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Dalestronomy
03-07-2013, 08:58 PM
Hi all,

Bought a Celestron Astromaster 130EQ a couple of months ago and am loving it. Recently bought the accessory kit, which included eyepieces, filters and a barlow lens (2x).

I've no idea how to use the barlow lens though!
This is what I've done:
Taken off the cap of the barlow lens
Unscrewed the back of barlow lens
Put barlow lens in eyepiece hole of telescope
Put eyepiece in barlow lens

But any star/ planet just looks super blurry, and I can't focus any further.

What am I doing wrong? Probably something very stupid! But can You please help?

Thanks!!

glend
03-07-2013, 09:03 PM
Don't unscrew the bottom of the Barlow, your removing a lense when you do that and simply altering the focal length of the eyepiece which is why it is blurry. There should be a back plastic cap on the bottom of the Barlow just pull that off then it should be fine.

malclocke
03-07-2013, 09:06 PM
All sounds fine to me, with the exception of 'unscrewed the back of barlow lens'. Not sure what you mean by that?

Dalestronomy
03-07-2013, 09:34 PM
Ahhh! There's a cap on there!!

Didn't realise it was two parts, couldn't for the life of me work out why the lens was inside that bit, and how to use it!!

Thanks!

Wavytone
03-07-2013, 09:36 PM
1. Take the cap off the Barlow Lens. Do not unscrew the lens from the barrel. Might be a good idea to check it is clean, if you have unscrewed it its probably covered in sticky fingerprints by now.

2. Insert the Barlow lens into the focusser, the skinny end (where the lens is) goes into the focusser, the fat end (empty) sticks out of the focusser.

3. Insert eyepiece into the fat end of the Barlow.

4. Try focussing the telescope.