New 10" Dob

[DJVege]

Hey guys,

Just letting you know I got out for a 3 minute view of Mars tonight! Yay! Horrible seeing, and it was between clouds, but I can finally say I've used my 10" Dob!!

However, I think I've been spoilt by my HEQ5! When I've got the Dob pointed at a target, how do I lock it in that position so that I can change EPs without it moving? I changed from my 2" 30mm to my 7mm, and the whole thing moved 20cm!!! Is there some sort of mod I can make to lock the Dob in place? If not, I can see myself buying 10" rings for the HEQ5 very soon.

Doug and Eric, the collimation moves about a mm when moving from horizontal to vertical, however, keep in mind I didn't have the set screws locked. It was more of a rushed collimation in order to get the scope outside before the clouds covered Mars.

I also can't comment on Coma just yet, cause I'm sure the collimation was nudged when I moved the scope outside. However the view is much crisper in my 7mm nagler, than my 30mm 2" Andrews EP.

All in all, love the increase in aperture!!!!!!!!!!!!!!!

[duncan]

Get the rings.
You lucky fella.
I need an EQ mount!!!!!!!!!!!!!!!!!
Cheers,
Duncan

[Phil]

Any photos yet DJ love to see sum mate.
Phil

[erick (Eric)]

Originally Posted by DJVege

...When I've got the Dob pointed at a target, how do I lock it in that position so that I can change EPs without it moving? I changed from my 2" 30mm to my 7mm, and the whole thing moved 20cm!!! Is there some sort of mod I can make to lock the Dob in place? If not, I can see myself buying 10" rings for the HEQ5 very soon....

Change eyepieces?? You should be so excited that the only movement is finderscope <==> eyepiece! I presume you mean it moved in Alt. Have you got the tension springs on? Pull them tighter - don't put the "cloth" loop over the screw - pull the spring over it! Other approach is to balance with weight. Two options:- 1) weights of some sort (lead?) wrapped up and attached with velcro to various places at the top or bottom of the scope. 2) magnets (chopped out of speakers are good) wrapped in a bit of felt. They can be placed anywhere on the tube and fine adjusted to get balance depending on eyepiece weight and elevation. But watch the angle of elevation. As you increase, the magnet can be inclined to slip. A worrying sound is the THUNK as the magnet hits the lip of the mirror cell mount and falls off into the dirt!

Originally Posted by DJVege

...Doug and Eric, the collimation moves about a mm when moving from horizontal to vertical, however, keep in mind I didn't have the set screws locked.....

I never tighten the three "lock" screws when I am in the field, only during transport. That's the way I was shown for my 8" and I guess I've always worried they would push the mirror out of collimation. I must experiment on the 12" - they might prevent that small change I did see??

[DJVege]

LOL! Thanks Duncan!

Phil, sorry, will take some photos tonight and post them here.

Eric, yeah, sorry. I meant the dob moves in altitude to easily when I change EPs. I'm also keen to check if the mirror moves as much when if the set screws are locked in.

My argo navis should arrive in a couple of weeks. Jealous? It's for my HEQ5 though. Yay!

[DJVege]

Hey Phil,

Sorry for the tardiness in getting these photos up. Had a crazy Australia Day weekend on the Goldy!

Anyway, here are the 2 scopes I have now! I think you'll recognise the Intes!