Off Axis Guider Focusing

[Gerry Casa Christiana]

5 minutes ago, alacant said:

Just thread a nut until it hits the head of the bolt; instant thumbscrew:)

I suppose once the focus is set on scope and guidecam it shouldn't always need adjusting? Is that your experience? I won't be taking it off. That is unless it doesn't work better than my guide scope!

[alacant]

10 minutes ago, Gerry Casa Christiana said:

Is that your experience?

Yes. The longer m4 bolt is simply to set the position once and prevent it from moving whilst you tighten the other grub screws. Then remove it and thread back the original grub screw. Perhaps best to leave the screw to begin with as you're gonna find focusing with the 120mm by push-pull-tighten a frustrating task and you may not get it right first night. Unlike a wide guidescope, the OAG focus has to be perfect; the abberations are bad enough off axis as it is. Practise by focusing on a distant object in daylight to get you close using sharpcap.

10 minutes ago, Gerry Casa Christiana said:

unless it doesn't work better than my guide scope!

It always works better than a guidescope. Perfect 10 minute light frames every time....

[Richard Thomas]

On 12/07/2018 at 09:43, Gerry Casa Christiana said:

Ah yes mine does have a stalk and I think that's why I think I can't use the focuser because it says with mine it has 26-34mm adjustment on guidecam focusing. Then add 12mm of back focus for my zwo 120mm even if I start with it at the shortest length 26mm + 12mm = 38mm so my helical focuser would need to be under 12mm thick. That's my thinking. Anyway it's arrived yesterday I'll hook it up with the 10mm spacer and see if I can achieve focus. 

Thanks

Gerry

Hi Gerry, have you had chance to try it with the 10mm spacer yet? Could you achieve focus?

I have exactly the same oag and guide cam and the same problem.

Thanks

Rich

[Gerry Casa Christiana]

On 18/08/2018 at 11:42, Richard Thomas said:

Hi Gerry, have you had chance to try it with the 10mm spacer yet? Could you achieve focus?

I have exactly the same oag and guide cam and the same problem.

Thanks

Rich

Yes strange thing was I didn't need the spacer at all so you don't need to get it. 

Gerry

[Gerry Casa Christiana]

On 18/08/2018 at 11:42, Richard Thomas said:

Hi Gerry, have you had chance to try it with the 10mm spacer yet? Could you achieve focus?

I have exactly the same oag and guide cam and the same problem.

Thanks

Rich

Sorry for the delay in replying.