I am confused by the lenses and what to buy for a 130p

[the lemming]

I'm not ashamed to admit that I am confused and bewildered by the magnifications and millimetre sizes of lenses for dobson telescopes. I am particularly interested in advice and options for my Heritage 130p dobson.

When I bought my first dSLR I quickly learnt that to get the best out of my camera I had to ditch the kit lens and buy the best optics that I could afford. Most importantly I had to compromise on an acceptable price that Little Miss Lemming would tolerate without wanting to convert me from a content little lemming to a miserable eunuch.

With all this in mind, and the modest price/build quality of my telescope, what lenses should I consider to replace the two lenses that came with my telescope?

Also How do I work out the 'real world' maximum zoom capabilities of my telescope, before things get silly and the image is impossible to follow or too faint to spot?

[wookie1965]

Have a read of these they will help you out a lot then ask any more questions.

http://www.swindonstargazers.com/beginners/eyepieces.htm

[themos]

In general we aim to cover "exit pupil" sizes of 6-7mm down to 0.5 mm. The exit pupil is your aperture divided by the magnification. That then becomes a minimum magnification of 130/7 = 18 and a maximum of 130/0.5 = 260. For your scope with a focal length of 650mm you need eyepieces between 650/18=36mm and 650/260=2.5mm. If you include a decent Barlow you'll be able to cover that range with perhaps 3 eyepieces.

[the lemming]

Have a read of these they will help you out a lot then ask any more questions.

http://stargazerslou...least-you-need/

http://www.swindonst...s/eyepieces.htm

I've read your first link a few times over the last couple of days but still find it confusing. However I did find the second link very informative and I understood it more. This could possibly be the fact that I may have grasped more in the first article without realising when I read the second article.

So, with all this in mind I am guessing that I have a theoretical maximum of x130 with a 5mm eyepiece

And with a Barlow I can get that up to x260?

But in reality would I really be able to go that high and would I even be able to view anything with a Dobson mount and budget telescope?

Realistically, what maximum range should I try to stick to?

What extra eyepieces would I best get to compliment my kit lenses of 10mm, 25mm and Barlow?

Questions, questions, questions. I realise, but it has taken me two years to mull over the choice of telescope with the help of advice on this forum. And if I may say, based on advice given, I made an excellent choice based on my needs, desires and tolerances of She Who Must be Obeyed.

[wookie1965]

Theoretical is 50x of aperture is maximum which is 250, you would need really good seeing conditions for this though. I would recommend a low medium and high power eyepiece such as a 32mm 18mm and 8mm with the barlow that gives you a 16mm 9mm and 4mm with the highest mag being the 4 mm giving 162x plenty for planets

[the lemming]

After quite a bit of reading I am confused about the eyepieces that came with my telescope which are Super 25 and Super 10.

Are these Plossl's or something else?

And good that they are, will I be better off replacing them eventually?

[AstroAdam]

After quite a bit of reading I am confused about the eyepieces that came with my telescope which are Super 25 and Super 10.

Are these Plossl's or something else?

And good that they are, will I be better off replacing them eventually?

With the Skywatchers, I think they're Kellners, which are one of the more basic types. The Skywatcher supplied EPs are actually not too bad at all (they actually did me for about 8 years!). However, you'll notice an improvement in sharpness, contrast and field of view if you go for something a bit better. the BSD Explorers on ebay from Skies the Limit - like this one - http://www.ebay.co.uk/itm/1-25-8mm-BST-Explorer-Dual-ED-eyepiece-Branded-Starguider-/160949760069?pt=UK_Telescope_Eyepieces&hash=item25795a7045 - are really good for the price.

Bought the 8mm one the other week, and am really impressed with it. Going to gradually replace my Eps with these I think.

[wookie1965]

As AstroAdam as said the skywatcher supplied ones are not brilliant the 25mm is not bad the 10mm leaves alot to be desired i would advise get something in this range first to replace that like the BST 8mm they are very good value for money the 15mm has just been voted best in its field in sky at night magazine they are very good eyepieces and for £47 you cant beat them.