It is currently Sun May 27, 2018 5:32 pm

All times are UTC




Post new topic Reply to topic  [ 8 posts ] 
Author Message
 Post subject: Andromeda Galaxy
PostPosted: Thu Jul 28, 2011 7:54 pm 
Hi all, I attempted to take some shots of the andromeda galaxy last night and last week using my canon 100d camera. Some shots I tried with the camera on its own with a 50mm lense and some I tried through the c8 telescope last night and to be quite honest ....... not much success.
I am getting better shots just with the camera and the 50mm lense than I am with the telescope, ( think my polar alignment was out ) The astromount seems to help too but just not sure what the best settings are or exposure times etc ....
I have wanted an image of this galaxy since the first time i pointed a camera at the sky and any tips or help would be gratefully accepted ......
Thanks


Top
  
 
 Post subject: Re: Andromeda Galaxy
PostPosted: Sat Jul 30, 2011 7:39 pm 
Offline
Member
User avatar

Joined: Mon Oct 12, 2009 8:27 pm
Posts: 370
Location: Adlington
The Canon with the 50mm lens riding piggy back on the Celestron will be the best way to start. If you can find an old 135mm lens then even better. Because the galaxy is bluish is should record well - the unmodified cameras don't see deep red but with M31 this doesn't matter. Try a range of exposures at ISO400 eg 1 minute, 2 minutes and 4 minutes with the aperture set at F/4 or f/5.6. That should give sharp results. The more exposures the better but I guess you will need a light pollution filter for best results.

Using the Canon on the Celestron with its 2 metre f/10 focal length will be pushing your luck - M31 is also way too big to fit in the field of view. With long focal lengths you will be limited to 30 second exposures anyway but the Celestron is not ideal for M31. A 300-400mm focal length is best for this large object.
Good luck!


Top
 Profile  
 
 Post subject: Re: Andromeda Galaxy
PostPosted: Mon Aug 01, 2011 4:16 pm 
Ok, thanks for that David, will give it a try next clear night. I knew I needed to take as many exposures as possible in order to process them to a good image just wasn't sure which the best settings would be using the canon. Will try out your suggestions and see what I can come up with ...... watch this space !!
Thanks again.


Top
  
 
 Post subject: Re: Andromeda Galaxy
PostPosted: Tue Aug 16, 2011 8:21 pm 
Is there any way I can fit a light pollution filter between my canon and the telescope ?? I know you can easily get ones that fit the eyepiece for the scope but dont know if I can get one to fit the tube that couples camera to scope.......Any ideas ?


Top
  
 
 Post subject: Re: Andromeda Galaxy
PostPosted: Wed Aug 17, 2011 8:34 am 
Offline
Member
User avatar

Joined: Mon Oct 12, 2009 6:47 pm
Posts: 1250
Location: Bolton
dean_kos wrote:
Is there any way I can fit a light pollution filter between my canon and the telescope ?? I know you can easily get ones that fit the eyepiece for the scope but dont know if I can get one to fit the tube that couples camera to scope.......Any ideas ?

If you want to use a filter on a camera lens for taking wide-angle objects (such as M31) then see this post:
http://www.boltonastro.org.uk/Forums/viewtopic.php?f=4&t=7
That filter has a 48mm thread (to fit onto the back of a 2" eyepiece), but if you ask him nicely Brian can make you an adaptor to fit it onto the front of your lens. The one which he made for me is for a 52mm thread, but I have some old "stepping rings" to convert this to 49mm or 55mm for other lenses.

But if you want a filter to screw straight onto the "rear cell" of your SCT, then you should get one like these:
http://www.scsastro.co.uk/catalogue/orion-skyglow-broadband-filter.htm
http://www.scsastro.co.uk/catalogue/orion-ultrablock-narrowband-filter.htm
Just leave it bolted onto the back of your telescope and then you can use it with your camera or eyepiece adaptor.

But if you're imaging with a webcam, then you'll be able to fit a 1.25" filter (broadband or narrowband) in front of its CCD when using it with a telescope adaptor.


Top
 Profile  
 
 Post subject: Re: Andromeda Galaxy
PostPosted: Wed Aug 17, 2011 3:14 pm 
Offline
Member
User avatar

Joined: Mon Oct 12, 2009 6:47 pm
Posts: 1250
Location: Bolton
dean_kos wrote:
Is there any way I can fit a light pollution filter between my canon and the telescope ?? I know you can easily get ones that fit the eyepiece for the scope but dont know if I can get one to fit the tube that couples camera to scope.......Any ideas ?

I've just spotted another product which is a custom LPR filter designed to fit inside a Canon EOS camera body:
http://www.rothervalleyoptics.co.uk/astronomik-cls-light-pollution-eos-clip-filter_d3555.html
so that you can use it with a 'scope or lens, and providing an extra dust-seal for your camera's sensor.
But it's not cheap! :(


Top
 Profile  
 
 Post subject: Re: Andromeda Galaxy
PostPosted: Wed Aug 17, 2011 5:09 pm 
Ok, thanks Ross, I have ordered one for the camera.
Not sure what size I need for the scope though ?? Do I need a 2" or a 1.25" ? I have measured the rear of the telescope and its 1.5" internal.....So is the tube to connect the camera....... The external measures 2" but then with a filter coupled I wouldnt be able to fasten it to scope as the threads would be covered with filter ?? I presume the filter stays on the scope for use with both imaging and observing but not sure where it fits ....


Top
  
 
 Post subject: Re: Andromeda Galaxy
PostPosted: Wed Aug 17, 2011 6:05 pm 
Actually, I have just figured out that there is a specific ones for sct's sorry ...... I presume the camera tube or the star diagonal/eyepiece adapter thread straight onto these ??


Top
  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 8 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group