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i have a skywatcher explorer 130p. what eyepieces do you reccomend? are there any specific brands i should aim for ? and is a 2x barlow lens an option? i hear mixed feelings about barlow lenses and have no idea what the pros and cons are

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What do you have at the moment and what is the focal length of your scope?

I have a similar sized scope, a 5" Bresser short tube refractor. I have 10mm, 15mm and 25mm EPs that came with it, plus a Meade 40mm for wide views and a 6mm with good eye relief. I am also looking to upgrade - I have an 8mm Celestron XL on the way and will get a 4 - 5mm EP in the new year.

With hindsight, I should have got a 32mm eyepiece for wide views. The 40mm gives me a 8mm exit pupil - slightly wasted! I'm sure your scope has a larger focal ratio and could take a 40mm.

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hi Mick and welcome to the forum,

as far as eyepieces are concerned a nice set of possels are good to have and not expensive to buy, maybe a 10mm, 15mm, 25mm and something for wide views, maybe a 32mm. some say a barlow lens is a good thing as it doubles your available eyepieces as a 20mm eyepiece will become a 10mm eyepiece when used with a barlow, others don`t like to add a barlow because of the extra glass lens in the view, i don`t think it makes much differance, i`ve never noticed any using one and don`t bother too much about buying expensive ones, a nice mid range barlow is just as good in my opinion.

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thanks for that guys. im not sure what an exit pupil is :) or a possel but i will look into it i think from your comments a barlow is a viable option you people know so much stuff!!! i didnt realise how involved this hobby was when i bought my scope. its not going to put me off though!

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The exit pupil is the diameter of the bundle of light that comes out of the eyepiece. It gets bigger as the eyepiece focal length increases. If it's too big then it won't fit through the size of our dilated pupils (around 5mm - 7mm depending on your age) so some of the light that your scope has gathered is wasted. The diameter of the exit pupil is also affected by the specification of the scope as well as the eyepiece.

Plossl is an eyepiece design - that is the arrangement of glass lenses inside the eyepiece. You will come across many other designs such as Kellner, Nagler, Orthoscopic etc - choosing eyepieces can be more confusing than scopes in some ways !

Each design has it's strengths and weaknesses and some work better with some scope designs than others.

This primer on eyepieces is well worth reading:

http://stargazerslounge.com/beginners-help-advice/80772-eyepieces-very-least-you-need.html

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there is alot to learn Mick, i know nothing compaired to alot on here and people i know, but i always ask, sometimes at starpartys i still get my mates to align on polaris for me, i know how to do it but i never seem to get it 100% right L.O.L

if you are looking for a good price set of eyepieces i would recommend a set of Revelations,

First Light Optics - Revelation Photo-Visual Eyepiece kit

a very good choice in my opinion for the price

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im not sure of the purpose of that!! i dont get the physics..... i just like to point it at the moon and anything else that catches my eye... unproffessional or what?

You just need to know some basic maths so that you can work out how much magnification you are getting from a particular eyepiece in a particular scope. It's good to have 3-4 eyepieces to give you variation from low to high power.

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im not sure of the purpose of that!! i dont get the physics..... i just like to point it at the moon and anything else that catches my eye... unproffessional or what?

The purpose of what? Presumably you want to learn more, otherwise you'd just continue to use your existing eyepieces. Here is much of what you need to know: Eyepieces

Sorry that we use jargon from time to time, but there are some terms that are worth coming to grips with. If you Google "eye relief" you will immediately find: Eye Relief and Eye relief - Wikipedia, the free encyclopedia If you don't know, Google is your friend... :)

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Each object, each telescope and observer are unique Mick, so certain magnifications may be better for certain combinations. Most astronomers own three eyepieces--one high power, one medium, and one low--to cover various observing conditions. Usually these are in the range of 50x to 250x, since this covers everything from wide field to high power. A higher power may be useful for excellent nights, but will likely be an eyepiece that rarely gets used. A lower power might be good for wider fields of view, but only if the telescope can accept such a low magnification.

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im not sure of the purpose of that!! i dont get the physics..... i just like to point it at the moon and anything else that catches my eye... unproffessional or what?

i meant i m not sure of the purpose of aligning to polaris. i know where it is and everything, is this neccesary to locate certain objects?:)

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i meant i m not sure of the purpose of aligning to polaris. i know where it is and everything, is this neccesary to locate certain objects?:(

It all depends what type of mount you are using. An equatorial mount needs to have one axis aligned north (ie: pointing at Polaris) to enable it to track astro objects. An alt-azimuth mount (like a dobsonian) needs no alignment - you just put it down and point the scope where you want to view. The GOTO mounts usually need to be level, pointing north and then use a couple of reference stars so that the mount "knows" where it is and can work out where to point but the GOTO's all work slightly differently from one another :)

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