Tilt needed on a front ERF?

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Tilt needed on a front ERF?

Post by AndiesHandyHandies » Fri Apr 12, 2019 3:59 pm


I am mounting a front 100mm aperture ERF on a 110mm aperture F9.4 telescope 1035mm Focal Length telescope, stopped to about F10 by moved forward collimator lens, which is a PST Mod.

How much do I need to tilt the ERF? Does the reflection need to be outside the focal plane image or some point in front, the position of the PST collimator lens or its original position where the holder is acting as a baffle?


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Re: Tilt needed on a front ERF?

Post by Merlin66 » Fri Apr 12, 2019 11:57 pm

I mount the D-ERF with a 1 -1.5mm tilt.
That's usually enough to prevent issues.....

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Re: Tilt needed on a front ERF?

Post by Bob Yoesle » Sat Apr 13, 2019 1:11 am

I recall the general parameter for both external and internal filter tilts is about 2 degrees.

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