What do I need to buy please?

[JOC]

So a tracking only 8" DOB - I'm guessing something that will maintain the XY axis arc, but not necessary find things ?  That sounds a much better compromise.

[Stu]

Hmmm, that's good but the trouble is they don't exist. Kim was suggesting that there is/was a 12" tracking dob but there isn't an 8" version.

Well, at least we squeezed hard enough to find the budget limit

The only other way I can think of achieving tracking with a manual dob is via an EQ platform. These are ingenious devices which allow your manual scope to track for extended periods of up to 45 or 50 minutes. You find the target and it stays in the view, simples.

This is a good one:

http://www.sumerianoptics.com/products/eq-platform/

Totally separate purchase so you don't have to buy it at the same time. There is a little setup in terms of positioning the platform on a level surface pointing north but it's very simple.

Any good?

[JOC]

Hi Stu. that's an ingenious looking device.  I assume I'd sit the white circular platform of the 8" DOB onto that and then it's designed to slowly lift and move the setup through the necessary arc without it all falling over in the process?  Would that one work with the 8" system we've been discussing?  That sounds like it would do the trick.  I think with a decent reference source finding things in the sky per se probably isn't beyond me, indeed at a personal level I could probably manually track an object, but when I start considering parents looking at something already in view, maybe younger family members who might nudge things etc. something that gives some steady time for everyone to take a look sounds a worthwhile purchase to make all much more family friendly. 

Ah, reading more - they are specific for each latitude - yes?  That's OK for a system that is going to be in a back yard.

[Stu]

Yes that's right. They are designed to take scopes up to probably 16" so are well within limits with the 8".

In theory they need to be setup accurately for your latitude but the reality is that within a tolerance they remain accurate enough for normal visual use. Just make sure you get one which is in the correct range for your latitude, probably 52 degrees North?

They are actually pretty stable, the tilt range they go through is only a few degrees, maybe 10 for end stop to end stop so the scope remains stable.

[brantuk]

Shame - it's a great scope with a lot of very useful good quality mods - and having purchased from that seller in the past I know he keeps his kit in excellent condition. It's a bargain too - very well priced.

(Woops - skipped a page when I hit "Post" - I was answering OP's comment on page 3 about the 12" dob lol)

[JOC]

brantuk, yes, I read the ad on this website and thought that it sounded rather interesting, however I absolutely, categorically, emphatically, definitely, won't be persuaded to find that amount of cash to spend on this project - which will probably only end up being a high days and holidays thing anyway.................and despite all that ;-) As I previously mentioned Oban is (luckily!) a very, very long way from me (Deepest Essex) - bank manager breaths a huge sigh of relief.

[brantuk]

Gotcha JOC

Yes it's an expensive hobby and best to start small before you know how deep you really want to go with it. The 8" dob with the Sumerian tracker which Stu suggested looks like a feasible solution for you.

[scarp15]

1 hour ago, JOC said:

Hi Stu. that's an ingenious looking device.  I assume I'd sit the white circular platform of the 8" DOB onto that and then it's designed to slowly lift and move the setup through the necessary arc without it all falling over in the process?  Would that one work with the 8" system we've been discussing?  That sounds like it would do the trick.  I think with a decent reference source finding things in the sky per se probably isn't beyond me, indeed at a personal level I could probably manually track an object, but when I start considering parents looking at something already in view, maybe younger family members who might nudge things etc. something that gives some steady time for everyone to take a look sounds a worthwhile purchase to make all much more family friendly. 

Ah, reading more - they are specific for each latitude - yes?  That's OK for a system that is going to be in a back yard.

Do consider how long parents or younger family members might actually spend time looking through your scope, for example at the moon. My experience of this (parents, nephews, nieces etc) and involving a manual 8" dob is not very long. An EQ tracking base might be quite nice for prolonged and dedicated planetary observing perhaps, but equally the money could be spent on a couple of explore scientific wide angle eyepieces. Nudging can quickly become second nature and younger family members at least, as instructed, are not afraid to give the scope a gentle tap. It will also convey to family the natural rhythm and movement of celestial objects.

[rockystar]

5 hours ago, Stu said:

Hmmm, that's good but the trouble is they don't exist. Kim was suggesting that there is/was a 12" tracking dob but there isn't an 8" version.

Well, at least we squeezed hard enough to find the budget limit

The only other way I can think of achieving tracking with a manual dob is via an EQ platform. These are ingenious devices which allow your manual scope to track for extended periods of up to 45 or 50 minutes. You find the target and it stays in the view, simples.

This is a good one:

http://www.sumerianoptics.com/products/eq-platform/

Totally separate purchase so you don't have to buy it at the same time. There is a little setup in terms of positioning the platform on a level surface pointing north but it's very simple.

Any good?

at the risk of side tracking the thread:

when using one of these, I presume you lock the attitude clutch, but would you also need an azimuth brake to stop it spinning?

[Stu]

3 minutes ago, rockystar said:

at the risk of side tracking the thread:

when using one of these, I presume you lock the attitude clutch, but would you also need an azimuth brake to stop it spinning?

Not sure I get what you mean Lee. You find the object as normal and then leave the scope still as you normally would. The normal friction holds the scope position as the tilt really isn't enough to move the scope. I struggle to get my head around the geometry of it but they do work very well. I will use my dob on mine when I get a chance, but have mainly used it with  tripod on with an Giro-WR head for solar observing, it tracks very nicely. You can also put a camera on a tripod on them for widefield AP, Milky Way shots etc

[Stu]

3 minutes ago, rockystar said:

at the risk of side tracking the thread:

when using one of these, I presume you lock the attitude clutch, but would you also need an azimuth brake to stop it spinning?

Not sure I get what you mean Lee. You find the object as normal and then leave the scope still as you normally would. The normal friction holds the scope position as the tilt really isn't enough to move the scope. I struggle to get my head around the geometry of it but they do work very well. I will use my dob on mine when I get a chance, but have mainly used it with  tripod on with an Giro-WR head for solar observing, it tracks very nicely. You can also put a camera on a tripod on them for widefield AP, Milky Way shots etc

[rockystar]

thanks @Stu I was just thinking that gravity may cause the base unit to spin when the tilt gets to a point - so I was thinking of a mod to add a breaking system - but it sounds like the friction is enough to prevent this from happening.

[brantuk]

A small az brake would be easy to rig up if needed. A sliver of wood between the base board and turntable with a small G-clamp would do it - not too elaborate really.

[JOC]

I'm back and just bumping this thread so I can easily find it over the new week.  Funds have duly arrived and sorting out a telescope is a serious possibility.  I'm just trying to make sure that I have somewhere inside that I can at least store the optical side of the Dob setup.  I'm guessing cool, but not open to the damp is preferred - i.e somewhere like a fully enclosed porch which is periodically open to the inside atmosphere of the house.  I like the scaling picture vs a human figure earlier in the thread as this gives me a good idea of the sort of size I am looking at. - if I am going to spend a lot of cash, I want to make sure it can be looked after.  Usefully my son's school has purchased a new telescope (he can't remember exactly what, though it does sound as though it has a Goto style finder attached) and for the next few weeks of dark nights are going to try and run an astronomy club which he intends going to, so he should learn a lot about what and how to point telescopes at in the night sky. 

Now the biggest question is how much to afford ......... the 8" Dob with the rather clever EQ platform, or be naughty and go for something larger...............I guess if I do the common sense route I stick with the 8" and get some better eyepieces if I want to spend more cash.

[Jimtheslim]

Depends just how dedicated you will be in terms of lugging it in and out to the garden. I have a 10" dob and love it, however even for a fit man in his early thirties, I wouldn't fancy anything bigger or heavier.

Oh and if you go for a dob, don't forget one of these....this one is way overpriced but good for illustrative purposes

http://www.homebase.co.uk/en/homebaseuk/standard-water-butt-stand-013278

[JOC]

A water butt stand LOL!  To put them on so you don't crick your neck to much - Yes?  I can see the sense in the suggestion funny though it sounds.

In terms of light pollution, how close does it have to be to notice it?  If I set it in the garden at the back of the house and turned off the adjacent kitchen light would that be sufficient?  Or is it worth lugging it 100 Yards further down the field?

 

[Charic]

 Stay in the shadows, and try not to look at any lights. A darker site is worth the effort. 

As for the butt, it just raises the scope for those who stand, or for tall people who sit. I'm 5' 8" and sit. 

[Dave In Vermont]

Rather than read through a bunch of old replies - lazy me mode - I'll simply ask: Do you have a copy of Stellarium yet on your computer? Stellarium is a very complete 'planetarium-program' which gives you a very realistic view of your nighttime-sky set to your own location. Which you can make go as deep and detailed as you wish. Similar software-programs can cost 2 hundred £££'s easily. But Stellarium is totally free - for keeps. Really. It will show you everything up there and within the ability of any telescope to see.

So here's a link and my Cut & Paste, and I'll leave you with a screenshot of mine - which is quite complex for my purposes. Not to worry - it's quite simple right off. It's up to you to program what you wish it to show you. Instructions included:

---------------------------------------------------------------------------------------------------------------------------------------------------------------

On this link is the main page for downloading Stellarium. Choose which version is correct for your computer. Here you go:

http://www.stellarium.org/
 
As for instructions, a full copy of them is bundled with the program that you download. But if you need another copy for some reason, these can be downloaded here:
 
https://sourceforge.net/projects/stellarium/files/Stellarium-user-guide/0.15.0-1/stellarium_user_guide-0.15.0-1.pdf/download

This program is quite large, so download when you have a few minutes. I'll leave you with a screenshot of mine. Please know I am an experienced user. When you first open your copy, it will be far less advanced and very easy to understand.

Enjoy!

Dave

---------------------------------------------------------------------------------------------------------------------------------------------------------------

 

[Cosmic Geoff]

I could be mistaken, but I get the impression that JOC has not visited a specialist astronomy store to see what these telescopes look like in the metal. Seeing the real thing could make apparent what one can't see on a website - for instance an 8" Newtonian OTA weighs at least 9 Kg and getting one of those out of doors and onto its mounting in the dark, without assistance, is no joke. I had to fit a custom-made handle on mine so that I could get a firm grip on it.

Best way of seeing how your provisional choice might look deployed in your backyard - or stored in your lounge.

[Jimtheslim]

2 hours ago, JOC said:

A water butt stand LOL!  To put them on so you don't crick your neck to much - Yes?  I can see the sense in the suggestion funny though it sounds.

In terms of light pollution, how close does it have to be to notice it?  If I set it in the garden at the back of the house and turned off the adjacent kitchen light would that be sufficient?  Or is it worth lugging it 100 Yards further down the field?

 

Yes it raises it off the ground and gives a much more comfortable position to observe when standing. Otherwise get an adjustable stool (or both). I set up on grass which is pretty soft so a stool is out of the question for me most of the time, unless I put a wood board underneath.  Just make sure the ground is reasonably level and use a brick to weigh it down and avoid toppling. It is the best piece of equipment (besides a Telrad) that I have invested in and only cost a fiver.

As for LP you can look your location up on several maps available on the internet. As mentioned above, try and stay in shadows and shut of all unnecessary lights. How nearby LP affects your views depends on a number of things.

[JOC]

No, I haven't visited an astronomy shop - its a sound notion to do so, but a countryside location also means that such things are likely to be a fair trip away.

I found a light pollution map - we actually sit in a 4-8 Nanowatts/cm2/sr (we are next to a factory), within 300m this drops to 2-4 Nanowatts/cm2/sr and within about 500 it drops to less than that.  I am surprised it doesn't sound better than that as I thought we were quite dark (though I know the factory throws a bit of light out), but we do have a large tree lined barrier around the factory and that might lessen  the impact in our garden.

 

Oh, yes, and we did discover Stellarium some time ago, I think its on my son's portable

[JOC]

OK, many thanks for all the help.  I kept looking at the 8" dob with the EQ platform, but the only place I could really find such a thing from was that Sumarian website and you had to mess around making contact, emails then I guess a specific build and it will only be valid at certain locations, so I ran the cost up with the 8" Dob and was hitting somewhere approaching £700.  So I thought in for a penny in for a pound and have bitten the bullet and ordered this:  https://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-200p-flextube-goto.html From what I see these things have second-hand value if well looked after so that is what I intend to do and see how we get on with it. 

What do you think?  Will it do a beginner?  What sort of things will I ultimately be able to do with it if we want to?  Will we be able to see DSO's, look at the sun with appropriate filters, take pictures (I'm a keen photographer - that shot of the moon as my forum pic is one of mine), be able to see all the planets to some degree?  etc.  (I've taken  look at the rein in your expectations thread in the beginners section and showed my parents that we won't be able to see things like Hubble and Cassini - incidentally that is a brilliant thread), is such a thing dare I suggest 'portable' to any degree - if we did find an astronomy group would we be able to visit with our own telescope and would we be laughed off the planet for having the wrong kit?  The other thing I've been wondering at with astronomy is, is it just a 'look at things' hobby or can amateur observers actually contribute to science in any way? 

Anyhow, I am sure with our own kit the questions will flow thick and fast.  Now, just how do we book these clear nights......?  The new school astronomy group got all the permissions sorted for a late night based on the weather forecast last Friday and there was 100% cloud cover so they all came home!!

[Charic]

.....the £289 Skyliner 200P Dobsonian  ( https://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-200p-dobsonian.html ) would give you the same views,  especially under the skies you mention, only  at a fraction of the price, if your new into the hobby. But its still a fine scope, the one ordered.
The bells and whistles is where the extra cost is inherited, on the system your ordering? With the Dobsonian, you do it all yourself, which I find more interesting.

You still may need some 'extras'  like a jacket for the scope,  dew shield unless one is supplied?  a power pack or mains supply  (unless it all runs on AA's?)
One thing my Dobsonian cant do is track, so for astro-photography, you may have a solution, My intention is to keep my scope for this things I view now, but for astro-photography, I`ll probably get an ED80  or slightly larger?
Take a look at the book, making every photon count. https://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html

[JOC]

Well I was drawn to the Dobsonians  and the one I ordered appears to be a Dob.  Yes?  My family were very keen on spending time viewing rather than continually finding and realigning things and were drawn to the goto tech. and I am keen to see the potential of photography.  Thus although I guessed it might only perform as well as the other skyliner 200P it seemed worth the extra as if I'd have ordered an EQ platform I'd have been approaching a similar cost.

[rockystar]

It's an excellent telescope on which ever mount you choose, you'll be able to see all the things you mention. Just make sure when viewing the sun to use a full aperture solar filter - don't use an eyepiece filter.

as for science, with the Juno satellite now at Jupiter, they are asking  amateurs to submit photos and to point out any potentially interesting things they may find. Variable star measurements are still very much in the amateur's lap.