M45 - The Pleiades Star Cluster (Seven Sisters)

[weixing]

Hi,
Finally, a reasonable clear night on Friday for my Vixen R200SS, Canon 450D and IDAS LPR filter to took their first DSO image...

The high/passing cloud and light pollution cause a big patch of orange "nebulosity" all over those spaces between the stars... try my best to reduce/remove them, but not some "leftover" was still in the image if you look closely (not those on the stars) due to limited skill in image processing... . Will try again when got more free time.

Anyway, I try ISO 400 this time and the result was quite good, but I think ISO 800 might be better.

Below are the settings:
Images: 40 images x 2 minute exposure @ ISO400 (unguided)
Dark frame subtracted and No flat applied.

Have a nice day.

 

[aquilaa]

Nice picture, nice attempt at light polluted sky.

 

[mrericlee]

Where in Spore could you find such clear skies unpolluted by lights?

 

[weixing]

Hi,

Where in Spore could you find such clear skies unpolluted by lights?

The light pollution was there and still very serious even I used a light pollution suppression filter as the image was shot in the middle of HDB flats. ;p I manage to process out most of the light pollution as the "signal" (stars) is still stronger than the light pollution, but some of the nebulosity and some of the image dynamic range was lost during the process.

Anyway, still learning image processing and hopefully I can find some new technique of improving the image.

Have a nice day.

 

[zekai]

cool, something different

 

[redstone]

Do you think its possible to take shots of Andromeda galaxy and nebulae from Singapore?

 

[weixing]

Hi,

Do you think its possible to take shots of Andromeda galaxy and nebulae from Singapore?

Yes, but you'll need a decent tracking mount.

Anyway, now is actually the best time to learn to shoot nebula as one of the brightest nebula and easiest nebula to shoot is now visible.... The Great Orion Nebula (M42) in Orion constellation.

The Orion nebula is very bright and easily visible to naked eye in Singapore. Below was the Orion Nebula I took in 2006 with my previous Canon 300D on a 1000mm F8.3 Achromatic Refractor.

Not good (not even close) compare to my friend image ( http://www.singastro.org/viewtopic.php?t=6676 ) that he took recently... so I'm going to try again when the sky clear up... hope I can took a better image than what I did 2 years ago.

Have a nice day.

 

[wiLLy-LucifeR]

wow! awesome capture.. i nv expect we could catch the orion nebula from local shores. =]

 

[lsisaxon]

Where in Spore could you find such clear skies unpolluted by lights?

Nowhere..

 

[billycadiz]

wow! bringing back my childhood dreams here!!! :lovegrin:

 

[mdzmr]

Really envy your #1 shot.

Unguided= you mean not using the equatorial mount or tracking mount.
How you manage to achieve sharp shot?

I'm just starting to shoot astro. Very new to this. Like to venture more on skydeep

 

[weixing]

Hi,

Unguided= you mean not using the equatorial mount or tracking mount.

Unguided in Astrophotography mean the imaging device is not guided (no feedback loop) to keep the object of interest in a fixed position in the frame. Since there is always some form of mechanical errors in your mount and if there is no means of feedback, star trails will still appear after certain time, so it's still consider "unguided" even you use a motorized or those computerized GOTO equatorial mount.

To do guiding, you need a mean of feedback. Usually this is done by setting up another scope (guide scope) beside and aligned to your imaging device on the same mount. The guide scope will aim at one of the star (guide star) in or beside the field of your object of interest. Any position error appear on the guide star will be feedback to the mount for correction.

How you manage to achieve sharp shot?

Focus carefully and take some test shots to check the focus lor. Live View also help a lot.

Have a nice day.

 

[mdzmr]

Thanks a lot weixing.
Need to do a lot of research and also need to understand those Astrophotography terms.

Ok another noob question. Is it good start for me to use a 1000mm reflex telephoto lens or is it adviseable to mount onto a proper telescopic lens eg. Telescope - Sky-Watcher MC90

I intend to get this telescope for a start.

 

[weixing]

Hi,

Thanks a lot weixing.
Ok another noob question. Is it good start for me to use a 1000mm reflex telephoto lens or is it adviseable to mount onto a proper telescopic lens eg. Telescope - Sky-Watcher MC90

IMHO, it's best to start with focal length less than 800mm... unless your target is the Moon. Also, the longer the focal length the greater the effect of atmospheric turbulence... the image will look soft and not sharp.

For long exposure Astrophotography, the longer the focal length, the higher the requirement for mount quality (less mechanical error) and requirement for accurate polar alignment is higher. Also, guiding may be required if the focal length is too long.

Have a nice day.

 

[wucy24]

Nice works Weixing

 

[mdzmr]

Hi,

IMHO, it's best to start with focal length less than 800mm... unless your target is the Moon. Also, the longer the focal length the greater the effect of atmospheric turbulence... the image will look soft and not sharp.

For long exposure Astrophotography, the longer the focal length, the higher the requirement for mount quality (less mechanical error) and requirement for accurate polar alignment is higher. Also, guiding may be required if the focal length is too long.

Have a nice day.

Ok noted. Thanks a lot for info. Appreciate that.