Bahtinov for a 200p Dob

[autonm]

I have a 200p Dob - looking at FLO - they have a Bahtinov for 200m Newtonian. However should I get the f5 or f6?

the 200p Dob has a f5.91 rating - so should I go with the f6?

(or are there any alternatives?)

Thanks

[Jannis]

I'm guessing F6 would be closest, yes. Unless you use any focal reducers of course. I don't know the actual difference on those two though, but i dubt it's critical in any way.

Alternative is to simply make one yourself. Quite easy, and absolutely free.

[ronin]

Ring FLO and ask, I spoke to them some time back and as I recall the masks are made, meaning they do not keep one of each in stock, so they could easily take your specification and dial it into the cutter and produce one for your scope.

[Steve Ward]

Talk to Keith at StarSharp (http://www.morris-engraving.co.uk/starsharp.htm)

He'll make one to your exact specifications , laser cut and will last a lifetime.

Steve.