solar filter on small mini truss dob.

[Lux1]

Can i fix a solar filter across the top of the arrowed section blocking the light and heat from entering the lower tube? Would save making a shroud I think. Any ideas. I'm guessing that heat is only created from unfiltered light hitting the primary so in theory you could place a piece of baader film in between the primary and secondary?

[Macavity]

I think the problem will be that the light would then have to pass TWICE through the filter to reach the eyepiece - Thereby rendering the sun invisible. Since the topmost ring is of similar design, it must be EQUALLY feasible to do something, in a more conventional way? An interesting project, anyway...

[Merlin66]

Yes, a double pass throught the baader Solar Filter would be pushing things....can you wrap the open section with a piece of cardboard and fit the film SECURELY to that?

[Roel]

No, mounting the foil on top of the lower tube will not work. When you look through the eyepiece youl'll be mainly looking at 99% reflected sunlight from the foil. It wils be almost like looking directly in the sun via 2 flat mirrors (the diagonal and the foil).

[Merlin66]

very good point!!

[Lux1]

No, mounting the foil on top of the lower tube will not work. When you look through the eyepiece youl'll be mainly looking at 99% reflected sunlight from the foil. It wils be almost like looking directly in the sun via 2 flat mirrors (the diagonal and the foil).

That's a very good point, - I hadn't thought of it like that.

I will have a go at making a shroud then. Can I use some offcuts on apair of 10x50 binoculars?