CWB Rosette Nebula

2 frames mosaic, 1 hour each.

Background a bit uneven, but not mood to have a delicated correction.

Have been sleeping late or haven't slept for consecutive 3 nights...

Orion small-scale Mosaic

Sigh.... I forgot to change the battery when shooting my last frame.

3 frames mosaic

Upper and middle frame: 1min x 60

Lower frame : 1min x 37

I have learnt so much these two weeks shooting from my home in downtown Hong Kong. Although some encouraging results are obtained, more invaluable lessons are taken.

Firstly, I now FULLY appreciate the value of dark and transparent skies. I really couldn't imagine how well these photos can be if they are shot under a dark and clear sky. I compared the photos I took this week and the ones taken indoors last week. The interesting thing is the ones taken last week, despite taken indoors and have much less exposure, are actually clearer, deeper, and more colourful than what was taken this week. This is solely due to the difference in transparency.

Secondly, despite the seemly good results, I actually have less motivation in shooting from my roof (unless the sky is REALLY transparent) after these 2 rounds. It is because I am now very much aware of the limits of this kind of imaging.

Thirdly, I will not use ISO200 on my 350D again...

Finally, the fact that I finished some mosaics despite under these harsh conditions really encourages me to do it in the fields.

2-hour M42 @ CausewayBay

Mosaic of 2 frames, 1min x 60 each.

Centre M42 combined 2 hours of exposure.

In case of good weather...

The weather forecast is quite promising. Tomorrow night and the night after will be pretty clear and I am hoping to expand the urban deepsky shooting project. (A local amateur called me metro deepsky shooting...)

The plan goes like this. There are 3 things that I wanted to do, and I have 3 shooting hours each night.

1) Orion Belt + M42 mosaic. I need 4 frames covering that area, each frame will cost me 1.5 hours, and that will take both nights.

2) Deep 42. Encouraged by the M42 results from last week, I'm confident that If i increase the exposure to 3 hours, the background nebulosity could be brought out. I could just shoot 3 hours for one night or 6 hours for 2

3) Horsehead. Similar to Deep42.

4) Rosette. Similar to Deep 42.

So I could do a 4 pane mosaic, or do 1 or 2 deep shots...

Umm...

Ultimate Urban Astrophotography

After the reasonably good results in the last post, some unreasonable results were achieved a night after.

I combined the data of M42 of 2 nights, a total of 45min of exposure under a mag 3 sky and directly facing the downtown of Hong Kong.

There are still some issues to be solved, like the banding noise and stuff which I've never expected (yet would not happen the next time)

I'm also surprised on how well the horsehead nebula turned out, given an exposure of only 10min under the same sky condition.

M42 indoors

Inspired by a local amateur, also tempted by the excellent weather, I setup my mount and scope at 9pm and decided to wake up at 4am to shoot the M42 this morning, from inside my home window.

Some major stuff to note:

1) I'm glad I'm a guy who can wake up at anytime given a purpose...

2) I spent like half an hour polar aligning, without using a polar scope (shoot indoors), without having a guidescope, super crude drifting method

3) I dare not attempt more than 30sec exposure...

4) After everything is set up and running, I came to the computer and started checking emails, facebook, xanga, typing this blog, you name it...

At this point of writing I may have had around 15min of exposure already

Update01: I'm trying to be the first person shooting the Horsehead nebula from indoors... I'll try that again tmr when I have more time.

Update 02: a total of 23min of exposure was done on the M42...

The result:

ALOHA's M42: Core

The area inside looks pale red compared with the outer area, which leans towards magneta.