Falak-Online Komuniti

Assalamualaikum & Salam Sejahtera,

Saya nak berkongsi gambar astro saya yg kedua.  Messier Object 33 - spiral galaxy 3 million light-years away.  Low Surface Brightness object, saya tengok guna telescope pun tak berapa nampak.  Mungkin di dark site senang sikit nampak.  To tell the truth, kalau tgk melalui telescope tak berapa menarik sgt object ni, tapi amat cantik jika dirakam.  The galaxy is right smack in the middle between Hamal and Mirach in the Southwestern sky in the constellation Triangulum.

(http://farm3.static.flickr.com/2258/2138229940_e0ea8c5bcd.jpg)

View Large on Black here (http://www.bighugelabs.com/flickr/onblack.php?id=2138229940&size=large)

Telescope: Nexstar 6SE Alt-Az + 0.63 focal reducer
Camera: Canon 350D unmodded
Software: DSLRFocus to focus and capture, MaxDSLR (trial version) to stack and process, final touches in Lightroom
Total exposures taken: 471 exposures of 15s, 20s, and 25s at ISO1600 (I think 35% was rejected by MaxDSLR during stacking due to trailing) - approximately 1.25 hrs worth of exposure

Single exposure of 15s at ISO1600.  Try and spot where the galaxy is in the below picture. :-).  Thanks for viewing and Happy New Year!

(http://i234.photobucket.com/albums/ee149/rubiyanti/IMG-15s-1600-90090.jpg)

Salam,

 :-o lawa gambar tu! Imagine begitu banyak potential dan posibility sebuah kamera DSLR dengan teleskop sebesar 6" !! Keep it up!  Tak de yang size besar ke?

 :mrgreen:

Salam,

Nice image...at least by small telescope and DSLR.

Trekking tak berapa accurate sebab itu stacking rejected kerana 'trailing' saiz berbeza.  Apa yang perlu anda buat ialah improvekan trekking accuracy dan gunakan exposure time yang sama bagi semua frame supaya stacking tak rejected.

Is it??? :-o  Tracking tak accurate??  :? oh.....didnt notice it. Very good eye sight. Sifu, Cuba explain more about tracking accuracy dan ceritakan tentang alignment method yang sesuai bagi nsyahron. Kita semua ni nak belajar.......

Sila sifu terangkan. :roll:

Tom

Thanks Shah! 

My mount is single arm Alt-Az, field rotation is a problem.  I thought about buying the Celestron wedge to convert it to equatorial, which at GBP200 is a significant investment, but decided against it when I found out I can't use it in countries below latitude 25o (Malaysia included).  I may try to manually guide the mount using off-axis guider later on to improve tracking and get longer exposures, but again with an Alt-Az mount trailing can never be eliminated. 

Saya tak de experience dengan single arm alt-azm mount.  Saya tak pasti kaedah yg terbaik untuk improve tracking mount jenis ini tapi mungkin anda boleh cuba drift methode utk perbaiki azimuth axis dan gunakan polaris untuk altitude axis.

Ohhh...... Kalau kita berada di tempat semacam Malaysia yang susah nak spot polaris? Silakan sifu kasih tunjuk ajar kaedah yang sesuai.  :?

Regards,

Tommy

Oleh kerana awan sentiasa menyelubungi langit dalam beberapa minggu ni, ada masa lebih utk godek2 sikit gambar ni.  Another version as I discover more about image processing (I still hate image processing!). Comments, tips are more than welcomed.
(http://i234.photobucket.com/albums/ee149/rubiyanti/IMG-XXs-XX0ScaledStretchedLatest_fi.jpg)

Signal tak cukup.  Perlu tambah exposure time.  Cuba ubah DDP dalam maxim dan screen stretch hingga ke minimum dan maksimum.  Save dalam format tiff dan final touch up dlm photoshop.

Memang betul signal tak cukup.  Tgh tunggu awan berarak keluar dari kota London nih utk tambah exposure time (2 minggu lagi kalau ikut ramalan, bahkan mungkin salji turun Khamis ni!).  Tapi walau banyak mana pun exposure time tambah, susah nak compete dgn results from GEM (and it is not my intention to).