TMB Optical Telescopes

More Information  · Recommended Accessories  · Images of Some Features Price $1,395.00 Shipping $24.95 Highest Useful Magnification 169x Visual Limiting Magnitude 12.0 Focal Length 504mm Focal Ratio f/6.3 Resolution 1.45 arc seconds Aperture 3.1" Net Weight 5.1 lbs. Warranty 2 years

• 80mm f/6.3 apochromatic triplet optics using FPL-53 ED glass
• a lightweight high-tech carbon fiber optical tube and dew shield
• 2" dual-speed FeatherTouch 2.5" travel Crayford focuser with internal brake
• 2" and 1.25" compression ring eyepiece holders
• retractable dew shield, dust covers, and hard case
• hinged split tube rings for use on a German equatorial mount

    The TMB-80CF Signature Series puts exceptionally high optical and mechanical quality into a high-tech carbon fiber package. It is ideal for the serious on-the-go observer who will accept nothing less than unsurpassed imaging and visual observing performance.

    The TMB-80 is an exceptional 15.25" long travel scope, as well as a superb grab-and-go scope for observing and imaging – both within the solar system and out to the furthest reaches of infinity. Its images of subtle low-contrast lunar and planetary details are razor-sharp, with realistic and highly saturated color. Those images are free from chromatic aberration of any type, thanks to the scope’s FPL-53 ED (Extra-low Dispersion glass) triplet optics. The latest antireflection multicoatings and knife-edge internal baffles assure the maximum image contrast possible. Image excellence is limited only by the seeing conditions, not by any aberration or short-coming in the telescope.

This Telescope’s Optical and Mechanical Systems . . .

• Apochromatic triplet ED refractor optics: 3.1" (80mm) aperture, 504mm focal length, f/6.3 triplet lens using an FPL-53 ED (Extra-low Dispersion) glass element for a sharp and flat field and images that are high in contrast and free from spurious color (chromatic aberration).

• Multicoated optics: Fully multicoated on all air-to-glass surfaces with the latest antireflection materials for exceptionally high light transmission and excellent contrast. Light transmission is so high that the optics seem virtually to disappear when viewed from head on.

• Internal light baffles: Contrast-enhancing knife-edge light baffles in the optical tube, dew shield, and focuser provide truly dark sky backgrounds and high terrestrial contrast. In addition, the edges of the objective lens are blackened to eliminate contrast-reducing stray internal reflections.

• Carbon fiber body and dew shield: The body and dew shield are made of a high strength and very lightweight woven carbon fiber cloth encapsulated in a transparent high gloss epoxy. It is non-dentable, virtually indestructible, and has excellent thermal characteristics. The use of a carbon fiber composite reduces the weight of the TMB-80CF to a mere 5.1 pounds, a full 1.4 lbs. less than its optically-identical aluminum tube brother, the TMB-80. And it does it with no loss of strength or rigidity. Carbon fiber composites are so strong that the new Boeing 787 Dreamliner passenger jet will use a wing and fuselage made entirely out of carbon fiber.
     : The herringbone weave of the carbon fiber cloth is easily seen through its clear epoxy coating. The narrow alternating light and dark stripes of the weave seem to reverse their shades from light to dark and back again as you move the tube. The carbon fiber cloth is laid down by hand during the manufacturing process, so a subtle seam along the length of the tube is sometimes visible where the edges of the herringbone weave cloth meet. The focuser and metal trim are black anodized.

• Retractable dew shield: The self-storing retractable carbon fiber dew shield slows the formation of dew on the lens in humid weather to extend your undisturbed observing time. It also improves the contrast, similar to the effect of the lens shade on a camera lens, when observing during the day or when there is excessive off-axis ambient light at night (the neighbor’s yard light, moonlight, etc.) The dew shield is lined with black felt to eliminate reflections and off-axis light for exceptional contrast. The tube measures a compact 15.25" long with the dew shield retracted (18.5" long with it extended). A lock knob built into the dew shield lets you lock the dew shield firmly in place so it can’t slip down while aiming at the zenith.
     : The dew shield is oversized, with a 124mm o.d. compared to the 80mm lens diameter and 90mm tube diameter. This assures that tube currents, which typically follow the walls of a telescope tube, will be out of the converging 80mm light path for the most part and will have only a minimal effect on your images as the TMB-80CF cools down to ambient temperature. You can begin serious observing sooner with the TMB-80CF than you can with an aluminum tube 80mm triplet with a conventional dew shield design.

• Dual-speed microfine 2" Feather Touch Crayford focuser with internal brake: The #2025 precision-made genuine Feather Touch 2.5" travel focuser from Starlight Instruments has dual-speed focusing. There are two coarse focusing knobs. The right knob also has a smaller concentric knob with a 10:1 reduction gear microfine focusing ratio. This provides exceptionally precise image control during very high magnification visual observing, and during critical 35mm or CCD imaging. All focus knobs are ribbed, so they are easy to operate, even while wearing gloves or mittens in cold weather. The focuser uses hardened stainless steel guides and bearing surfaces for consistently smooth operation and long life. Multiple internal baffles in the focuser drawtube assure high contrast.
      Because the focuser is so smooth in operation and moves so freely, it can only hold a limited amount of weight (generally a little more than 1 lb.) without drifting out of focus when the focuser drawtube is not horizontal and has a vertical component. The focuser therefore contains an adjustable tension internal brake system to allow astrophotography, or visual use with heavy eyepieces, without the possibility of focus shift.
      The brake consists of a lever arrangement internal to the pinion block. Adjusting the thumbscrew under the pinion block causes the lever to press a friction pad onto the pinion. This increases the torque needed to turn the focus knobs. If the thumbscrew is turned all the way in (about 1 to 1¼ turns), the pinion shaft and the drawtube are locked in position for long exposure astrophotography. Visually, partial tightening of the internal brake offers a virtually infinite range of braking force to accommodate various eyepiece weights.

• Compression ring eyepiece holders: The Feather Touch focuser drawtube ends in a 2" accessory holder that uses a non-marring soft brass compression ring to hold a 2" star diagonal and accessories in place. The compression ring won’t dimple the barrel of your star diagonal and accessories as an ordinary thumbscrew can. Also supplied is a 1.25" eyepiece adapter that slips into the 2" compression ring accessory holder to let you use a 1.25" star diagonal or image erecting diagonal. Like the 2" accessory holder on the focuser drawtube, the 1.25" adapter also uses a non-marring soft brass compression ring to hold 1.25" star diagonals and accessories in place.

• Tube rings: The TMB-80CF has a pair of split hinged tube rings with five 1/4"-20 thread holes drilled into the top and bottom of each. These allow you to install the scope on a Vixen-style or Losmandy-style dovetail plate or directly on your equatorial mount, as well as letting you install a dovetail accessory plate on the top of the scope body.

• Tube finish: The optical tube and dew shield are made of carbon fiber composite with a clear epoxy finish that shows the weave of the carbon fiber cloth that provides the tube with its exceptional strength. The focuser and trim components are made of stainless steel and black anodized aluminum, with a brass-look anodized fine focus knob. Hardware components are stainless steel. The lock knobs are satin-finished aluminum.

• Shipping/storage case: The TMB-80CF comes standard in a locking hard case with carry handle for transportation and general protection purposes. TMB Optical is one of the very few manufacturers to provide a case at no charge for protection during shipping and as a storage convenience when the scope is not in use. Unfortunately, FedEx, UPS, and the Postal Service are very good at treating packages roughly. Occasionally, your scope can arrive in perfect condition, but with the walls of the shipping case dented in transit from rough handling, or the aluminum frame sprung, rendering the appearance of the case less than pristine. Damage to the shipping case in such instances is not covered by warranty.

• Other supplied accessories: A slip-on metal dust cap is standard, as is a plastic seal for the 1.25" accessory adapter.

• Two year warranty: As an expression of the confidence TMB Optical has in the quality of their products, the TMB-80CF is protected by a two-year limited warranty against flaws in materials and workmanship (shipping case excluded).