Re: [APML] Focus

[William Mattil <wrmattil@ix.netcom.com>]

Stuart Heggie wrote:

>A couple of questions:
>My lens has an internal skylight filter and a front objective filter (to
>protect the lens). The determined focus is quite far from the marked
>infinity point on the lens (not unexpected as a lot of my pics are
>ruined by soft, bloated stars). Is it possible that the two filters are
>shifting the focus this much?
>
A little hard to say how much is too much. But yes. The focus will shift.

> They are both skylight filters. The
>internal filter came with the lens and I left it in - the external
>filter I bought to protect the objective.
>
>Second, anyone willing  to offer a pronunciation for "ronchi" so I don't
>sound like a goof if I ever talk to anyone about these?
>

Multiple knife edge :^)

Bill


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