barlow problem

[raymo]

I have the SW 8" f/5 Newt which works fine at prime focus, and using EP
projection with the necessary adaptor, but I can't find a way of using just a barlow instead of an eyepiece. A barlow won't quite come to focus when fitted into the EP projection adaptor. Also can anyone tell me if
I can use filters at prime focus. What would I attach the filter to?
raymo

[Regulus (Trevor)]

Can't help. Don't know enough. However I did recently learn I could take the lens cell off my barlow and screw it into the bottom of the ep.
Might work for ur problem. Not a real solution but it might supply a stop gap.
Trev

[raymo]

Thanks for the suggestion Trevor, but I want to use the barlow without
an EP. The barlow will focus in my 80mm refractor, but not my Newt.
raymo

[doppler (Rick)]

I just slide the 1.25" t mount straight into the barlow and the barlow into the focuser without the eyepiece projection part fitted. Works on my 8"f6 newt.
Rick

[raymo]

Thanks Rick, sounds like a plan. Now I've just got to try and find a way
to use filters at prime focus.
raymo

[glend (Glen)]

What sort of barlow is it Raymo? As indicated some will screw apart, like the GSO 2" ED 2xbarlow which work fine with EPs in my big dob. I am about to try it connected to my DSLR - and have a set of adaptors of various thicknesses to work out the distance.

[raymo]

Hi Glen, it's a Celestron short 1.25" barlow, and the lens does unscrew. I also have a generic long barlow which does come apart. I don't need to
unscrew anything as Rick's method works fine.
raymo