Huge guide star

[Veracocha]

Can anyone help? Just tried guiding with a Meade DSI attached to a 8 x 50 finderscope. My chosen star appears huge, moon like. Tried increasing the distance between the DSI and the objective but still mahoosive. Do I need to increase it further or are there any adjustments in PHD to make a difference.

[Paxo]

Sounds like it's out of focus to me, stars should be pretty small through a finderscope, and increasing the distance will only serve to increase the size. How are you bringing this to focus?

Steve

[Veracocha]

Yes, it's way out of focus but I seem not to have enough travel to bring it into focus. Bern at ModernAstronomy said to use his adaptor to connect each together but stars appear huge. Methinks I need an extender between the DSI and the finder.

[Paxo]

I've never used a finder to guide before so I can't really comment, but there are plenty of people on hear who do, I take it the stars are getting marginally smaller in the amount you are moving it away?

Steve

Edit: which version of the DSI do you have?

[Bizibilder]

How are you focussing the finder?

[Veracocha]

It's a DSI 1. I can't bring it to focus guys, that's my problem. I remove the eyepiece, screw in the Meade via the adaptor and there is no focus. I think I have to increase the FL to bring it to focus perhaps via an extension of some sort.

[Bizibilder]

You focus the finder by turning the object lens (the one on the front) there is a locking ring to undo then the focus is found by turning the whole lens assembly. Once you have focus you re-tighten the locking ring. There should be ample thread but if you have never moved it it may be a bit stiff, especially if any paint has got into the thread.

[Veracocha]

I have been through the entire range of thread and there is just not enough travel still to bring the stars into focus. I will stick a barlow case on the front of the DSI tonight to see if this gets focus.