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moving primary up the tube ?


Guest sharpie78
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Guest sharpie78

Hi Guys,


I am now the proud owner of a SW Quattro 8s and if I attach my DSLR directly to the focuser with the 2" to t-mount adapter I am able to achieve focus without any problem at all.


If I attach it with the 2" to 1.25" adapter so I can use my existing barlow and filters etc I can't get focus. I'm 95% certain that it is due to lack of inward travel on the focuser as the adapter mentioned above brings the DSLR a further 2" (ish) away from the OTA. This is a bit of a pain as I would like to image some smaller objects and obviously want higher magnification than the 30x I get with just the DSLR.


Is my only option to move the primary up the tube or is there another way of doing it ? I had to move the mirror on my little SW explorer 130 so I'm cool with doing the mod but would like to save the grief.


Can any one help please ?


:)


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Guest sharpie78

I found that with my little newt but thought it might be a bit better with the larger scope. Any suggestions on how I might get closer shots of say....the ring nebula or jupiter/saturn ?? Am I just going to have to take images with the magnification I've got then zoom in and crop with Photoshop ?


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I found that with my little newt but thought it might be a bit better with the larger scope. Any suggestions on how I might get closer shots of say....the ring nebula or jupiter/saturn ?? Am I just going to have to take images with the magnification I've got then zoom in and crop with Photoshop ?

Yes, or get yourself an ATIK16ic if you can find one.

Here is a shot of the ring nebula through a Skywatcher 200p (1000mm fl) with an ATIK16ic-

M57_14_29Apr13_ver1_zpse7ee86d3.png

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Guest sharpie78

Thats what I did on my little newt Graham and it worked fine. Think I'll see what results I get as is and then make the decision. 


Seeing as you're here Graham.....I've been meaning to ask you if you do mount servicing ? possibly a belt drive mod for HEQ5 too ? 

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Guest Kheldar

I think you would be disappointed with the results, DSLR's and barlows are not a good mix.

 

Seconded - what's the sense in buying an f4 to use it at f8?!

 

I found that with my little newt but thought it might be a bit better with the larger scope. Any suggestions on how I might get closer shots of say....the ring nebula or jupiter/saturn ?? Am I just going to have to take images with the magnification I've got then zoom in and crop with Photoshop ?

 

Sorry to be blunt, but this is not the correct scope for the job :) Your scope with a DSLR is not designed for close in planetary work. It's a fast Newt. Think big! :D

 

Yes, or get yourself an ATIK16ic if you can find one.

Here is a shot of the ring nebula through a Skywatcher 200p (1000mm fl) with an ATIK16ic-

 

 

This is an equally valid option - smaller sensor, smaller FOV :)

 

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However my advice is this : your scope is an f4 monster, the critical collimation point is about 1.5mm in cross sectional area. Moving the mirror up the tube is firstly going to shrink that ( :ladyshock: ) and secondly make your scope even faster = smaller FOV.

 

Just my 2p, don't do it :)

Edited by Kheldar
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Thats what I did on my little newt Graham and it worked fine. Think I'll see what results I get as is and then make the decision. 

Seeing as you're here Graham.....I've been meaning to ask you if you do mount servicing ? possibly a belt drive mod for HEQ5 too ? 

 

 

The answer is yes to both your questions Jack. :) :) :)

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Guest sharpie78

Thanks for the advice everyone. I know what my plan is now......


  • Leave my new scope well alone......like you say Stephen, what's the point in buying an f4 if I'm not going to use it as intended.
  • Get my focusing spot on and zoom in with photoshop
  • Save for a slower scope to do planetary work with (there goes the plan to save money....never gonna happen in this hobby  :lol: )
  • Use my webcam in my slower little newt if I get the urge to image the solar system while I'm saving up
  • Find something else to tinker with over the weekend now I'm not going to be modding my new scope

Thanks again guys. Once again EMS knowledge to the rescue   :D  :D  :D

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