Omegon Apochromatic refractor Pro APO AP 80/500 ED Carbon OTA + Field Flattener

Carbon Fibre Tube

This apochromat is suitable for visual observing but was, in fact, developed especially for astrophotography. Use the advantages of a carbon fibre tube: it is particularly light and so is suitable for use on smaller mounts.

The carbon fibre tube also offers inherent stability and only minimal thermal expansion. These advantages are particularly useful for astrophotography, as the focus remains stable for the whole night. The dew shield is also carbon fibre and can be extended easily. In addition, the tube is lined with black felt. 

The Focuser

The telescope is equipped with a Crayford style focuser. It belongs to a new generation of drawtubes, which are patent pending. Absolute precision and enormous load bearing capacity are the main advantages of this focuser. It can carry accessories of even up to 10kg in weight by the use of an additional locking screw. Even under the application of extreme force, the drawtube will not move even by a millimetre: Once you have found focus, it will not change, even if you change location.

A 1:11 reduction ratio provides you with fine adjustment when focusing, allowing even more precision than with most telescopes. Do you use a full format chip for astrophotography, or do you intend doing this in the future? Even with full format cameras, images of objects are recorded free of vignetting. The complete focuser is freely rotatable: loosen the locking screw and the unit can be rotated through a full 360°. 

Carrying case included

The aluminium case provided is ideal for storing your valuable optics. Extremely robust, with carrying handles and metal fittings, it can withstand some shaking around with no problem. The interior features accurately cut out foam mouldings which keep the telescope tube in exactly the same condition as when you last stored it there.

The Omegon ED apo refractor has outstanding optics and high-quality mechanical components. This very special telescope provides astrophotographers, visual observers or nature watchers with a unique source of pleasure when observing starry skies or nature watching. Pin-sharp stars, right out to the edge of the field of view.

The apochromat doublet

TrueColor lens elements are built into the objective lens of Omegon ED apochromat doublets. The two element objective lens is constructed by a clever combination of OHARA FPL-53 and S-NBM51 glass. These are special types of ED glass with high and low refractive indices and superior light transmission characteristics. A particularly special feature is the use of S-NBM51 glass, which is usually employed in the optics of apochromatic fluorescence imaging microscopes. The benefit to you is that the optics provide a particularly sharp and high-contrast image!

Provides perfect image flatness for your astronomy photos

Many refractors and reflector telescopes suffer from field curvature. A curved image field means that stars at the edge of the field of view no longer appear as pin-sharp points but as out of focus discs. But now the new Omegon field flattener will conjure astronomy photos with pin-sharp stars right out to the outer edge of the image field.

Bringing the problem under control

Field curvature is a common optical defect that is not noticeable with visual observing or photography using small chips. If, however, you use a large chip or a full-frame camera, then this defect becomes glaringly obvious. Of course you could always crop your images to remove the blurred outer region; but using a field flattener it is much more elegant solution for using your expensive camera with its large format chip.

Flat field over the entire field of view

The field flattener gives you an absolutely flat image over the entire photographic field of view. Also, the focal length remains the same when using the flattener.

Suitable for telescopes from f4 to f8

You can use the Omegon field flattener with any refractor with a focal ratio between f4 and f8.

M48 thread for better aperture illumination

The Omegon field flattener has an M48 thread on both sides - giving you complete aperture illumination. A T2 thread plus M42 would limit the incoming light beam and so not provide sufficient aperture illumination for telescopes with 2" focusers. But using only the M48 thread, you make use of the entire light entering the telescope.

Use additional accessories - 109mm of back focus

This field flattener has a very generous 109mm of back focus. This means that you need a spacing of 109mm between the lens plane and the camera chip. This is an advantage, as it means you can use other accessories in between - such as a filter wheel, a flip-mirror or an off-axis guider. Using the correct extension rings will let you set the optimum spacing - whether you use accessories in between or not. 

The advantages in a nutshell:

• field flattener for refractors
• suitable for telescopes from f4 to f8
• M48 thread for complete aperture illumination at 2"
• room for accessories between - 109mm of back focus
• excellent multi-coating on lenses