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Sideshow Bob

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Creating the thread by popular demand (i.e. 3 people so far but they are coming in hundreds) :)

Basically to share ideas, photos, anything useful related to amateur astronomy. I have ordered a DOB yesterday and likely to get it soon. Can't wait.

Got hold of traditional 10" dobsonian - base assembly was very easy as described by manual although I did watch a bit of youtube vids earlier so that helped. Just a bit of issue with finderscope and o-ring. Busy sorting out with help from members here.

Local links - local is lekker:
http://eridanusoptics.com/ - contacted Andrie on email/whatsapp. Very responsive.
https://telescopeshop.co.za/ - Met Neil in person; great guy - he suggested moon filter with telescope and I bought it and found to be of great use for moon.
https://shop.technopro.co.za/ - quick response on contact us page. Going to buy eyepiece soon and leave feedback.
 
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Sub.

It's been a while since I've actually done any amateur astronomy but I'm starting to miss it.

Also hankering for an 8" dobby now, based on the discussion on the other thread! :giggle:
 
I have been star gazing most of my life. It started back in high school when dad bought me my first cheapie telescope. Since then I have had various telescopes of which the last one was an Orion SkyQuest XT8. That I recently donated to an outreach program here is Cape Town after not using is for almost two years. Now I am contemplating getting something smaller and easier to transport for casual star gazing when ever I get a chance to leave the city.
 
DawieZA said:
I have been star gazing most of my life. It started back in high school when dad bought me my first cheapie telescope. Since then I have had various telescopes of which the last one was an Orion SkyQuest XT8. That I recently donated to an outreach program here is Cape Town after not using is for almost two years. Now I am contemplating getting something smaller and easier to transport for casual star gazing when ever I get a chance to leave the city.
Click to expand...

We've had the same thought, our 8" Skywatcher is amazing, but its a bit of a pain to transport.

If this was available in SA then I think it would be the perfect little travelscope:

6" is big enough to not be a toy, while the truss tube makes it small enough to handle with one person and fit in the backseat.

There's also the Meade LightBridge Mini 130, at 5" but without the handy collapsible trusses. It might be easier to find locally though.
telescopeshop.co.za

Meade LightBridge Mini 130mm

Astronomy for all with LightBridge Mini 130 * Parabolic Newtonian Reflector with an impressive 130mm (5.1") aperture * Lightweight (6.1kg) with a removable 650mm (f/5) optical tube * 26mm (25x) and 9mm (72x) eyepieces * 360° swivel mount and simple point-and-look design
telescopeshop.co.za telescopeshop.co.za
 
DawieZA said:
Thanks for the links and advice. I will be doing a bit of window-shopping the next few weeks. Will post here if I find something I like.
Click to expand...

Ignoring all the suggestions to go for 8", I got this yesterday. It was quick to put it together and had a personal wow moment that millions of amateurs must have experienced so far. Battling with collimation but will get there soon.

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:p
 
So, as mentioned above, I am battling with collimation finderscope adjustment. I think my basic problem is with o-ring provided with finderscope.

I think this is the way it goes into this groove, right?

1596955027376.png

and then I am trying to push it down (pushing it approx 1cm further than shown in picture) so that it fits just inside the holder.

What is the idea here with o-ring? Is it to hold it in position/marker so that we know till what point we push it down? Or is it so that those 2 screws (collimator screws?) tighten on the o-ring? That is what I am not getting it.

I would appreciate if someone can explain. I have scouted couple of forums but couldn't find exact answer. (but maybe I am not searching correctly). Seen many youtube vids and most of them show assembly of the base and then end almost there.

1596955065539.png
 
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Collimation isn't that tricky, but it does take practice. You don't need a laser. I do it by eye usually.

Are you talking about lining up the finder scope? Or collimating your primary mirror? Those pictures are too close up for me to understand the context.

Congrats on the purchase, I've actually been eyeing that one as well...
 
newby_investor said:
Collimation isn't that tricky, but it does take practice. You don't need a laser. I do it by eye usually.

Are you talking about lining up the finder scope? Or collimating your primary mirror? Those pictures are too close up for me to understand the context.

Congrats on the purchase, I've actually been eyeing that one as well...
Click to expand...
Thanks. I think I didn't put it well - leave collimation for now.

I think I am struggling with basics of where o-ring goes on finderscope. It goes in the groove (I think) but then how far do I need to push finderscope down? Do the 2 screws go above the o-ring, below the o-ring or are they going to push against the o-ring?

I find it that if I push it too much down, o-ring is getting displaced but if I keep it just above the 2 screws (plus the other 1 'screw') it stays in the groove, then finderscope is a bit wobbly. I mean finderscope is not as rock solid as the eyepiece side.

I have enlarged the pics a bit in earlier post.
 
chrisc said:
If you live near Cape Town, it may be worth joining the Orion Observation Group. They usually meet at Paarl on account of the clearer atmosphere, although not at the moment

Other astronomical societies and clubs in southern Africa

assa.saao.ac.za assa.saao.ac.za
Click to expand...

Club closest to us is in pretoria but I have heard most of such groups are closed because of social distancing requirement.

chrisc said:
There is also a UCT group, but a bit stuffy and disdainful of "outsiders"
Click to expand...
Not nice but what can one do.
 
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Finder scopes are a bit of a trick as well. I prefer red dot finders myself.

Also each one is slightly different. I'll have a look and see if I can find something instructive for this particular model.
 
newby_investor said:
Finder scopes are a bit of a trick as well. I prefer red dot finders myself.

Also each one is slightly different. I'll have a look and see if I can find something instructive for this particular model.
Click to expand...
Thanks, this is the manual and step 11, 12, 13 indicate what to do but I have a problem with 'until the rubber o-ring seats" as it doesn't really sit/lock. I will fiddle later in the afternoon.


1596957954082.png
 
I think you meant aligning the finderscope and not collimation as that is something you only do when the mirrors inside the telescope is out of alignment. ;)

So the o-ring goes into the narrower of the two grooves on the finderscope. The finderscope bracket then attaches to the telescope with the end of the finderscope bracket where the two adjustment screws are being closer the primary mirror end of the telescope. You then slide the larger groove end of the finderscope into the finderscope bracket from the secondary mirror end of the main telescope. The finderscope should slide into the finderscope bracket up to the point where the o-ring is out of sight (this can be a rather tight fit). The two adjustment screws on the finderscope bracket will tighten into the larger groove of the finderscope when you turn them. This will allow the front end of the finderscope to be somewhat fixed with the o-ring pressure and the back end of the finderscope adjustable via the two adjustment screws for alignment of the finderscope with the telescope.
 
LlamaParty said:
I got mine second hand on Facebook marketplace, for about R6k I think.

You can get quite a decent deal on a second hand scope.

... and then immediately go and spend all that money you saved on eyepieces!
Click to expand...
Where do you buy these typically? I will update the first post with all the links I get on this thread. Thanks.
 
I have heard that DOB is not great for AP but going to try it once I figure few things out. Planning to buy this

reliablestore.co.za

Telescope Camera Lens Adapter Metal Bracket 1.25inch T-Ring for Nikon Mount

Telescope Camera Lens Adapter Metal Bracket 1.25inch T-Ring for Nikon Mount Features: It offers 1.25 inch mounting sizes on telescope side. Attach for Nikon DSLR camera to the telescope with standard 1.25 inch It is compatible for Nikon camera Color: Black Material: Aluminum Size: 5.5cm x...
reliablestore.co.za reliablestore.co.za
 
newby_investor said:
Finder scopes are a bit of a trick as well. I prefer red dot finders myself.

Also each one is slightly different. I'll have a look and see if I can find something instructive for this particular model.
Click to expand...
I have heard the same but the cross-hair one is the default one that came with traditional dob. :-(
 
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