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Old 10-01-2009, 08:19 PM
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lesbehrens (Les)
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Exclamation Help - how can i get a focus?

hi. i cant get a focus with my Dslr on my telelscope. its nearly there but a little more it would be great. i think i moved my mirror up to get a better focus i also bourght a low profile focuser. i really dont want to cut my tube up. can i do anything else?
thanks
les

Last edited by lesbehrens; 10-01-2009 at 08:48 PM. Reason: spelling
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Old 10-01-2009, 08:39 PM
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If your camera is right up against the focuser, then get a low profile focuser.
Other ways are to have a lower profile T adapter to your focuser, or move your mirror up a little more.

Theo
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Old 17-01-2009, 06:37 PM
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lesbehrens (Les)
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i have tried all these options. it is just a hair off. is there no other way to get a focus with out chopping the tube?
can we move the mirror up farther by putting longer bolts in to push it up??
what can a ccd camera do. do i need to mod the scope?
les

Quote:
Originally Posted by Gama View Post
If your camera is right up against the focuser, then get a low profile focuser.
Other ways are to have a lower profile T adapter to your focuser, or move your mirror up a little more.

Theo

Last edited by lesbehrens; 17-01-2009 at 07:30 PM. Reason: adding
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Old 18-01-2009, 12:19 PM
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lesbehrens (Les)
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t ring

hi. can we buy a low profile t ring or canon eos? i am about 5mm out of focus. this would help. i do not want to chop my tube so other suggestions welcome.
thanks
les
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Old 18-01-2009, 12:22 PM
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Long bolts and springs or Universal Paracorr will both work.
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Old 18-01-2009, 12:54 PM
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A while back when I had an MN76, it lacked a little bit of "in-focus". I solved this by using longer primary collimation bolts etc. plus I cheated a little with the T ring. Take a look at your T ring, and see what the very outside diameter is. If you are brave, get it "spun" down in a lathe to 2" OD, or the same size as your 2" to T ring adaptor. This will allow the camera body to fit into the focuser, up to the very lens flange. If I guess correct, it will buy you about 5 - 8mm.
Gary
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Old 26-01-2009, 09:21 AM
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lesbehrens (Les)
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hi. i got focus in my camera. i used longer bolts to rise the mirror up. wow. now i just need clear skies.
les
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Old 28-01-2009, 08:50 PM
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Congratulations Les.
You were really sweating on this problem. Glad you solved it.
Come on the clear skies.
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Old 31-01-2009, 05:17 PM
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Quote:
Originally Posted by jjjnettie View Post
Congratulations Les.
You were really sweating on this problem. Glad you solved it.
Come on the clear skies.

hi. i did get focus on land base object tried last night but way out of focus. ?????? i dont know. well i am going to try another option.
les
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Old 03-02-2009, 07:22 AM
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Les,
How are you going finding focus?
I am going to try and use my 10" dob tonight with my Canon 350 dslr.
So far my webcam does not go to focus and I assume that the dslr will have the same problem.
If you have been able to get to focus could you please let me know how you did it.
Thanks
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Old 05-02-2009, 09:06 PM
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OK,
I went out for a little while tonight to try and use my dslr canon 350 in the 10" dob.
Looking at the moon it would not find focus going straight into the scope.
This is what I suspected so yesterday I went out and bought an Eyepieces Project Camera Adapter from bintel for about $40 and joined it to a 2 times barlow and there it was. At last I could reach focus on the dslr and the view was great. I was focusing through the view finder on the camera.
The adaptor allows an ep to be dropped into it so I added a 20mm and it looked great. So I suppose this meant that the 20mm was really a 10mm with the barlow.
I then tried a 10mm but could not get the focus right. I am sure that it is there but it is quite windy tonight and maybe the conditions were against me at the higher power.
Now I have photos of the moon with my 10" dob. Only single shots but hey that's a start.
I get the feeling that I may be able to rig something up with the webcam through the adapter. This will be for another night as I have to go to work in the morning.
Hope this helps any one that wants to image with a dslr and a dob.
Thanks
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Old 08-02-2009, 08:25 PM
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lesbehrens (Les)
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Quote:
Originally Posted by telecasterguru View Post
OK,
I went out for a little while tonight to try and use my dslr canon 350 in the 10" dob.
Looking at the moon it would not find focus going straight into the scope.
This is what I suspected so yesterday I went out and bought an Eyepieces Project Camera Adapter from bintel for about $40 and joined it to a 2 times barlow and there it was. At last I could reach focus on the dslr and the view was great. I was focusing through the view finder on the camera.
The adaptor allows an ep to be dropped into it so I added a 20mm and it looked great. So I suppose this meant that the 20mm was really a 10mm with the barlow.
I then tried a 10mm but could not get the focus right. I am sure that it is there but it is quite windy tonight and maybe the conditions were against me at the higher power.
Now I have photos of the moon with my 10" dob. Only single shots but hey that's a start.
I get the feeling that I may be able to rig something up with the webcam through the adapter. This will be for another night as I have to go to work in the morning.
Hope this helps any one that wants to image with a dslr and a dob.
Thanks
hi. that was a good idear. i tried it out too. can u use something like a barlow to give u a focus but be able to get a wider field?
les
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Old 08-02-2009, 08:26 PM
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lesbehrens (Les)
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Quote:
Originally Posted by peter_4059 View Post
Long bolts and springs or Universal Paracorr will both work.

hi how does a universal paracorr work? how will this help?what about a Focal Reducer 0.5x . would this help ?if i add it to the barlow??
les

Last edited by lesbehrens; 08-02-2009 at 08:59 PM.
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