Cloud Break Optics

Optiques Fullum Folded Newtonian 65" f/3.5

Optiques Fullum Folded Newtonian 65" f/3.5 - Main image
$536250 $715000 In stock

Category: Reflecting Dobsonian

As these are custom-made systems, please contact us to discuss your requirements. Final price can vary depending on your custom requirements.
The price does not include crating and shipping.

Description

Explore Scientific is proud to partner with Optiques Fullum to offer the full range of large Fullum-folded Newtonians for the discerning astronomer who demands exceptional quality, ease of use and extreme apertures.

Fullum-folded Newtonian telescope systems are designed, engineered and manufactured in-house by Optiques Fullum and are available with mirrors up to 65" (165 cm) in diameter.

This configuration features a parabolic primary mirror with a very short focal ratio (between f/3.5 and f/4), coupled to a secondary mirror placed much lower than normal, which will redirect the optical axis at a 17.5-degree angle instead of 45 degrees. This results in a more secure focal position for the observer.

For these telescopes, Optiques Fullum fabricates very light custom-designed aluminum and composite structures, fully motorized with a precision GOTO tracking system.

Optiques Fullum's unique Techno-Fusion mirror design produces fast cooling mirrors. Never worry about cool-down time and heat plumes again! Another benefit of Techno-Fusion comes from its light-weighting and its unmatched rigidity through a fused structure. You will never find yourself the victim of problems found in large solid mirrors such as astigmatism or other self-deflection aberrations.

At the end of the day, your large primary mirror is the heart of your telescope. At Fullum Optics, they make sure that it’s ready for its mission which is delivering the universe to your eyes without worrying about thermals or flexion.

All mirrors are manufactured according to the highest standards of conical constant accuracy, surface roughness, and critical tolerance specifications.

As these are specialized telescopes that are built to order, every aspect of the system is customized to the exact requirements of the client, be it for visual observation, research, or imaging. The price does not include shipping.

CA Residents: Prop 65 WARNING(S)

Specifications

Optical design Newtonian reflector
Objective diameter 1651 mm
Focal length 5778 mm
Focal ratio f/3.5
Resolving power 0.07 arc second
Stellar limiting magnitude 18.79
Max. magnification 4127 x (theoretical)
Light gathering power 55,629 times the human eye
SKU OF-65F3.5 FOLDED
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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.6 / 5 · 5 reviews)

Aurora ★★★★★

Had to reach out about my specific setup, but the team was incredibly helpful in tailoring the folded Newtonian design to my needs. The 65" f/3.5 focal ratio gives incredibly crisp views of deep-sky objects even from my light-polluted backyard.

Julian T. ★★★★★

I was a bit nervous about the custom ordering process, but the team was incredibly responsive and helped me dial in exactly what I needed for my deep-sky imaging setup. The folded optical design keeps the tube length manageable for such a massive aperture, which is a huge plus for my cramped observa

Samuel ★★★★★

Even with the large 65" aperture, the folded design makes it surprisingly manageable to move around the yard. The custom build process was smooth, and the final price was exactly what we discussed. Views of the Veil Nebula through this f/3.5 system are breathtaking.