[xelasnave]

OK this is ruff but I hope you get the idea.

The idea is to baffle a dew tube to restrict stray light as well as help with a dew problem...but for me it is all about restricting stray light..a bright star or a street lights though not in he field of view sends light all around ...this thing minimises the stray light.

Hubble use this principle.

I had the idea and made one but was happy to later find Hubble was into the same idea...If they use it there must be something to it ...right?

I hope the pictures give you some idea but please note this is not a real one but some paper cutouts to help understand how I make them..I can't show a photo of the one I use on the 80mm cause it is up North and I am in Sydney.

So a cardboard tube with disk's either end one housing a smaller cylinder that fit your scope.

I place rubber strips in this one to have it fit well.

The baffles are created by folding a strip of cardboard and cutting small triangles out so it can fold in and form a ring and the uncut side you glue to the wall of the large cylinder.


I make them from cardboard and then layer it all up using flour water and salt and additional sheets of paper to make it strong..you can add resin to make it really strong but paint and lots of paper layers usually works..put in as few baffled say one each three inches..paint with black paint ...you can add sawdust of course and more paint.

Sorry this is so scant but I hope you get the idea...you can of course cut out circles for the baffled but you use heaps of sheets of cardboard...also you can just cut semi circles and add them in but I find the triangle thing works well..you can just cut lines but getting them organised can be a pain.
Any questions?
Alex

Notice the baffling and how far it extends.
Alex

Here is a shot showing the dew tube on the eighty mm.
Alex