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jat
11-01-2014, 10:19 PM
Anyone out there help an idiot ??just been given a Seben ref: N76/700/3998 and realise its rubbish but being an engineer , before I look for something better,need to know why this one does not work>>>>

when looking through the viewing tube without the lens ,I can see the reflection of my own eye, this indicates to me that the reflecter and prism
are in place however, when viewing with lens in place the view is blank.
All I can think of with my limited knowledge ,is that there should also be a lens on the front where I have a plastic plug, the centre of which has a of 40mm dia and at the rear of this, a a recess of 48mm x 7mm depth
should a lens be in place here ? if so ,what should I be looking for? if not can someone enlighten me as to cause ::help:

MrB
11-01-2014, 10:57 PM
Hi John,

There is no lens in the front of the telescope.
From photo's I can find of the scope via google, the plastic plug you mention is a moon filter* is probably a dust cap. You will want to remove this.

The following diagram and page may help you:
http://www.derbyastronomy.org/images/NewtonianReflectorDiagram.jpg
http://starizona.com/acb/basics/equip_telescopes_newtonians.aspx

*Edit: Looking at the photo's again, I think the moon filter is much smaller than it appears in the pictures I found, my guess is it pushes over the eyepieces.

Occulta
11-01-2014, 11:02 PM
Hi John and welcome to IIS :hi:

It appears that you have the front cover of the telescope still in place.

Make sure that is removed and see how you go.

Chris

doppler
11-01-2014, 11:06 PM
It looks like it is a small reflector so you need to take the complete end cap off not just the smaller 'plug". The moon would be the easiest target to test it out on.
Rick

raymo
12-01-2014, 01:45 AM
Seben have been in business along time, and their products are
normally as good as any other budget level supplier's, so I think that you should get it up and running before passing judgement on it. Unless it
has had a hard life and has sustained some damage, you will probably
be surprised by what the little reflector will show you.
raymo