Stellarvue SV90T Apo Triplet
The Stellarvue SV90T features a 90mm f-7 (630 mm focal length) objective lens with an Ohara FPL53 center element. This provides premium quality visuals and photographs, as numerous images posted on the internet can confirm. This telescope is well suited for astrophotography with chips that are APS sized or smaller. For the largest chip cameras, theSV90TF is recommended.
Fully multicoated apo triplet objective
The high Strehl, apochromatic triplet objective provides extremely high contrast, and several extreme broadband coatings are used on all six lens.
This boosts contrast
The stars appear vivid and the background, velvet black. These coatings transmit light above and below the visual spectrum, which is important to minimize reflections seen on ccd images.
White aluminum tube and dew shield
The aluminum tube and dew shield are machined and painted white. The fittings are black anodized aluminum. The dew shield retracts reducing the length of the telescope when being stored; it extends to minimize dewing of the objective at night and serves as a glare shade during the daytime.
Internal tube treatment
The inside of the tube assembly is painted "ultra flat black" and is fully baffled to eliminate reflection. The focuser has 11 baffle ridges to reduce drawtube reflections. These ridges are painted, reducing the most commonly found type of reflected glare. This treatment provides better glare reduction than focusers that only have the ridging to prevent glare. All of these methods add up to provide the outstanding contrast of the Apo triplet lens.
Dual speed Crayford focuser with precision bearings
The 2" Crayford focuser uses a compression ring and three thumb screws to secure accessories and cameras firmly in place. A compression ring 1.25" adapter with 2" filter thread is also provided. The focuser has three focusing knobs, one on the left and two on the right.
The single knob on the left and a larger knob on the right provide coarse focusing. On the right side is a second, slightly smaller, brass colored fine focus knob. This fine focus knob has an 11-1 rotation reducer, allowing for extremely fine focusing. The reducer in the Stellarvue focuser uses a hardened stainless shaft and precision ball bearings. It has greater longevity than some competitive dual speed focusers.
A tension adjustment set screw is positioned under the focuser and a thumb screw allows for locking the focuser when engaged in astrophotography. The drawtube is inscribed with a millimeter scale on top. Two 5 mm threaded holes on top of the focuser allow for the attachment of two separate finder scopes. One may also mount finder scopes and accessories to the clamshell mounting ring. The focuser is fully rotating. To rotate the focuser, simply loosen the rotation knob.
Machined aluminum clamshell mounting ring with Vixen Dovetail
The Stellarvue SV90T Apo Triplet uses the unique, American made, precision CNC (computer numeric controlled) machined aluminum mounting ring. This clamshell ring has several 10/32 threaded holes on the side and top to accommodate a finder scope, a guide scope or another accessory. The clamshell is precision machined and has an "easy-one-touch," single knurled knob for tightening and loosening the ring.
This allows fast and convenient balancing of the telescope tube. The underside of the mounting ring has a Vixen style dovetail rail with safety grooves. This rail fits most telescope mounts on the market such as the Vixen, Celestron CG5 or Meade LXD-55. If you plan to mount this telescope on a larger mount that uses the Losmandy rail our TP6 (Losmandy sized) plate attaches to the bottom of the Vixen rail with two screws.
Return From Stellarvue SV90T Apo Triplet To Stellarvue TelescopesTelescopes Home Page