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Connect 2" prime focus adapter to telescope - What do I need

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#1 gpsfool

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Posted 21 March 2019 - 01:01 PM

New to all this - Aspiring Astrophotographer here - working on getting things setup.

 

I have the camera - A full frame Pentax

I have a True-2 Ultrawide true 2" prime focus adapter for the camera - it attaches to the body of the camera fine. This adapter has an outside diameter of 2"; it also has threads on the inside.  I chose this as it is believed smaller t-ring would increase vignetting? 

I have a Explorer Scientific ED102CF with a 2" focuser & star diagonal. 

EQ6r Pro coming shortly - I'm sure I have plenty of other questions on that - for another time.

 

For now my question is - what do I need to connect the True-2 adapter to the telescope?  it's OD is 2 inches - it will slide into the focuser or diagonal of the telescope just fine,  however I need to increase the (is it called back focus?) distance from back of the telescope to camera so as to be able to reach focus within the camera.

 

I have 2' extender tubes which will screw into the focuser or star diagonal but their inside diameter (ID) is 2 inches - thus they slide over my 2" OD True-2 adapter.  

 

I expect there is some adapter to screw into the 2" extender tubes on one side and screw into the true-2 prime focus adapter on the other and you guys will say "...sure you just need a....  "

 

Regards,

Gpsfool

 

 



#2 gpsfool

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Posted 21 March 2019 - 01:17 PM

Ok guys - such a noob - I think I figured it out. 

 

One the back of the focuser is a assembly it's screwed into the back of the focuser - not sure what you call it. A diagonal is inserted into this assembly and snugged down with the thumbscrews. Anyway, this assembly unscrews from the back of the focuser.  With this off of the focuser my 2" extender tubes thread into the back of the focuser, and the assembly i unscrewed form the back of the focuser now screws into the other end of the 2" extender tubes.   The 2True adapter for the camera will now insert into that assembly. Presto! 

 

ugh - noobism. 

 

Regards,

Gpsfool. 



#3 bridgman

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Posted 21 March 2019 - 10:14 PM

Glad you got it working.

 

I'm guessing a bit, but based on your description I think the most common name for that assembly is a "visual back". Basically an eyepiece holder.


Edited by bridgman, 21 March 2019 - 10:15 PM.



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