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    josmith16's Avatar
    josmith16 is offline Main Sequence
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    Default Focal Reducer for Mak-Cass questions...

    I own a 127mm Mak-Cass, which has a focal length of 1540mm, and might consider in the future possibly getting a 180mm Mak-Cass, which has a focal length of 2700mm. I have read a few articles about that fact that because the Mak-Cass has a long focal length that it is not ideal for DSO viewing because of the small TFOV. I saw some people have bought an SCT adapter and a focal reducer for the Mak-Cass. I'm curious if there are any focal reducers,which are made to adapt to the Mak-Cass without a adapter, and I'm assuming that I can add a focal reducer to the end of my EP and not have to use it with a camera. Is ther a focal reducer that just screws on the my eyepiece? Suggestion or comments concerning the focal reducer and adapter would be appreciated. And if anyone can explain any disadvantages to using a focal reducer, I would appreciate that too.

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    Maverick199's Avatar
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    Normally a Focal reducer attaches or threads onto the visual back of your OTA. Focal reducers can come in two varieties.

    1. Focal reducer 0.63x which threads onto the Visual back of your scope.
    2. Focal reducer 0.50x whcih threads INTO your eyepiece barrel, like GSO for example.

    Based on their number, your scopes focal ratio will decrease, thus enabling you to cover a wider field of view.

    However, your 127mm Mak Cass's FoV should be adequate enough to view DSO's, except Double Clusters of Pleiades for example where your ratio wouldn't cover the field.
    "So many questions, so much to learn, so little time".



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