Field flattener, Williams old one.

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Altocumulus
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Field flattener, Williams old one.

#1

Post by Altocumulus »

Does anyone have a William Optics 102GT with an old style flattener/reducer, and can post an image or two showing their setup so I can see how it all fits together.
This is the first time of trying to use the flattener, not needing it on solar stuff...

Back focus diagrams are all well and good, but often don't include the telescope and where the focus tube is....

Geoff
Just call me Geoff....

I do what I do because I can, and because I want to.
It doesn't mean I know what I'm doing :mrgreen:
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Altocumulus
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Re: Field flattener, Williams old one.

#2

Post by Altocumulus »

If the 'normal' focus distance is 277.44 mm without the FF, and the
back focus for the FF is 69.9mm.

In normal solar work the distance is assisted by use of a solar wedge or CaK module - so I can only roughly guess I'm achieving the correct distance.

How much does the focus tube have to be 'out' from its housing, when the FF is included - would a diagonal make it any easier?

Geoff
Just call me Geoff....

I do what I do because I can, and because I want to.
It doesn't mean I know what I'm doing :mrgreen:
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