*** The Official Astronomy & Universe Thread ***

[BFCTom]

Could anyone in here recommend me a decent starter telescope? Would like to view up to the outer planets if possible, few hundred quid budget.

It's something I've been wanting to get for a while, but I'm a bit overwhelmed by all the available kit.

 

[NickK]

The best bang for buck for beginner visual is usually a dobsonian.

Visual requires aperture so that you collect enough light for your eye to register the objects.

The next thing is that Moon/Planets and Deep Space Objects differ in their requirements. Moon+planets need long focal lengths to see details - starting at 910mm for the moon going up to 2000-3000 for planets.

At this fl a reflector is best (and cheaper) - both dobsonians and newtonian (they are the same thing but the dob sits on the ground rather than a proper mount). You'll also want to have some stability as things beyond 1000mm fl will start to show up vibrations very easily - again this is where a dob wins (unless you're spending ££££ on a mount).

Because the dob mounting is so cheap, you'll get more aperture etc at the expense of accuracy of tracking - the basic dob you move by hand (even some expensive high lambda mirror ones I've seen are manual too). You can motorise them - both tracking and GOTO but I'd leave this...

If you want to take photos using a web cam - then a newtonian on a equatorial (EQ) mount is better than a dob. It offers better tracking but cheap mounts will suffer from stability.. so fill the legs of the stand with sand to help..

That said - either way I would go for a minimum of 150mm aperture (primary mirror size). Preferably 200mm.

Now to the disadvantage of mirrored scopes - size.. the dob and the newt will be quite large.. probably larger than you're expecting (or your other half may expect ).

If you want to wheel it out and have a look then a dob is great. No setup/alignment just point and look. The newt does things differently.. I've seen some really good views through a 16" aperture dob but also some great webcam astro-photography results from one too.. if you start down the dark side (astro-photography) then that couple of hundred will multiply..

Examples of dobs: http://www.firstlightoptics.com/dobsonians.html
Examples of newts: http://www.firstlightoptics.com/reflectors.html
Then if you go more specialist to planets then maksutov and casses..

 

[Cosimo]

http://www.jb.man.ac.uk/astronomy/nightsky/

 

[Tibbz2]

I'm stuck with a 114mm reflector, got it as a gift... I'm still wondering what to do over the next few years. I was thinking of using this until I get good and learn the ropes, then buy a higher end scope, but the trouble is in a few years I will be most likely living in built up areas (while at Uni) so maybe there is no point?

 

[BFCTom]

The best bang for buck for beginner visual is usually a dobsonian.

Visual requires aperture so that you collect enough light for your eye to register the objects.

The next thing is that Moon/Planets and Deep Space Objects differ in their requirements. Moon+planets need long focal lengths to see details - starting at 910mm for the moon going up to 2000-3000 for planets.

At this fl a reflector is best (and cheaper) - both dobsonians and newtonian (they are the same thing but the dob sits on the ground rather than a proper mount). You'll also want to have some stability as things beyond 1000mm fl will start to show up vibrations very easily - again this is where a dob wins (unless you're spending ££££ on a mount).

Because the dob mounting is so cheap, you'll get more aperture etc at the expense of accuracy of tracking - the basic dob you move by hand (even some expensive high lambda mirror ones I've seen are manual too). You can motorise them - both tracking and GOTO but I'd leave this...

If you want to take photos using a web cam - then a newtonian on a equatorial (EQ) mount is better than a dob. It offers better tracking but cheap mounts will suffer from stability.. so fill the legs of the stand with sand to help..

That said - either way I would go for a minimum of 150mm aperture (primary mirror size). Preferably 200mm.

Now to the disadvantage of mirrored scopes - size.. the dob and the newt will be quite large.. probably larger than you're expecting (or your other half may expect ).

If you want to wheel it out and have a look then a dob is great. No setup/alignment just point and look. The newt does things differently.. I've seen some really good views through a 16" aperture dob but also some great webcam astro-photography results from one too.. if you start down the dark side (astro-photography) then that couple of hundred will multiply..

Examples of dobs: http://www.firstlightoptics.com/dobsonians.html
Examples of newts: http://www.firstlightoptics.com/reflectors.html
Then if you go more specialist to planets then maksutov and casses..

Thanks for that, will look into the options based on your advice

 

[NickK]

Thanks for that, will look into the options based on your advice

In terms of eyepiece expectations:
* moon - should see lots of interesting stuff - anything up to about x220 magnification
* planets - should see lots of details depending on the planets.. I've used really high mag on mars on a dark site.
* DSOs (nebulas and galaxies) - you'll not see images like the hubble! usually galaxies are smudges with small apertures. Through the 16" dob, with a televue EP (more than your budget!) on a darkish site I could see M51's spiralling arms and some bluishness.. M42 is very bright so you'll start seeing lots visually on that.. DSOs are the opposite of planets.. this is where light gathering rules and magnification takes a back seat.. often it's x50 mag or even less for a wide field with lots of light.. as soon as you magnify your eye will not be able to see it (unless you have large aperture/mirrors).

I have a 4" refractor which uses lenses rather than mirrors.. I can see the moon in good detail, planets are good at 1340mm but it's still smallish - mars I can see the dark blotches, saturn I can see the separation between the rings and the planet, venus I can see the variations of the clouds.. At 670mm I can see DSOs as smudges (although M42 I can see more although with the naked eye you can see it). However this is an APO refractor which is outside of the budget - you'll get the same views with the reflector (the refractor wins in other ways but unless you take up astro-photography.. it's not going to impact).

Only on Mauna Kea (Hawaii).. I could see stuff that I can't see through the scope (light pollution) with my naked eye. So a dark sky makes a big difference!

Telescope is more about gathering light first then about magnification.

Lastly - the eyepieces that are usually provided are "ok".. but not the best thing in the world. If you find yourself looking around more.. treat yourself to a Baader eyepiece which will be the difference of day and night (both in light transmission and the detail that you'll see).

 

[NickK]

I'm stuck with a 114mm reflector, got it as a gift... I'm still wondering what to do over the next few years. I was thinking of using this until I get good and learn the ropes, then buy a higher end scope, but the trouble is in a few years I will be most likely living in built up areas (while at Uni) so maybe there is no point?

You can get light polution rejection filters.. but uni hasn't stopped some people from continuing.

If you keep your scope then one option is to go for better eyepieces.. that means better light and better definition. I was amazed at the difference between the eyepieces bundled with my little Vixen A80Mf and the Baader Hyperions I use now... however it may be better for you to splash out on a pair of binoculars..

Sandrine bought me a pair of Pentax 12x50 ACFs. Although I would probably have gone for a pair of 10x50s instead (you need light rather than magnification). I use them quite a bit for finding targets (I don't use GOTO) as they give better field of view and show fainter targets than the vixen..

 

[Greg0986]

10mm with a 2x Barlow gives the same magnification as a 5mm normal lens iirc as long add you have a good quality Barlow the image shouldn't suffer iirc.

What scope do you have?

Celestron Astromaster 130EQ. Cheers!

 

[Tibbz2]

You can get light polution rejection filters.. but uni hasn't stopped some people from continuing.

If you keep your scope then one option is to go for better eyepieces.. that means better light and better definition. I was amazed at the difference between the eyepieces bundled with my little Vixen A80Mf and the Baader Hyperions I use now... however it may be better for you to splash out on a pair of binoculars..

Sandrine bought me a pair of Pentax 12x50 ACFs. Although I would probably have gone for a pair of 10x50s instead (you need light rather than magnification). I use them quite a bit for finding targets (I don't use GOTO) as they give better field of view and show fainter targets than the vixen..

I have been looking into binoculars for a while because like you say I hear they're quite useful for finding things... I certainly need to get some different eyepieces soon too! I guess i'll sort the Uni situation out nearer the time and do what's best... It's still 2 years or so away.

 

[NickK]

I have been looking into binoculars for a while because like you say I hear they're quite useful for finding things... I certainly need to get some different eyepieces soon too! I guess i'll sort the Uni situation out nearer the time and do what's best... It's still 2 years or so away.

I can say from 4 years of uni experience.. at Uni the last thing on your mind will be Astronomy

 

[Tibbz2]

I can say from 4 years of uni experience.. at Uni the last thing on your mind will be Astronomy

Haha I guess that's the main issue I should think binoculars would be a nice thing to have though, just to take a look now and again when I can

 

[Tibbz2]

Currently trying to get the RDF aligned for when I next use the scope, but it's proving a right pain in the arse. I've got it as tight as it will go to the scope but the dot is still out by a good cm on the display. There is no way it's getting there, might have to do some DIY on this... :/

 

[Tibbz2]

Sorry for yet another post but i'm stumped here. The RDF on my telescope just won't align whatever I do, it's still a mile out. Any ideas of how I can fix it? Vertically the dot is fine, but i've tightened the sight all the way to the 'left' but it still isn't far enough across.

 

[NickK]

My rdf has two screws that you can adjust the position of the dot (rather than having to play around with the mounting). These may be hidden under screw caps.

 

[Tibbz2]

My rdf has two screws that you can adjust the position of the dot (rather than having to play around with the mounting). These may be hidden under screw caps.

Sorry forgot to mention that I was infact using these, and these are at their limit

 

[NickK]

Sorry forgot to mention that I was infact using these, and these are at their limit

Hmm looks like the mounting is out by quite a way.. taking any drill to your scope is a last resort for so many reasons (everything from hot burrs damaging mirrors/lenses to bolts sticking into the optical path).

It may be better to use a wood block - attach the wood block to the existing finder mount then attach the rdf to the block. When I had this I used a metal door finger plate and used the existing guide bolt holes to make a flat point then bolted the rdf into the finger plate.

 

[Cyclone]

Just reading on The Mail (yes I know) that the Quadrantids (?) meteor shower is happening here tonight. Best place, apparently, is North & North East.

 

[Cosimo]

Stargazing LIVE is back on Tuesday 8th January and the following two evenings.

At 20:00 (Episode 1) then 21:00 (Back to Earth 1) on BBC TWO and BBC HD:

http://www.bbc.co.uk/programmes/b01py6vh

 

[Tibbz2]

Stargazing LIVE is back on Tuesday 8th January and the following two evenings.

At 20:00 (Episode 1) then 21:00 (Back to Earth 1) on BBC TWO and BBC HD:

http://www.bbc.co.uk/programmes/b01py6vh

Can't wait, missed it last year!

Hmm looks like the mounting is out by quite a way.. taking any drill to your scope is a last resort for so many reasons (everything from hot burrs damaging mirrors/lenses to bolts sticking into the optical path).

It may be better to use a wood block - attach the wood block to the existing finder mount then attach the rdf to the block. When I had this I used a metal door finger plate and used the existing guide bolt holes to make a flat point then bolted the rdf into the finger plate.

Shame, but this really is the last resort so it looks like i'll have to get around to doing it.

 

[Mik3]

Is it a normal mounting shoe like this one?

try loosen the screws and see if you can move it into the correct place.