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Eyepiece or barlow? What next?


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Right, like many on here I've had my first telescope for a month and I'm already thinking of upgrades and would appreciate any advice on what would improve my viewing more.

I have a 70mm refractor and it came with 25mm, 9mm and 4mm eyepieces all K which I assume is Kellner. Also a 3x Barlow which I can't tell you much about other than it looks like the cheapest Barlow you could get.

So a few options I'm looking at are:

A decent Plossl (probably 15-20mm)

A decent Barlow

Or I did have a look at a couple of eyepiece sets on the FLO website.

So which do you think would be more worthwhile for planetary and lunar viewing.

Note- Budget is fairly open at the moment as this isn't something I'm buying right now. I have a habit of spur of the moment purchases so thought I'd try and do some forward planning for once.


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You don't say what the focal length of your scope is. This will help you decide as magnification is:

focal length of scope/focal length of eyepiece

I would suggest that the supplied eyepieces are very "cheap and cheerful" and that you would be wise to by a couple of decent quality eyepieces for your scope - you will really notice the difference!!

I suggest you read this tutorial:


There is another by "Warthog" somewhere(!) that is exellent and is laid out in layman's terms.

I would not advise a "set" as you are getting someone else's choice and probably paying for several bits and pieces (and a case) that you will seldom use - much better to buy just the bits you need!

Hope this helps.

Edited by Bizibilder
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Oops, while trying to keep as short as possible I knew I'd forget something.

Sorry, the focal length is 900mm

I did read that primer the other day but as soon as I see numbers my brain turns to jelly, but I'll give it another read now and concentrate properly on it.

Thanks for the advice too, I hadn't thought of getting a set but just happened to see them while looking at eyepieces and thought it might be a way of saving a bit of cash but I think you're right that I'd be better hand-picking.

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If your scope has an aperture of 70mm and a focal length of 900mm most eyepieces will work well with it - there is no need to spend lots on eyepieces.

Plossls will be an improvement over the ones supplied with the scope. For high power 120x or so would be your useful max so that would mean something like a 7mm (128x) eyepiece for high power, 15mm (60x) or so for mid power and a 25mm (36x) or 32mm (28x) for low power. You might not need to bother with a barlow and a decent one would cost you more than a plossl eyepiece would.

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Thanks a lot John.That'd explain why the couple of times i put the 4mm in I saw nothing then.

My thinking at the moment then is to get a mid power EP first since I don't have one at all, and then replace the 25mm and 9mm with something similiar as and when I can.

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