Description
Vixen's standard "photo-visual" SD apochromatic refractor with a focal length of 625mm.
Vixen SD apochromatic refractors feature "Super extra-low Dispersion" optical glass in its objective lens. With the use of an SD reducer HD kit or SD Flattener HD kit, the image circle of 44 mm in diameter is obtained to be used for photography with DSLR cameras with a full-frame imaging sensor.
-
Vixen Telescope SD81S Optical Tube Assembly Description
-
The SD lens suppresses residual chromatic aberration far below the threshold of visibility.
A lens of refracting telescopes has chromatic aberration which is caused by different wavelengths of visible light (colors) focusing at different distances. The Vixen SD lenses, made of FPL53 super extra-low dispersion glass, allow for correcting the chromatic aberration over a wide spectrum of light. The SD lenses focus visible rays of light from the Cray(red), d-ray(yellow), e-ray(green), F-ray(blue) to X-ray(violet) at nearly the very same position. As shown in the diagrams of spherical aberration, it verifies that the chromatic aberration is highly corrected over a wide spectrum of light with the SD lenses. Especially the g-ray, which affects image contrast, is suppressed excellently. The SD81S delivers outstandingly sharp images with high contrast for both visual and photographic applications. Brighter F7.7 images will satisfy the most demanding visual astronomer or astrophotographer.
-
Optical tube of a moderate length for visual observation and astrophotography.
The optical tubes of the SD81S, SD103S, and SD115S are designed to be shortened to their length. It is convenient to carry and set up and balance the optical tube easier.
-
Quick change of viewing orientation with flip mirror
The provided Flip mirror allows you to change light passes for comfortable observing posture. With two eyepieces of different focal lengths attached to the flip mirror, you can switch magnifications quickly.
-
Versatile accessories for visual observation and astrophotography.
The focuser drawtube has 60mm threads in diameter for attaching a variety of optional eyepieces and accessories for visual and photographic purposes.
-
Optional accessories to expand your pleasure of astrophotography.
This kit consists of components for prime focus astrophotography with the SD81S, SD103S, or SD115S optical tube. This reducer is made to be used in combination with an accessory such as a wide photo adapter 60DX, sold separately.
Best selling alt-azimuth mount from beginners to professional
Featuring excellent rigidity, stability, and portability, the popular PORTA II alt-azimuth mount is chosen and used by a great number of users from amateur to professional.
Vixen Telescope PORTA II Alt-azimuth Mount (with tripod) Description
-
Slow-motion handles
The whole-circle slow-motion movement of the PORTA II provides smooth telescope operation at every pointing angle. Handle positions of both vertical and horizontal slow-motion controls can be altered in 45-degree increments. This allows a comfortable posture while using the slow-motion handles for various size optical tubes.
-
Dovetail-plate attachment
With Vixen's renowned dovetail-plate system, many optical tubes, up to 160mm in outer diameter, can easily be swapped on and off the mount.
-
Accessory tray
An accessory tray holds small pieces such as a camera or eyepieces. Very useful when observing at night.
-
Compartment for tools
Slow-motion handle positions and the amount of friction on the axes are adjusted with tools located in the compartment under the rubber covering. You will always have your tools available.
-
Detachable tripod system
The mount head and tripod are detachable by a single fixing bolt which makes it convenient for transport and storage.
-
Friction control system
The optical tube can be moved freely by hand and the friction holds its position anywhere you stop it. It allows you to manually point the telescope at target celestial objects you wish to view.
Specifications
SD81S Optical Tube Assembly
-
The objective lens, the effective aperture81mm SD apochromatic, multicoated
-
Focal length625mm
-
Focal ratioF7.7
-
Resolving power1.43 arc seconds
-
Limiting magnitude11.3
-
Light gathering power134×unaided eye
-
Focusing mechanismRack-and-pinion, with lock knob
-
FinderscopeXY Red dot finder II (1×aimimg device)
-
Adapter thread / Visual back60mm and 42mm for T-ring / 50.8mm and 31.7mm push-fit with a flip mirror diagonal
-
AccessoriesTube rings, Dovetail tube plate, Metal carry handle
-
PhotographyUsable with Prime focus, Eyepiece projection, and Afocal imaging
-
Solar observationAvailable with Sun projection screen set B
-
Dimensions / weight90mm dia. and 585mm long / 3.6kg (Net 2.3kg)
Accessories
- Flip Mirror Diagonal
- Dovetail Tube Plate
- 7×50mm with a dark-field illuminated reticle
- 50mm XY Finder Bracket II
Delivery Content- SD81S Telescope
- Eyepiece SLV 6mm (104x)
- Eyepiece SLV 20mm (32x)
- Tube Rings
- Flip-Mirror
- Folding mirror, carry handle
- Dovetail Bar
- Porta II Azimuth Mount/Tripod
- Total weight 9.5kg
Specifications
PORTA II alt-azimuth mount
-
Mount typePORTA II alt-azimuth mount
-
Vertical and horizontal slow motionsWorm and wheel gears with 120-tooth whole-circle movement, with slow-motion handles
-
Optical tube setting upDovetail-plate attachment system
-
Maximum loading capacityApprox. 5kg
-
Weight5.7kg including tripod
-
Tripod typeAluminum 3-sectional legs (with tray)
-
Tripod dimensionsL: 900mm⇔1,300mm, H: 705⇔1,200mm, Radius: 370⇔606mm
-
