SingAstro

Hi Jiahao, nice photos. I like your photos, especially #1. I saw four planets (Mars, Venus, Saturn and Mercury) and the 3rd-day Moon on 12 August 2010 in Singapore. The sky was clear at that night, I saw Jupiter and Uranus (with binocular) later in the same night. I am glad that I able to see six pl...

Can buy silica gel from photo processing shops or camera shops

guangwei wrote:hmmm not like that.. that time i saw was 10time bigger and it's like a big ring around the moon.

That should be Moon halo, not corona. Moon coronas have smaller diameter than Moon halo.

Is it look like this?
This is call Moon corona. Lunar coronas are produced by high thin clouds.
The Moon was overexposed to show the corona, the spot at upper left corner is Jupiter.

Good photo, sharp and detail.

weixing wrote:Hi,
Then this must be the father of all telephoto lenses and it's a Carl Zesis:
http://www.zeiss.com/c12567a8003b58b9/C ... e100393a1b

Have a nice day.

This lense is very heavy (256 kg), just wonder how to use it outdoor.
Surely, it is very expensive.

Below are the pictures of CBD area before (8.27 pm) and during (8.33 pm) Earth Hour. The CBD area was not darken so much because street lights and annoying bright lights under the bridge not switched off. 33 mm, ISO200, F11, 8s Before Earth Hour (8:27 pm) http://farm4.static.flickr.com/3437/33984962...

Website that describes light pollution survey in Hong Kong conducted by the Department of Physics of the HKU. The organizer hopes that the data collected could serve as references for outdoor lightings regulations by the (HK) government.


Light pollution survey