So I'm Frustrated Now

I've been out, set the camera up at IS 200 f2.8 and taken 30, 30 sec exposures. I've followed the instructions for stacking them and all I get is a faint (and VERY noisy) image of the hedge and the stars - it is soooooo far off what I have seen here that I wonder how I will ever get an image that doesn't have so much noise as to make it unusable...Where am I going wrong? Not enough exposures?

I did try one long exposure but that was also a disaster as yet again it was just greyish black noise....

I would really appreciate some help. Thanks

I haven't tried it, but you get to see stars in super dark areas... and away from light pollution.

Could you post some examples? That way we might be able to assess what the problem was a little better.
What was your location? Like Steve said, you really have to be in an area where there is no interfering light.

If you look really really hard there are some faint white dots that are stars - I could see the stars OK - there was some light pollution but there was no moon> When I looked into the sky you could clealry see all of the stars which is why I am frustrated at not being able to capture them I guess...

I'm having some real issues getting the file size down! bear with me...

I can't get the file size down of the stacked photos. PSE wont let me save it as a jpg either, The long exposure is here

http://www.flickr.com …/53228491@N07/4​914839088/

Well looks like you are dealing with a heavy amount of noise in the image maybe as a result of the stacking, which I don't know much about. When I do star shots, I usually have setting of like f/2.0 and ISO 1000 and do 30 second exposures (any longer and I get star trails). With this it seems more like the light pollution really detracted the ability to pick up the stars.

From the EXIF - Aperture f/8.0
ISO Speed 200

You're not doing yourself any favors here. f/8 requires 8 times the light as f/2.8 and you could easily add a couple of stops worth of ISO.
Your starting point should be wide open and a moderately high ISO and then back those settings off if you have reason to do so. ie. You might close down one stop if you know you have a lens problem and you'd probably start at one or ISO settings down from your max. If that's too noisy for you to deal with, then drop down from there.

Steve.

Another thing to try would be to use dark frames. Incorporating these into your processing should help reduce the noise.

What software did you use for stacking? DeepSkyStacker is good. Unless you want star trails, in which case try www.startrails.de

Also, what camera were you using? Some cameras are notorious for long exposure/high ISO noise. If you have to use ISO 200 then you probably aren't going to record much unless you go for 30 second exposures and then, with a standard 50mm lens without a tracking mount, each exposure will have star trails in it, so you won't be able to get deep sky objects or stars that appear as points. To eliminate the trails without a tracked mount, you need to go for a wide angle lens and get more light in, which means a faster lens or a higher ISO, so that you can minimise the shutter speed. If you can use ISO 1600 or above , along with some dark frames, you might get closer to what you are after?

I have the luxury of a full frame DSLR, so a 50mm lens really is a 50mm lens, not a 75mm. I can just about get away with a 28mm lens and 25 second exposures at ISO 800 before trails become a major problem.

PS, with DeepSkyStacker, ALWAYS shoot RAW images. It makes it so much easier

f8? I really thought that I used f2.8 that could explain it...I would try again tonight but it is now about 2 days or rain!

I'm using a 5D with a 24-70 @ 24mm and was taking 30 sec exposures.

I think I need to have another go - check my f no. maybe go somewhere darker and take around 60 x 30 sec exposures and process them in RAW...If this rain ever stops I'll give it a go.

Thanks

Are the single frames clean? Stacking should really reduce noise / increase signal to noise ratio.

Use Deep Sky Stacker, and make sure to shoot darks and bias frames to give you the best noise cancelling. Baz's tutorial is here and read the Deepsky Stacker help file which will tell you how to shoot darks (bascially you put the lens cap on and shoot a bunch of frames at the exact same settings you used to shoot the normal frames) and bias frames.

cheers weatmice . I had fead that one. I think I am going to give it another go tonight - is there much point if the moon is out though?

You are exponsing badly.

First you want to expose as much as possible, the limit depends on your focal length , the area of the sky you are imaging and your personal threshold for star-trails. Increase exposure time as much as you want. That's your expo time.

Once you found your exposure time increase the ISO all you can without blowing highlights, don't go beyond the higher native ISO as that doesn't make sense. In most Canon cameras going beyond 1600 is pointless (except maybe 1D series).

Lens wide open of course.