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Focus issue with Off-Axis Guider Deluxe and Lodestar X2

Celestron Off-Axis Guider Starlight Xpress Lodestar X2 Guiding Help Needed
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Swit avatar
Swit avatar
Hello, bonjour,

I have the Celestron "Off-Axis Guider Deluxe" optical splitter with a Lodestar X2 camera. I can't focus on a star. I don't see any stars. Does anyone have the same set-up ?
How far should I move the camera sensor back?
In PHD Guiding, should I divide the focal length of the reflector (EDGE HD 9.25) by 2?

J'ai le diviseur optique Celestron " Off-Axis Guider Deluxe" avec une caméra Lodestar X2. Je n'arrive pas à faire la mise au point sur une étoile. Je ne vois aucune étoile. Quelqu'un aurait-il la même configuration ?
A quelle distance dois-je reculer le capteur de la caméra ?
Dans PHD Guiding, dois-je diviser la focale du téléscope (EDGE HD 9.25) par 2 ?

Regards,
Swit
jeffreycymmer avatar
jeffreycymmer avatar
Focus during the day is the quickest.  Point to a distant object.  Focus scope first then the guider.
Niels_L avatar
Niels_L avatar
I found that I had to first focus the main camera and then move the guide camera. In the end I had to move some spacers between the main camera and the OAG with the OAG and telescope. As mentioned, easiest during the day.
Eddie Hunnell avatar
Eddie Hunnell avatar
Put the OAG as far back in the image train as possible except in front of any filter / filter wheel (to prevent loss of light to the guide camera by the filter).  Agree with previous advice.  I would add that I lower my take off mirror as low as I can until I start seeing optical effects on the long edge of the image when taking a flat.
Helpful Concise
Swit avatar
Swit avatar
Thank you all. I'm already focusing with the main camera and I'm going to test the focus during the day tomorrow.
Well Written Respectful
David Light Jr. avatar
David Light Jr. avatar
Focus during the day is the quickest.  Point to a distant object.  Focus scope first then the guider.

I picked a tree about a half mile away during the day. Used the finder scope to center the main scope. (Something large is easier to find in the scope). Focus the main, then focus the oag camera. Use a  very short exposure on a loop for a live image view on each camera. Move the pick prism in, until it just obstructs the main camera view, then back out a little. Been a while, since I’ve set one up, but I believe the distance from the pick prism to the main sensor must be equal to distance from the prism to the guide sensor. Takes some time, but you only have to do it once! Then, every so often tweak the guide camera focus, after focusing the main camera. There’s a setting in Phd2 that looks at guide star HFR in real time for precise focusing. Clear skies!
Helpful
Maurice de Ruijter avatar
Maurice de Ruijter avatar
You need a longer spacer - I habe a picture of my ZWO-Cam (174MM) - the included spacer (an extension tube that comes with the camera an can be screwed to the front) is too short and is not even inside the OAG, so I screwed a second one (an extension) on it. Then it works well smile - have fun!
Swit avatar
Swit avatar
[pre=tw-data-text tw-text-large tw-ta]=Y2IQFcHello,
Thank you all for your contributions and responses. I finally managed to focus during the day.
I haven't done this and it helps a lot, because the adjustment range is very short on the trail camera.
[/pre][pre=tw-data-text tw-text-large tw-ta]=Y2IQFcI had to add a 3cm extension[/pre]