#1  
Old 06-01-2008, 10:14 PM
kljucd1's Avatar
kljucd1 (Daniel)
Registered User

kljucd1 is offline
 
Join Date: Sep 2007
Location: Gledswood Hills, Australia
Posts: 276
Prime Focus Astrophotography

Hi,

If you want to use an 8" newt for astrophotography, without a barlow, is that where you need to shorten the length of the tube?

So far I have managed to use a barlow and or eyepiece projection to image the Moon without lopping off the end of my telescope, but have not been able to bring it to focus without using this method. I would like to be able to image the whole Moon, rather than the sections I have managed so far.

Let me know

Thanks

Daniel...
Reply With Quote
  #2  
Old 07-01-2008, 04:59 AM
iceman's Avatar
iceman (Mike)
Sir Post a Lot!

iceman is offline
 
Join Date: Sep 2004
Location: Gosford, NSW, Australia
Posts: 36,760
Hi Daniel.

What camera are you using?

If it's a DSLR, or even a DMK, then it's likely you'll need to move the mirror up the tube or get a very low profile focuser.
Reply With Quote
  #3  
Old 07-01-2008, 08:26 AM
bonox
Registered User

bonox is offline
 
Join Date: Oct 2005
Location: Sydney
Posts: 57
isn't the moon a little large for an 8" newt if you want the whole disk in one frame? You wouldn't prefer to piggyback the camera on the tube/mount?
Reply With Quote
  #4  
Old 07-01-2008, 12:24 PM
kljucd1's Avatar
kljucd1 (Daniel)
Registered User

kljucd1 is offline
 
Join Date: Sep 2007
Location: Gledswood Hills, Australia
Posts: 276
Hi,

Yeah Iceman I have a Pentax *ist DS.

I can get something like the following with a barlow, so I am not sure what that would mean for getting the entire moon in the FOV.

http://farm3.static.flickr.com/2257/...37e0a1b6_o.jpg

Oh well, it looks like it might be choppin time , poor thing.

Daniel...
Reply With Quote
  #5  
Old 07-01-2008, 12:27 PM
bonox
Registered User

bonox is offline
 
Join Date: Oct 2005
Location: Sydney
Posts: 57
you might get lucky. The dslr is a big sensor (well, compared to those using webcams anyway) and raising the mirror will reduce the focal length a bit. Your image above shows that you won't get the whole disk with a barlow though and if you need to move the mirror to get focus without it, you aren't exactly spoilt for choice. Good luck and have fun.
Reply With Quote
  #6  
Old 07-01-2008, 01:50 PM
ving's Avatar
ving (David)
~Dust bunny breeder~

ving is offline
 
Join Date: Nov 2004
Location: The town of campbells
Posts: 12,359
prime focus? thanks for the reminder!
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 08:30 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Testar
Advertisement