Help me get rid of this noise

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Schmooblidon

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Hey guys, I was attempting to take pictures of the night sky last night and ended up with this: http://i58.photobucket.com/albums/g275/willbeats/DSCF3549.jpg
Theres a weird type of possibly noise, all over it!
I put the shutter speed to 30 seconds, the maximum my camera can do. I have a FUJIFILM FinePix S6500fd. Also i noticed the stars it does pick out are quite blurred, how can i fix that. And one last thing, Ive heard of a bulb mode where you can have a shutter speed as long as you want, does anyone with this camera know how i can enable that?
 
30 secs is a long time and the stars will blur because the Earth has moved. You need a tracking mount to match the speed of the Earth's rotation, not sure how much they are.

Also, your camera is not the greatest so it will create some noise.

There appears to be some light pollution too which will not help.

I hope this helps you a little.
 
having just read the spec on your camera, there isn't a bulb setting. The longest shutter speed you have available is 30 seconds.
What ISO did you use for the shot? The lowr the ISO, the less noise you wll have.
I'm looking at the shot on a **** laptop so not the best way to assess it but the noise doesn't actually look so bad from what I can see.
I am wondering however what it is that you really wanted to capture in the sky...was it simply the night sky??;If so then perhaps to have zoomed in a litttle so as not to have the fence etc and use of a tripod? The world is pinning all the time so even in 30 seconds the star will have moved....I'm some what green when it comes to night sky shots but I'm sure there are others on here who can offer plenty of good advice
 
I think the ISO was on 200. The quality was on 6M N. The photobucket isnt very large so i uploaded a close up here: http://i58.photobucket.com/albums/g275/willbeats/zoomed.jpg
The light pollution your seeing is probably the moon, it was a very bright full moon and was just to the right of the shot. I quite liked the fence in the picture as i kind of shows the gap between where we are and the stars, I will try to mimic the same thing but with trees, if i can sort this out. If 30 seconds make them blur, how could i get a clear picture with a shorter shutter speed?
 
shorter shutter speed with lowlight equates to a higher ISO and wider aperture. The wider aperture possibly being impossible if you shot wide n already and the higher ISO inevitably will give additional noise.
Not the news you want to hear I guess but I think you are very much limited by the gear that you have.
Having said that I suspect you may be able to improve on your original version but as already said, this is not my field so hopefully somebody with more experience will come along and guide you further.
 
Light pollution is from streetlamps etc....

What were you focusing on?....You need to focus to infinity if you are trying to get the stars.....I am not sure if your camera can do that.

You will probably not be able to get a clear picture of the stars with a short shutter speed as they do not throw enough light off for a camera sensor to pick up. The human eye is far more sensitive, that is why we can see the stars.

Like I posted earlier, you need a tracking mount for a tripod and your camera.
 
How did you focus on the stars? Does your camera allow the use of manual focus? Not much you can do about the noise (except possibly something along the lines of noise ninja) but I would be surprised if the focus was correct

Edit: Ah, tom beat me to it.

For a wide angle lens a tracking mount isnt the most important thing as the trails wont be that bad but if you were seriously looking into doing astrophotography it would be a good investment
 
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:O i just found out what AF and MF stand for, i always wondered what that dial was on the side, and why the focusing dial never did anything. Ive learnt a lot today about exposure and focus, so I think I might just try this again the next chance i get. That pic would of been on Auto focus with around F3.8, I hadnt a clue what that meant at the time.
 
we're always glad to help...give it another go and let us know how you go on
 
In that case take your camera out during the day, autofocus on something very far away and then switch it to manual focus. After this DO NOT touch the focus at all and when you take it outside the stars should be much sharper
 
You could probably do quite a bit in post - do you have Photoshop or similar? I'd run it through a noise reducer ( the *free* :) ) community version of Noiseware is excellent), boosting the blacks may help, and sharpening certainly will.
 
wealthysoup said:
In that case take your camera out during the day, autofocus on something very far away and then switch it to manual focus. After this DO NOT touch the focus at all and when you take it outside the stars should be much sharper
Click to expand...

That most likely won't work. Fuji bridge camera MF rings aren't mechanically connected to the focus, it's electronic, and the camera usually resets it when it's turned on (speaking from experience with my S9600).
 
A few thoughts.

That is not a bad photo at all given the circumstances - it is difficult to get good star shots on a moonlit night. The moon is just so much brighter than the stars that it has a huge effect.

If you want good star shots then go for a moonless night and a location as free as possible from light pollution.

Your shot looks like you are already somewhere with little light pollution, so given a clear night with no moon you should get something reasonable, but finding the darkest site possible will help a lot.

To get stars which look like points rather than trails use the 600 rule.

The longest shutter speed (in seconds) you can use before the stars start to form trails = 600 divided by the effective focal length you are using. Effective focal length means the 35mm equivalent. On the S6500 the widest angle of 6.2mm is equivalent to 28mm on a full frame 35mm camera, so the maximum shutter speed is 600/28, ie about 21 seconds.

This is a guide and will be a bit different depending on latitude and what part of the sky you are photographing, but it is a good starting point. As your photo shows 30 seconds still produces good results.

Software can help to bring out a few more stars or you could stack a number of images using something like this - http://deepskystacker.free.fr/english/index.html

Dave
 
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