calculated to be ~ 2.94 deg above horizon (top of 2 tower) 3. use mooncalc date and time:  6 Sep 2022 00:56 HKT 4 use this vincenty calculation for more accurate positioning: which gives this location :      22.3104181° N      114.2186257° E (assuming mooncalc 's moon azimuth is correct, convert to its back angle, ie 58.47 degrees) Using planit: so these different approaches have a discrepancy of 100 to 200 metres.(ellipsoid model WGS84 ok?)  suggestions:   -calibration day: do some site survey to verify the co-ordinates, and if location is suitable, a few days or week before. better to have some landmarks for aligning the camera, eg corner of nearby building always have a plan b  bring an equatoria