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Thread: Where to set Focus?

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    Default Where to set Focus?



    When imaging DSOs where should one set their focus? My logic (?) says do "long" exposures of the DSO area with a Bahtinov Mask and focus on a star there. Is that correct or should I pick a star bright enough to focus on through Live View in BYEOS?
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    Default Re: Where to set Focus?

    Use your mask to focus on a bright star, and then slew to your target.
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    Default Re: Where to set Focus?

    I use a bright star to focus in BYEOS liveview, then confirm with a Bahtinov Mask---it's always been right-on. For me, BYEOS has always been accurate.

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    Default Re: Where to set Focus?

    There's not much point in using a Bahtinov mask on a fuzzy target. Use either a Bahtinov mask or BYEOS with live view to focus on a bright star. Then slew to the target.

    If you are concerned about framing the target without using an eyepiece, find it first with an eyepiece and frame it the way you want. Do a 'sync' (terminology varies with different goto systems) so that the exact coordinates are recorded in the goto system. Then slew away to a bright star. Mount the camera and focus it. Then slew back to the target. Having the exact coordinates recorded in the goto will ensure that it reproduces your framing.
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    Default Re: Where to set Focus?

    Quote Originally Posted by s24man View Post
    Use your mask to focus on a bright star, and then slew to your target.
    Quote Originally Posted by jforkner View Post
    I use a bright star to focus in BYEOS liveview, then confirm with a Bahtinov Mask---it's always been right-on. For me, BYEOS has always been accurate.

    Jack
    Quote Originally Posted by KeithBC View Post
    There's not much point in using a Bahtinov mask on a fuzzy target. Use either a Bahtinov mask or BYEOS with live view to focus on a bright star. Then slew to the target.

    If you are concerned about framing the target without using an eyepiece, find it first with an eyepiece and frame it the way you want. Do a 'sync' (terminology varies with different goto systems) so that the exact coordinates are recorded in the goto system. Then slew away to a bright star. Mount the camera and focus it. Then slew back to the target. Having the exact coordinates recorded in the goto will ensure that it reproduces your framing.
    Thanks everyone! That all makes perfect sense.
    OTAs: Explore Scientific ED80 Essential Edition / The Little Guy (Celestron 90SLT) | Mount: Celestron Advanced VX | Gear: Canon 70D / Hutech LPS-D1-48 / ES 2" Field Flattener / QHY PoleMaster / Celestron GPS / ZWO ASI120MC / Orion 50mm Guide Scope
    Software: BackyardEOS Premium / PI / CPWI / Stellarium/StellariumScope / PHD2 / RegiStax 6 / AutoStakkert!2 / PIPP
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