Primary Mirror positon vs Focus Point Question

[RolandKol]

Hi guys,

On my Newtonian 130PDS I can collimate Primary mirror to be closer to Focuser and opposite.

Which direction should I target primary, if I want Focus to be reached with focuser racked our less, if it does any difference at all, but I kinda noticed it does if I am not wrong.

 

[Mandy D]

5 hours ago, RolandKol said:

Hi guys,

On my Newtonian 130PDS I can collimate Primary mirror to be closer to Focuser and opposite.

Which direction should I target primary, if I want Focus to be reached with focuser racked our less, if it does any difference at all, but I kinda noticed it does if I am not wrong.

 

You need to move the mirror further away from the focuser. The distance between the eyepice and mirror is a fixed value about equal to the focal length when when focussed at infinity. So move the mirror down the tube away from the open end.