Cloud Break Optics

Optiques Fullum Folded Newtonian 55" f/3.5

Optiques Fullum Folded Newtonian 55" f/3.5 - Main image
$281050 $385000 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 spot 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 1397 mm
Focal length 4889 mm
Focal ratio f/3.5
Resolving power 0.08 arc second
Stellar limiting magnitude 18.43
Max. magnification 3492 x (theoretical)
Light gathering power 39,828 times the human eye
SKU OF-55F3.5 FOLDED
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Express Shipping · United States: $3.99

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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)

Eli ★★★★★

I was a little worried about the lead time for a custom build, but the final telescope is absolutely worth the wait. The f/3.5 focal ratio gathers light incredibly well, and the views of the Orion Nebula were breathtaking from my backyard.

Amelia I. ★★★★★

The collimation holds rock-solid even after transporting it in my trunk to a dark site, and the views of M13 through that 55" mirror are breathtaking. I was worried about the cool-down time with such a large mirror, but it stabilizes in under an hour.

Mia ★★★★★

Ordering was a bit of a process since it's custom, but the folded Newtonian design is incredibly compact for a 55-inch focal length. I set it up in my backyard and the views of the moon were sharp and bright, just what I hoped for. For a dobby this size, it's surprisingly easy to transport.