Cloud Break Optics

Optiques Fullum Folded Newtonian 40" f/3.5

Optiques Fullum Folded Newtonian 40" f/3.5 - Main image
$118800 $165000 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 1016 mm
Focal length 3556 mm
Focal ratio f/3.5
Resolving power 0.11 arc second
Stellar limiting magnitude 17.73
Max. magnification 2540 x (theoretical)
Light gathering power 21,066 times the human eye
SKU OF-40F3.5 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)

Madison ★★★★★

The folded design makes this 40-inch scope surprisingly manageable to set up, and the f/3.5 focal ratio delivers incredibly wide, sharp views of the Milky Way. I've spent hours just scanning the Cygnus region without needing to nudge the tube. Customizing the specs through the consultation was strai

Elizabeth T. ★★★★★

The mirror's f/3.5 speed really pulls in faint nebulae during my dark-sky sessions, and the custom folding mechanism makes transport to my observing site a breeze. I had to wait for the build, but the craftsmanship on the truss structure is absolutely worth it.

Ryan D. ★★★★★

I was worried about shipping a custom telescope, but the 20" mirror arrived perfectly collimated and the dual-speed focuser glides like butter. Tight tolerances all around.