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 Post subject: Imaging the moon ........ Help!!
PostPosted: Thu Nov 05, 2009 10:28 am 
Hi all.....
I have been taking many pictures of the moon with my olympus film camera and some have been coming out ok .... some with some detail in different colours but......... Even though i can get the moon quite large in the zoom lense I cant seem to pick up any detail, craters etc. I have noticed as I have learned with the telescope that I can only really see this detail when the moon has the terminator shadow(think thats what its called forgive me if I'm wrong) so only really try to take pictures of it when this is present....
Could it be that the exposure times are not long enough or do I need some sort of special moon filter on the camera to pick out this detail??
Any help would be gratefully accepted.
Thanks
Dean.


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 Post subject: Re: Imaging the moon ........ Help!!
PostPosted: Thu Nov 05, 2009 12:02 pm 
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Joined: Mon Oct 12, 2009 8:27 pm
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Location: Adlington
Dean,
To get detail on the Moon you really need to use a telescope (prime focus). With 35mm film a focal length of around 1250 to 2000mm will give a good scale. A zoom lens will not reach that nor deliver the quality - which it what you seem to be finding. A moon filter will only make it worse as there will be less light.

Another problem you could be suffering from is mirror slap - as the mirror goes up it vibrates the camera during the exposure. This is normally only an issue with longer focal lengths. If your camera has a mirror-up button try that. The alternatie is to use a black card in front of the lens as a shutter - we all did that in the (distant) past!

Hope this helps,
David


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 Post subject: Re: Imaging the moon ........ Help!!
PostPosted: Thu Nov 05, 2009 4:05 pm 
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Location: Bolton
A friend of mine also found these problems with mechanical vibrations from the camera mirror (on his Canon 40D).
Even though though he was sure that he'd got his 'scope perfectly focussed, the images always came out a little blurry. But now he's realised the source of the problem, he locks his mirror up and gets perfectly sharp images.

Of course a webcam/telescope combination is good for imaging at high magnification, but the size of the CCD is too small to capture the whole moon in at good resolution. So one solution is to take a mosaic of images, and then "stitch" them together into a larger composite picture.
We've got a couple of examples of this technique from our late lamented friend Ste Fielding in the Gallery:
http://www.boltonastro.org.uk/Gallery/thumbnails.php?album=11


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