Returning to Stargazing, Still got SkyWatcher 150p Dob, Need Help

[stokeben]

I’m back on here and back to stargazing. I was a member on here previously under the alias lighty89, but have been locked out from that account!

Anyway, I want to start using my telescope again as I’ve got a 3 year old daughter who is really interested in it as well now.

Ive got a 150p SkyWatcher dobsonian that I want to use again, I had it about 7 years ago and it’s never had any maintenance, so to ensure it’s performing at its best what do you suggest?

Cheap/easy ways preferred.

Thanks in advance.

[MarsG76]

welcome back....

I suggest that make sure that the mirrors are clean and collimated and you're ready to go.

See if you can get your old account unblocked...

 

[cletrac1922]

Would not touch the mirrors, unless have a lot of gunk on them

Collimation should also be fine, if not been bounced around in back seat of car for any reason

I had to clean mirrors on club loan dob, as was returned in cardboard box, which container cockroaches, and had cockroach gunk on primary mirror

All I did, was using a swab of cotton wool, slightly damped in distilled water, wiped over primary mirror, to remove gunk, and wiped over with soft dry micro cloth

No need to remove primary mirror, just reached down inside the tube, as was a flex 10" dob

Did out on the driveway, and sun dried

John

 

[bottletopburly]

6 hours ago, cletrac1922 said:

All I did, was using a swab of cotton wool, slightly damped in distilled water, wiped over primary mirror, to remove gunk, and wiped over with soft dry micro cloth

Never clean your mirrors this way 

[stokeben]

How would I go about collimation? Not exactly sure what it is. I think I may need to do it though as we've moved house twice etc since I've had it so it may have been knocked etc.

I was thinking about potentially buying a new telescope like a Skywatcher 130M, as the motorised may be easier with a little one as it can track etc.

[sloz1664]

Hi and a very warm welcome back to the Lounge

Steve

[Stu1smartcookie]

47 minutes ago, stokeben said:

How would I go about collimation? Not exactly sure what it is. I think I may need to do it though as we've moved house twice etc since I've had it so it may have been knocked etc.

I was thinking about potentially buying a new telescope like a Skywatcher 130M, as the motorised may be easier with a little one as it can track etc.

Hi , Welcome back ... i bought a laser collimator , its so easy to use ..it came with instrucions (you may need to collimate the laser first ) 

It cost me around £30 . i collimated the scope (250 flex tube dob) once and although i check it everytime it seems to be holding collimation . 

[stokeben]

1 hour ago, Stu1smartcookie said:

Hi , Welcome back ... i bought a laser collimator , its so easy to use ..it came with instrucions (you may need to collimate the laser first ) 

It cost me around £30 . i collimated the scope (250 flex tube dob) once and although i check it everytime it seems to be holding collimation . 

Great thanks I’ll have a look. Is there any other bits I need?

[cv01jw]

3 hours ago, stokeben said:

How would I go about collimation? Not exactly sure what it is. I think I may need to do it though as we've moved house twice etc since I've had it so it may have been knocked etc.

I was thinking about potentially buying a new telescope like a Skywatcher 130M, as the motorised may be easier with a little one as it can track etc.

You may be better off finding a tracking mount which will take your existing 150 tube - would depend on your budget though.

[Cosmic Geoff]

First, clean up the scope ( find a reliable cleaning guide online) - you want to blow dust off gently or wash it off with a mild cleaning agent - don't scrub the surfaces or use harsh cleaning agents like soda.

Then, try it out, and see how well it works. If not impressed, find a collimation guide online.  It's not hard to do collimation...

Don't buy a collimation laser - I never used one and have heard bad things about them.  Some people use a 'cheshire' collimator but the minimum tool is a bottle cap with a hole drilled through the middle.

Having sorted out the scope, try using it for a while before deciding to buy another. 150mm is a useful aperture.  If you do, there is plenty shiny hi-tech kit to choose from, and people here willing to advise.

[Louis D]

27 minutes ago, Cosmic Geoff said:

you want to blow dust off gently

Just don't use compressed air from a can:

[RT65CB-SWL]

Hi and welcome back to SGL. 

+1 for the cleaning & collimating advice as said above.

You say you want to change from a 'Dob' to something with tracking. My suggestion would be to purchase some tube rings, dovetail bar and a GEM/EQ. Then you have the best of both. Just my 2p's worth.

[Louis D]

30 minutes ago, Philip R said:

You say you want to change from a 'Dob' to something with tracking. My suggestion would be to purchase some tube rings, dovetail bar and a GEM/EQ. Then you have the best of both.

I would go with mounting a Dob on an equatorial platform over going the GEM route if tracking is desired.  Much lighter, more compact, and it keeps the original motions and eyepiece placement of the Dob.

[RT65CB-SWL]

4 hours ago, Louis D said:

I would go with mounting a Dob on an equatorial platform over going the GEM route if tracking is desired.  Much lighter, more compact, and it keeps the original motions and eyepiece placement of the Dob.

I thought GEM and EQ were the same thing - if not then what are the differences?

[Davey-T]

1 minute ago, Philip R said:

I thought GEM and EQ were the same thing - if not then what are the differences?

There are various designs of EQ  mounts one being the German Equatorial  Mount ( GEM )

Dave

[Louis D]

8 minutes ago, Philip R said:

I thought GEM and EQ were the same thing - if not then what are the differences?

A GEM is a type of EQ mount.  There are others such as the the yoke, open fork, and cross-axis mounts.

An equatorial platform is a platform that tips the entire telescope to counteract the motion of the earth.  It is a type of EQ mount, though it can only track for about an hour before needing to be reset.

[N3ptune]

@stokeben You can check out this very good collimation guide bellow. It will focus more on using a collimation cap or cheshire sight tube, both tools are effective tools. With absolutely no money, a simple 1$ cap could save the day to collimate a Newtonian. ?  You can build one yourself too.

http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/

Here is a cap from the land of the free.

https://agenaastro.com/rigel-systems-aline-telescope-alignment-eyepiece.html

[MarsG76]

On 06/09/2018 at 08:17, cletrac1922 said:

All I did, was using a swab of cotton wool, slightly damped in distilled water, wiped over primary mirror, to remove gunk, and wiped over with soft dry micro cloth

Instead of touching the mirror, which is always potential damage, especially if the cotton ends up being too rough!!! I spray the mirror with distilled water throughly to wash lose or loosen any gunk off it, than spray it with Isopropyl alcohol 100%, and wash away with distilled water... repeat for any stubborn areas... than just allow to dry... it'll dry clean and streak free.

 

[Whistlin Bob]

Hi and welcome back.

Lots of good advice above. If the Stoke part of your name is the Staffordshire version, then Rosliston Astronomy Group isn't too far away from you and they have a monthly session for helping with this sort of thing. There's one next Friday- see http://www.roslistonastronomy.org.uk/index.html. Bring your scope and you can get some hands on advice.

[kirkster501]

Welcome back.  Don't clean the mirrors unless you absolutely have to and they are caked in crud.

[JOC]

Follow the Astrobaby guide linked to above - do absolutely every step as it is written no matter how odd it might seem and you will get it perfect.  FWIW I bought a laser, decided it was un-necessarily complicated and got a Cheshire - then I followed the Astrobaby guide and its just a brilliant combination.  I can't recommend a Cheshire and the Astrobaby guide highly enough.