Etalon to objective gap

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axlefoley
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Etalon to objective gap

Post by axlefoley »

Is the gap between the etalon and the objective critical.

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Re: Etalon to objective gap

Post by marktownley »

Don't think so. I've never really payed much attention to it when mounting external etalons on my scopes, and have never noticed any adverse results.


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Re: Etalon to objective gap

Post by axlefoley »

Thanks Mark I was worried that I had a friend make an adapter to mount a SM90 to a SkyWatcher scope not giving any thought if there is a set distance.

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Re: Etalon to objective gap

Post by Merlin66 »

No, there's no critical spacing required with an external etalon.


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Re: Etalon to objective gap

Post by axlefoley »

Thanks Ken.

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Re: Etalon to objective gap

Post by swisswalter »

Hi Alan

exact what Mark and Ken wrote


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