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edge 11 at f7 or f10 focusing issue (after hyperstar)

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#1 markm75c

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Posted 08 January 2020 - 10:04 PM

I'm suspecting i goofed in replacing the secondary mirror after having the scope at f2 for months.

 

At this point with the asi294mc pro and either f7 or directly at f10, i cant achieve focus (nstep focuser).  I've tried both ends of the spectrum with the focuser (1 to 36,000) and aiming at the moon and in sharpcap (low ms exposure), i cant hit focus (also have the efw wheel in play that i had with the hyperstar).

 

Would goofing the secondary "index"/ original placement cause this much of a focus issue?

What would be the easiest way to correct this or find the original spot if that is whats going on here?

 

Any thoughts?

Thanks in advance



#2 james7ca

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Posted 08 January 2020 - 10:41 PM

My only guess would be that the secondary mirror isn't seated properly to the corrector plate. Are you sure that the secondary mirror is completely flush to the corrector plate and that the retaining ring is properly threaded?

 

Also, I assume that you've checked the collimation.



#3 markm75c

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Posted 08 January 2020 - 11:02 PM

My only guess would be that the secondary mirror isn't seated properly to the corrector plate. Are you sure that the secondary mirror is completely flush to the corrector plate and that the retaining ring is properly threaded?

 

Also, I assume that you've checked the collimation.

I'm pretty sure it is, just maybe not the same position it was as before.

 

I cant check collimation because i cant get focus.  I was using the moon to try to establish any kind of focus and it only slightly shrunk down when i worked the nstep from end to end.



#4 markm75c

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Posted 09 January 2020 - 01:27 AM

I was able to correct things.  I took the nstep off the knob, turned the knob all the way left till it got tight, the image came into focus finally.  With nstep software it just wasnt changing.  I put it back on and did some fine tuning and now it seems fine.  




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