Celestron oag/focal reducer help

[rob0971]

Hi, hoping someone can give me a few tips with my set up. Playing around last night with my C9.25, focal reducer, celestron oag, qhy5l II & QHY8L. Managed to get the spacing between the the fr & qhy8l about right with the oag in between but could not get the guide cam to focus. Has anyone with a similar set up got any advice on spacers etc for this set up? I am thinking that the guide cam needs more inwards travel, but if I add a spacer to the main cam, then the fr/cam sensor distance will be wrong? I will be trying to pre focus again this afternoon during daylight.

Cheers

Rob

[rob0971]

Just to add to the above, I do have a crayford focuser on the back of the sct. So it goes, scope-focuser-fr-oag-qhy8l. Don't know if the focuser makes any difference?

[hobsey]

I could be wrong but I think the fr goes in between the scope and focuser.

[rob0971]

I could be wrong but I think the fr goes in between the scope and focuser.

Thanks, but you would never get the correct spacing if that was the case.

[sloz1664]

Hi Rob,

The best bet is to set up during daylight. Make sure you reduce the aperture of your scope to

help with both the QHY's from over exposing.

cheers

Steve

[rob0971]

Thanks Steve. I have now got it sussed. I did a rough set up this afternoon. I did have the spacing wrong as I measured from the wrong point on the focal reducer. After adding another 15mm of spacer, I could then get focus on both cams.

I touched up focus tonight & got the guiding going. I will take a couple of pics tommorow & maybe do a diagram also for anyone else in the same boat.

Cheers

Rob

[kingboya]

Thanks Steve. I have now got it sussed. I did a rough set up this afternoon. I did have the spacing wrong as I measured from the wrong point on the focal reducer. After adding another 15mm of spacer, I could then get focus on both cams.

I touched up focus tonight & got the guiding going. I will take a couple of pics tommorow & maybe do a diagram also for anyone else in the same boat.

Cheers

Rob

I would be interested to see the pics, and the fruits of your labour. Well done.

Sent from my GT-N7100 using Tapatalk 2

[rob0971]

Here's a quick pic of the imaging train on my C9.25

Focuser- celestron f6.3 f/r with sct to 2" nose piece- celestron oag_-15mm T2 spacer- QHY8L cam giving 105mm spacing from rear most part of f/r to cam sensor.

Oag has sct adaptor focuser side & T2 adaptor the other.

QHY5L II is fitted into the the guider focuser approx 15mm from the sensor end.

Distance from centre of the oag to QHY8L sensor = distance from centre of pick off prism to QHY5L II sensor.