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Altair Ascent 102ED F11 Doublet Refractor OTA

Altair Ascent 102ED F11 Doublet Refractor OTA
 Altair Ascent 102ED F11 Doublet Refractor OTAAltair Ascent 102ED F11 Doublet Refractor OTA 
Price:  £599.00(Inc. 20% VAT)Earn 599 Loyalty Points
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Model:  SWA102EDF11-OTA-ONLY
Brand:  Altair

2 Year Warranty On All New Items

The ASCENT 102mm F11 ED Doublet refractor is optimised for visual observation and imaging of solar system objects. An evolution of the well respected "Red Tube Classic" Starwave 102 Achromat, now with ED optics and better mechanics!
The result is improved colour correction and contrast. It a geared focuser replaces the original Crayford style focuser allowing for heavier accessories, and the tube can be broken down offering 270mm of backfocus for binoviewing, or your own custom modifications for solar viewing with a PST module.

The ASCENT 102mm F11 ED is particularly effective for visual observation of planets, the moon and double stars and it copes with turbulent air (seeing) extremely well due to it's long focal length. It is also a very capable solar imaging telescope (with the appropriate filter) for white light (with the Altair Solar Wedge), and of course Hydrogen Alpha. It is easy to focus due to the extended depth of field and gives extremely sharp images. The long focal ratio minimises eyepiece aberrations, resulting an extremely flat field of view. Binoviweing is easy - just detach the focuser and unscrew the mid-section, then screw the focuser back into the tube. No tools are required to break the scope down for travel!
ED optics with geared focuser!
The machined and powdercoated aluminium tube can be broken down into two parts for easier transport, binoviewing or solar PST Mods which require a shorter tube.
Proper Dual Speed Geared focuser with micro focusing (essential for fine detail).
The 2" pushfit adapter has 3x thumbscrews and a brass compression ring. Diagonal barrels aren't marred, eyepieces and binoviewers or heavy Ha solar filters are firmly held and aligned.
Flat field and superbly high contrast with easy focusing make this an ideal visual telescope.
What you get:

Starwave 102mm F11 ED Doublet Objective, with full multicoatings on all surfaces in a collimatable lens cell with QC serial number. Guaranteed to arrive in perfect collimation.
2.5" Dual Speed Geared focuser with 1:10 ratio fine-focusing knob.
Rear 2" pushfit adapter with 3x thumbscrews and inner compression ring.
2"-1.25" Push-Fit Adapter with non-marring brass compression ring.
Optional 9x50 finder with metal body and front focusing lens. Metal mounting stalk is able to attach direct to the optical tube (screws provided) or with the Altair Universal Quick Release Finder Bracket (code: UNIFBR-QRB). High quality 23mm wide field eyepiece with laser etched, independently focusing reticule. (Not the usual fare on finder scopes).
Front push-fit metal dust cap, rear plastic plug style dust cap.
Genuine CNC machined tube rings, fully adjustable for balance and rotation.
Metal dovetail plate so you can use the scope with just about any telescope mount including iOptron, Skywatcher.
Metal dewshield 200mm length, 121mm diameter, retractable, can be unscrewed for lens cleaning.
The optical tube is 100cm length and weighs about 4.6kg.
The removable Binoviewer section is 120mm length therefore total tube length is 88cm when removed.
Backfocus is 150mm from rear end of focuser to image plane. (270mm backfocus to the image plane if Binoviewer tube is removed).

The ED advantage. When compared to Achromatic refractors of similar size, length and focal ratio, the Starwave 102ED offers better geared mechanics for easier focusing, and truer colour rendition thanks to the ED optics. The Starwave 102 ED delivers a sharp "contrasty" image with good colour correction and tight star images. The 80mm aperture gathers about 63% more light than an 80mm refractor and the brighter image shows more detail. With a higher power eyepiece or Barlow lens, this telescope will show details withing the planetary disc of Jupiter, the Great Red Spot, cloud bands of different sizes and textures, as well as the four largest Galilean moons and their shadows cast on Jupiter. The contrast is very good enabling you to see a jovian moon against the brightly lit background of Jupiter. Saturn's rings and Cassini division are easy to see at higher magnifications and cloud bands are visible on Saturn as well as the polar caps. Mars shows surface features and polar caps easily. Thousands of craters are visible on the moon - enough for a lifetime of observation. Customers often reported the previous "Classic Red" Achromatic version of this telescope outperformed reflectors of 6 and 8" on planets and the moon in contrast and suble detail. The ED version improves on the "Classic Red" version both optically and mechanically with a modest price increase.
The convenience of a refractor. This is the perfect scope to take out and just observe with. It cools down fast thanks to the aluminium tube and long focal length doublet objective design. Unlike reflectors, the optics do not require frequent collimation (alignment) before use, so the product is virtually maintenance free aside from the usual yearly cleaning of the lens.
Daytime viewing. By adding an optional image-erecting prism diagonal, the Starwave 80 ED becomes a real performer when it comes to terrestrial and nautical observation, offering performance in the same category as ED spotting scopes costing many times the price. Simply increase the brightness on the Red Dot Finder and you can use the scope with pinpoint accuracy during daytime.

Mount choices: We recommend the Skywatcher EQ5 with motor drive for solar system imaging as a minimum, but the manual version of the EQ5 mount is more than adequate for visual planetary observation and you can add a motor drive later. If you prefer an electronic gadget-free experience, the Altair Sabre mount for visual observing, which requires no power. Please contact us for recommendations based on your intended observing style.

Astro imaging with the Starwave 102ED: A smooth dual speed "non-slip" 2.5" Geared focuser is supplied, with tension adjustment, able to carry a DSLR or CMOS camera such as the Altair Hypercam or GPCAM, and filter wheel if required. The optics are compatible with the Lightwave 0.8x field flattener / reducer. These are positioned at approx. 55mm from the rear flat face of the reducer/flattener to the camera sensor. The machined aluminium tube transmits heat to the optics, which benefits users of dew control systems. It also allows the optics to shed heat rapidly for fast cool-down to the ambient temperature - a must for best performance with any telescope.
Finder scopes and auto-guiding: You can attach the optional finder scope to easily locate astronomical objects. There are two ways to attach it. Firstly by means of the two screws provided and secondly by means of the Universal Quick Release Bracket (see options when ordering). The Altair 60mm Deluxe RACI Finder Scope is also compatible, and attaches to the focuser using the Universal Quick Release Finder Bracket.
Magnification: The magnification of a telescope is determined by dividing the telescope focal length in mm by the eyepiece focal length in mm.
For example the Starwave ASCENT 102ED has a 1122mm focal length, which, when used with the Altair Ultraflat 24mm eyepiece yields 47x magnification. (E.g. 1122mm divided by 24mm = 47x magnification). If you use a Barlow lens (such as the Altair 2x Flat Field Barlow) just multiply the magnification by 2x. In this case, the result is 94x.
Here's a table with Altair Ultraflat and Planetary eyepiece focal lengths, and the resulting magnifications with the Starwave 102EDF11:

Finding objects in the telescope. Using a low power eyepiece at around 25x you can quite easily spot a bright or large object by sighting along the telescope, however fainter and smaller objects would benefit from the optional "finder scope" accessory.
For imaging with your DSLR, you'll need a 50mm M48 Extension Tube and M48 DSLR adapter to insert into the 2" focuser aperture.

For imaging with the Altair Hypercam or GPCAM cameras, you can attach a camera or filter wheel by means of the rear 2" "push-fit" visual back (which has 3x thumbscrews for extra tight grip and zero flex).

Starwave ASCENT 102ED F11 technical specifications:
Optical Design: Fully Multicoated ED Doublet lens in collimatable cell
Aperture (mm): 102 mm (4")
Focal Length: 1122 mm
Focal Ratio: F11 (F8.8 with 0.8x reducer)
Optional Finderscope: 9x50 focusing objective (206.6mm focal length). Finderscope Eyepiece: 23mm focal length with laser etched reticule, independent focusing for eyeglass users.
Highest Useful Magnification: 200 x
Limiting Stellar Magnitude: 13
Resolution (Dawes): 1.14 arc seconds
Light Gathering Power (Compared to human eye): 212 x approx. (7mm pupil)
Optical Tube Length: 100cm / I metre
Optical Tube Weight: 4.6kg Approx.

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