How many nudges before declaring your dob collimatable?

[emadmoussa]

OK, yet another Dob question. So apologies in advance.

I'm pretty sure for some members here taking the scope out and squeezing it back into the base is a process that involves some accidental hitting and nudging.

How firmly does the mirror hold collimation? And how do you prevent this accidental ''nudging''?

[RikM]

I have a Skywatcher rather than a GSO but I don't have to 'squeeze' the tube back onto the base. Most times I just move the whole thing in one, base and tube together. If I demount the tube to put it in the car or whatever, the tube just drops back into the base with no effort at all. It barely touches the sides. Once it is sat on the bearings, you just screw on the handles and adjust the tension to your liking. Effortless, which is what a Dob should be

[emadmoussa]

I have a Skywatcher rather than a GSO but I don't have to 'squeeze' the tube back onto the base. Most times I just move the whole thing in one, base and tube together. If I demount the tube to put it in the car or whatever, the tube just drops back into the base with no effort at all. It barely touches the sides. Once it is sat on the bearings, you just screw on the handles and adjust the tension to your liking. Effortless, which is what a Dob should be

It seems to get more flexible the more I demount/mount it, but not even once did I manage to drop it in without the bottom of the tube hitting the inside walls of the base. Probably is about the technique.

[Avocette]

A bit of Dob nomenclature - I think 'nudging' is what you do when you (intentionally) move the Dob to track a target. For me hitting the tube against the base would be 'knocking' not nudging.

Of course the Dob tube is quite heavy but delicate at the same time and inevitably you do knock it a little against the base occasionally. As a result many of us would tend to do a bit of final collimation at the last moment (Barlowed laser works well in the dark).

[Qualia]

I have a truss dob which I lug onto buses, push over scrub lands on a trolly etc, so I guess it might need a little collimation . But to be honest it only takes a second to put everything in its place, even the secondary and it actually becomes a part of the setting up ritual. It becomes quite a pleasure. During the night, especially when viewing planets, I'll have a peek through the Chesire make sure everything is still sweet. My advice is don't worry about collimation; the more you do the easier it gets and more comforting is the piece of mind from doing it.

To get rid of any irrational concern I had for collimation I practiced a little at home in the day light and then one night purposely messed up both mirrors big time and took the truss dob out to the scrub/desert lands. If I didn't get it right there and then in the dark, my evening would have been ruined. With that kind of pressure its surprising what you can do and how trivial becomes the concern over collimation.

[emadmoussa]

A bit of Dob nomenclature - I think 'nudging' is what you do when you (intentionally) move the Dob to track a target. For me hitting the tube against the base would be 'knocking' not nudging.

Of course the Dob tube is quite heavy but delicate at the same time and inevitably you do knock it a little against the base occasionally. As a result many of us would tend to do a bit of final collimation at the last moment (Barlowed laser works well in the dark).

Knocking probably more accurate. But I can always knock the Dob gently to target, can't I.?!

[Moonshane]

you are over-thinking it again. worry not. if you need to collimate it then do, if not then don't. it takes seconds. 

[emadmoussa]

Yep, I tend to over-complicate things...

[baggywrinkle]

Knocking, nudging, tapping; we used to call this percussion engineering in the RN.

[foundaplanet]

Just check the colli once you have dropped it/put it in, it is best to check everytime you use it whether you have given it a gentle tap on the mount or not.

[emadmoussa]

Just check the colli once you have dropped it/put it in, it is best to check everytime you use it whether you have given it a gentle tap on the mount or not.

Now we call it '' colli''...nice But seriously, I've been waiting for my collimator for 10 days now...no sign of it yet.

[Pig]

What are your first impressions Imad ?

[emadmoussa]

What are your first impressions Imad ?

Optically is yet to be tested. I did some daylight testing, and the views are crisp and clear...compared with the C11, there's a very small amount of extra contrast. We'll see how it performs pointed upwards. Monday night is expected to be clear.

The build quality is pretty good. The focuser is very solid yet very smooth. The base is solid and neat and the movement is as light as air...you just nudge the base and it moves. Even my 2-year daughter rotates the scope with one hand...in fact she found  it interesting as a massive size toy that I had difficult time dragging her away from it.

To my surprise, despite its size, the Dobsonian has a smaller footprint than a medium size refractor on an equatorial mount. I just shove it under the staircase and it just blends in with  the background. I never thought I'd describe a Dobsonian as a piece of beauty...but it is. Thankfully the Mrs likes it, which means some freedom of leaving it wherever in the lounge until I've built an observatory in the next century perhaps.

Today I might get a bunch of castor wheels and make a small trolley for the scope to facilitate moving it around the house. Well, you know me...clumsiness is my Christian name!

Having said that, if you never had a 10" reflector you find that there's a level of practice required in order to find your ideal method of transporting it around. It's not particularly heavy, but kind of awkward. I'll see if I can fit some straps or other solution to make life a bit easier.

[Pig]

Excellent,  so all is looking good that's what we like to hear

I have no doubts you will come up with a way to help you move it around, a trolley sounds the simplest and easiest method

[emadmoussa]

I've just noticed you've got the title ''Delos King''....LOL What happened to white dwarf? Crashed under its own gravity?!

[Pig]

I didn't know you could customise it until the other day :-)

You should have one