C9.25 XLT Secondary Position

[Mark in Macc]

Can anyone tell me where the notch on the secondary holder points to on a C9.25 XLT? Are they all aligned in the same direction relative to the focuser? The reason I ask is that I removed my secondary when using a Hotech collimator and when I put it back and screwed the retaining ring on, the secondary holder rotated a small amount. Celestron UK seem to think that it shouldn't be a problem, but it would be good to know if there is a defined position. This is a known problem of Celestron SCTs from what I have read.

[kirkster501]

The notch on mine points to the top.

[Mark in Macc]

Ok, thanks. Is that relative to the dovetail bar?

[Northern Soul man]

Hi Ya Mark, not sure if it really matters, as with the Fastar compatible secondary's they are made to be removed and replaced - so not sure if there is any need to align the housing as the secondary just takes the light cone and sends it down to the focusser through the baffle, and with the nature of the adjustment - you would be able to angle the secondary anyway you want to for collimation - the light reflected off the secondary is adjusted to sort of centralise everything to achieve collimation - due to its design, the secondary sort of floats in its housing and there's no end of adjustment - just so happens that you can get the secondary perfectly positioned to centralise the light cone - not too sure about this but it seems that the design - especially with the Fastars in mind - is so that you can get everything lined up without worrying too much - if its collimated - its fine.

Paul.

[kirkster501]

Ok, thanks. Is that relative to the dovetail bar?

Yes, that's right.  In other words pointing at 12 o'clock wrt the dovetail.