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Model: catseye_teletube_xlsPart Number: catseye_teletube_xlsBrand: Catseye
Catseye premium quality Teletube XLS 2" sight tube suitable for f/3.0 - f/5.0 telescopes.
Larger-aperture, low f-ratio Newtonian telescopes with larger diagonal mirrors are becoming the norm, and the need for a precision 2" Sight Tube for properly positioning the Secondary beneath the focuser is a given. The Catseye line of "telescoping" sight tubes feature tuneable "length" capability to obtain the optimum tube-opening/Secondary "gap" resolution for insuring symmetrical intercept of the Primary light cone for maximum FOV illumination and contrast while maintaining axial registration via flush shoulder contact with the focuser draw-tube lip.
For Newtonian's with f-ratio's under f/4.7, the shorter "XLS" model (f/3.0 to f/5.0) is recommended for "seeing" that generous "oversized" Secondary (typical of imaging astrographs).
My secondary is 110mm on my big dob. With a Cheshire I could not see the whole secondary. This 2" sight tube solved the issue for me.
First Light Optics LtdUnit 7 Budlake UnitsBudlake RoadMarsh Barton Trading EstateExeter, DevonEX2 8PY
Company No. 5892293VAT No. 907 2895 01
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