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Author Topic: Is it possilbe to do astrophotography with a normal digital camera  (Read 7988 times)

Offline halsap21

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Is it possilbe to do astrophotography with a normal digital camera.

Regards Lee


 

Offline daveshorts

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I have no direct experience, but I would have thought you could definiely get some results. I have taked photos down microscopes and telescopes during the day using normal digital cameras, and with my most recent camera (Fuji f30) I have taken photos of stars just looking at the sky, so a digital camera can be almost as sensitive as your eyes. So if you can see something down the telescope you should be able to get some sort of image in a digital camera. You would have to attach the camera to the telesope to minimise wobble as the exposures would be of the order of several seconds so you wouldn't be able to hold the camera.

You are of course limited by the length of exposure your camera can achieve so you probably won't be able to manage the 15min exposures that serious people use. Although you may be able to achieve something similar by taking lots of photos then summing them. Although you would need a remote way of taking the photo as pressing the button would shake the camera too much.
 

another_someone

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It all depends on the type of digital camera, and the type of equipment you have to go with it, and the type of photographs you want to take with it.

As Dave says digital cameras can be very sensitive, but many of the smaller digital cameras can be subject to electronic noise causing problems with the picture.  Larger cameras (such as digital SLR cameras) are generally less prone to noise.  The F30 is one of the best small cameras with regard to limiting the amount of digital noise visible with low light shots, and generally the Fuji range is quite good.

You will want a camera which is camable of very long exposure times (preferably a 'Bulb' setting), and with a dark frame subtraction (which will remove hot spots from long exposure shots), and make sure you use a low ISO setting (this will extend the exposure time, but since you will anyway have to have the camera on a tripod, this will not matter, but the lower ISO setting will reduce digital noise).  Some cameras actually have a scene setting for night time shots.

Additionally, if you have a camera that uses a cable release, or remote control, this will reduce the amount of camera shake you will have from holding the shutter release down.
« Last Edit: 25/04/2007 15:06:12 by another_someone »
 

Offline RD

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Is it possilbe to do astrophotography with a normal digital camera.

It is possible to attach a cheapo webcamera to a telescope...
http://www.astrocam.org/english.htm   
 

Offline halsap21

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Thanks for your replies.
 Regards Lee
 

Offline Soul Surfer

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I use both normal digital cameras and videos and a digital SLR for astronomical photography. 

Basically a simple camera will take a photograph of anything that you can see and if it is a video with a high sensitivity/infra red setting it will do a bit better than that  so objects like the moon, planets and brighter stars and nebulae are OK.

If you want to go further and see faint objects you cannot see with the naked eye and the telescope you will need agood quality camera with a long exposure setting and you should be able to go right down to the limits of the sky in your area.

Amateur astronomers using small telescopes and image stacking techniques are getting better results with digital cameras than the best telescopes in the would did a few years ago  although the hubble and some ground based telescopes are producing fantastic quality nowadays.

The big problems are focussing, holding the telescope steady and tracking the earth's rotation for a long exposure picture with an amateur sized telescope  (say around eight inches)
 

lyner

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The big problems are focussing, holding the telescope steady and tracking the earth's rotation for a long exposure picture with an amateur sized telescope  (say around eight inches)
If your telescope  is good enough to see the impressive astronomical objects it will have an 'equatorial mount', which means, basically,  that it can be set up so that it swivels around an axis parallel to the  North South axis of the Earth.
If you need a long exposure, then you will need a motorised drive to  keep the telescope pointing in the same direction as the earth rotates beneath it. They used to use clockwork drives but now they use electric motors to do this. This sort of thing is readily  available and needn't cost an arm and a leg; certainly not compared with a good scope.
You can take pictures of the moon and planets without all this, just using a 'long' telephoto lens. After all, the Moon is not far away and is in full sunlight.  A short exposure will be enough for some stunning pictures. Automatic metering on a camera may over expose this sort of image grossly so you  may need to do a lot of test exposures to get the right one.
It is not a trivial exercise to get more adventurous pictures, though. As other posts have said, camera shake and movement blurr are significant factors.

 
 

Offline RD

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The big problems are focussing, holding the telescope steady and tracking the earth's rotation for a long exposure picture

For DIY enthusiasts, here is how to build a "Scotch" mount which allegedly will permit a 20 minute exposure with a standard camera lens.
http://www.philharrington.net/scotch.htm
[Don't blame me if you get RSI from hand-cranking the thing  :).]
« Last Edit: 30/04/2007 17:24:38 by RD »
 

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