Lens and setup advice

[eric]

Hi Guys and girls

I have a seben 700mm reflector telescope
and have used it a couple of times now.
its for my 10 year old son really so we are happy enough with the images we can see at the moment.
advice Im after is the uses for the differing lens's we have..
we got a great view of the moon tonight in and out of the clouds
using a 20mm..
what I want to know is, with the other lens that came with the scope
can someone please explain what the are used for.
I will list them here...
20mm as mentioned
12.5mm
6mm
4mm
barlow lens
1.5 erecting eyepiece
with hope
cheers guys

[brendan martin]

Hi Eric, the other eypeices are to increase magnification but to be honest other than the 12.5mm they will be unusable unless the scope is motorised, the erecting lens is for daytime use it will put the image the right way up (not required for astronomy) the barlow increases the magnification of your other eyepieces (eg: 20mm becomes 10mm if 2x barlow) again unusable unless motorised. we tend to use the lower power (20mm) to help spot objects and then up the power for closer views.
Hope this helps
Brendan

[eric]

Yes it does Brian thanks...
so basiclly its not worth using anything other than the 20mm
with the seben....

thanks for the reply