TRI-FOCUS offers THREE independent, knob controlled, focusing ratios - micro, median & macro.
GLIDERS unique CRAYFORD design is the most stable and silky-smooth on the market, by a factor of 10!
MasterGlide focusers can handle leveraged imaging train loads that others only dream of (20 lbs with ease).
Our exclusive QUAD-LOCK system secures your 2" barrel nose into the moving tube like a ROCK.
All MasterGlide focusers have GIANT 1" diameter BALL BEARINGS for ROCK-SOLID operation.
All MasterGlide focusers have 3/8" thick-wall, solid 6061 alum. housings & moving tubes. NO other focuser even comes close.
MasterGlide focusers are LARGE focusers, so they won't even fit 8" SCTs. They're ONLY for 10" and larger SCTs.
MasterGlide focusers screw DIRECTLY onto your 3.25" large format visual back - NO FLEXURE!
The ONLY focuser that accepts your FOCAL REDUCER (FR) inside it's moving tube, effectively reducing your FR's profile to ZERO.
10 MasterGlide models to suit any budget or application. Need more proof? See "Unsolicited User Comments" link.
Best of all, VSI Focusers are [only] sold directly from the manufacturer to you, the customer, so prices are always WHOLESALE.
Still not convinced? Then go buy the other focusers and learn this expensive lesson the hard way.
NEW TRI-FOCUS micro (ultra-fine) offers tangent arm manual micro-focusing for astroimaging
NEW TRI-FOCUS median offers spur-gear reduced manual focusing between micro and macro
NEW TRI-FOCUS macro offers direct, super-smooth manual focusing that other focusers call "fine"
NEW 4" dia. SPINNER knobs increase control, resolution & sensitivity by a factor of 4
NEW dual pressure point Crayford focusing mechanism
NEW 200 precision cut locking splines on the internal moving tube
NEW QUAD-LOCK system to secure your 2" barrel nose in the focuser's moving tube
NEW proprietary rotating barrel [Quad] locks for our NEW Hexagonals (see link for details)
NEW narrower gap between housing and moving tube - only 0.025" (1/40th of an inch)
NEW more durable "Glass-Bead" super finish - looks new longer!
NEW engineered weight reduction machining without sacrificing rigidity
NEW focusing tube locking thumb screw repositioned to improve holding power
NEW ultra-precision digital machining guarantees perfect fit on every Glider part
*Replaces the former, discontinued MONSTER focusers
AP, Borg, OGS, RC Optical, Takahashi, etc., etc. - Just Call VSI
For 10" and larger Meade/Celestron SCTs, or custom mounted to any scope
3.25"-16tpi threaded base for large format SCT docking
Refractor/Newt/Dob Docking Ring Converters install Gliders on any scope
Custom machined docking available (see Custom Machining link for details)
Exclusive focal reducer "Hidden Cavity" on all models - zero-profile focal reducers!
Guaranteed zero image shift at any load factor
Solid brass vibration dampening arm assemblies
Exclusive Zenith Lift System, all models (VSI trademark, patented)
Adjustable focusing tension
Tangent arm micro-focusing control (M2, 3, 4, 5)
Four 1" diameter precision ball bearings
Double #10-32tpi extended Nylon equipment locking thumb screws
Thick-wall construction (0.375" approx.)
Tri-Focus macro focusing knob resolution: 1 rev. = 0.47" of tube travel
Tri-Focus median focusing knob res. (M2, 3, 4, 5): 1 rev. = 0.16" of tube travel
Tri-Focus micro focusing knob res. (M2, 3, 4, 5): 1 rev.=0.005" tube travel
Tri-Focus macro focusing knob max. turns: 2 turns = 1.0" of tube travel
Tri-Focus median focusing knob max. turns: 6 turns = 1.0" of tube travel
Tri-Focus micro focusing knob max. turns (M2, 3, 4 , 5): 10 turns=0.05" tube travel
Overall focusing tube travel = 1" (2 to 6" custom tube travel available)
2.5" minimum profile (M1, 2, 3)
Over 20 lb. imaging train loads
Docking: 3.25"-16tpi Meade SCT
Adapter required for Meade 16" & Celestron SCTs, see Docking Converters link
MasterGlide focusers are not compatable with 8" SCTs, see MicroGlide Focusers link
Weight: less than 2 lbs. (approx.)
Various GLIDER aspects and features are PATENTED
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