New 200PDS

[Roy@Aldermaston]

The 200 PDS has just arrived and I've spent a little aligning the finder scope and checking the collimation. There is just one small query that someone may be able to help with. The primary mirror has an alignment ring in the centre, I assume to help with collimation. When I look through the 28 mm eyepiece I can see an out of focus image of the ring, which changes as I rack the focuser, but won't come into sharp focus. My question is, does this indicate that the scope needs collimation? I can see all three primary mirror clips, but the secondary is slightly off alignment with the centre of the primary.

Any help would be appreciated.

Roy

[Adamski]

hello,

If you go to astrobabies web site they have a very good section on collimation, even collimating with a plastic film case which i have found very helpful and accurate and cheap. It explains every aspect of collimation and it will only take you about 15 minutes first time and subsequently shorter after initial collimation.

Good luck

Adamski

[Roy@Aldermaston]

Thanks for that,

I have printed out the guide, but I realy wanted to know if what I dEscribed was an indication that the scope was out of collimation and not a sign of some other problem.

Roy

[Viv]

Here's the link

http://www.astro-baby.com/

[NGC 1502]

The primary mirror has an alignment ring in the centre, I assume to help with collimation. When I look through the 28 mm eyepiece I can see an out of focus image of the ring

Hi Roy. With an eyepiece in the focuser, it's not possible to see

the ring in the centre of the mirror. It can be seen if the eyepiece

is removed. The ring doesn't have to be in focus to use it for

collimating, as long as you can see it.

Regards, Ed.

[Roy@Aldermaston]

Thanks Ed,

I thought it was an out of focus image of the ring that I could see, but obviously not. The effect is like blurred patch in the centre of the FOV when looking through the eyepiece. I have only had the scope for a few hours and focussed it on distant trees, but the effect is there - I should say that I haven't tried another eyepiece yet. As I explained I have a copy of Astrobaby's collimation guide, but I didn't want to dive into collimation if the problem lay elsewhere. Predictably the skies have cloudy over, but I'll have a look tomorrow and see if I can sort it out.

Roy

[crowlord]

Dont worry Roy, you are seeing the secondary mirror. For some reason you can during the day! In normal use you wont see it at all.

Clear skies

[Roy@Aldermaston]

Thanks Crowlord, that's brilliant.

I didn't think it was a collimation error and I didn't want start collimating the scope unnecessarily, but I have Astrobaby's great guide ready for use when needed.

Thanks again,

Roy

[valleyman]

With a Fast scope like the 200pds you will notice that the alignment of the Primer is off center and this is normal....Astrobabys tuturial explains this

[Roy@Aldermaston]

Thanks for all the help. This my second scope and I'm looking forwards to seeing how it compares with my 4 inch Mak. I stretched the budget as far as it would go and bought an NEQ6 mount, with the intention of doing some serious photography - great service from FLO for the tube and mount.

Roy