OMC 140 concerns

[stefski]

Hi All,

I know there are frequent questions re collimation on astro forums, I've answered a fair share. However, I've encountered something with my scope that I've not seen before and am a bit concerned...

I noticed comet tails on stellar images, so thought it was time to sort the collimation out...out came the allen key. I defocused the imaged and noticed the black circle was towards the edge of the donut. No problem, I thought, just got through the usual routine I've done many times before....However, I then noticed that the donut itself was not circular but in fact kidney bean shaped (very pronounced at high mag). I've not mounted another scope on the OTA and I can't see anything pinching the optics. Also, when adjusting the allen bolts for collimation, the image moved (as expected) but the central black spot didn't budge?!

Am quite concerned there is a problem with the primary....

Any ideas?

Stef

[andrew s]

Stef - I think you may be right the primary may have slipped. I would contact John at OO they are always helpful and best placed to help you fix you problem.

Andrew

[stefski]

Oh no....:-(

I'd better give them a call.

Cheers,

Stef