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2"starlight focuser

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#1 guanzz

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Posted 22 November 2020 - 11:14 AM

May I ask whether the star point appears to move when this focusing mount is performing star point focusing, especially when the drawtube lip moves back and forth

 

 

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Edited by guanzz, 22 November 2020 - 11:14 AM.


#2 ad701xx

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Posted 22 November 2020 - 06:16 PM

Do you mean does the image shift in the field of view as you focus? If so, no, it doesn't on any of the three Feather Touch Crayfords I own. They are all solid without any play.



#3 guanzz

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Posted 23 November 2020 - 02:16 AM

Do you mean does the image shift in the field of view as you focus? If so, no, it doesn't on any of the three Feather Touch Crayfords I own. They are all solid without any play.

When focusing on the focusing mount I currently use, when the drawtube moves in the reverse direction, the focused bright star will move within a certain range. . . I don’t know if this situation is normal. If the drawtube keeps moving in one direction to focus, the star point will not move.



#4 Jon Isaacs

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Posted 23 November 2020 - 06:34 AM

When focusing on the focusing mount I currently use, when the drawtube moves in the reverse direction, the focused bright star will move within a certain range. . . I don’t know if this situation is normal. If the drawtube keeps moving in one direction to focus, the star point will not move.

What focuser are you currently using?   Crayfords like the Starlight Feathertouch and other normally do not have image shift when focusing.  Some rack and pinion focusers to. Often that can be fixed by adjusting it.

 

Jon



#5 guanzz

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Posted 23 November 2020 - 07:32 AM

What focuser are you currently using?   Crayfords like the Starlight Feathertouch and other normally do not have image shift when focusing.  Some rack and pinion focusers to. Often that can be fixed by adjusting it.

 

Jon

sharpstar 150hnt built-in focuser,how to adjust it?By tightening the adjustment screw?



#6 Gastrol

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Posted 23 November 2020 - 11:13 AM

I have that exact Feathertouch focuser (shorty version) on my SCT.   Racking focuser back and forth, there’s absolutely no image shift.


Edited by Gastrol, 23 November 2020 - 11:16 AM.



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