[matt]

Is it possible to have a telescope perfectly collimated from an optical point of view (checked using a laser collimator and cheshire eyepiece) and still be out of collimation mechanically???

I'm getting eveything nicely lined up in the cheshire and the concentric rings look good in star tests outside focus ... but inside focus is a different story - can hardly see any rings and the white area of the unfocused star is dimmer and less defined???

I'm concerned about the positioning of the secondary.

Thanks