My new Hutech 350d

[RB (Andrew)]

Originally Posted by tornado33

thanks.
Rocket Boy, yes the IR cut filter might stop excess IR light from coming through, however its mainly for refractors, as they focus IR light slightly differently, resulting in bloated star images if no filter is used. That doesnt happen with refector scopes.
Scott

Thanks Scott for that.
The reason I ask is because I know Houghy's used it on the 80ED and I would have thought that it's not necessary with an "APO" type scope like that.
Because if it is beneficial then I'd like to get one too.
BTW is the IR cut filter the same as a fringe killer filter?

Also what scope were these taken through?

Cheers.

[tornado33]

Thanks all.
Actually I wonder how much star bloat not using a filter might cause, as I was shooting some test shots through my 50mm F1.8 lens with no IR filter, and the stars looked hardly any worse than normal (always get some comatic stars near edges at F1.8 anyway). There might be some IR fogging thay may be reduced a bit by using a filter, hard to say.
My shots were taken with my 10 inch F5.6 scope, with baader coma corrector.
Scott

[EzyStyles (Eric)]

holyyy geee'sss. Those are one of the best i have ever seen!! Can you pleaseee be my mentor?