Enjoy your 2" eyepieces for viewing of deep sky objects at night or
for terrestrial objects during the daytime with this Baader 2" 90 Degree
Amici Prism Erecting Diagonal. This diagonal comes with a 2" barrel,
which fits into 2" focusers, and can either accept 2" eyepieces or 1.25"
eyepieces when used with the included adapter.
The Amici Prism has long been favored as the best choice for
producing correctly oriented images in refractors and cassegrain type
telescopes. However, the production of an amici prism is complex and
requires a much higher level of quality than a standard mirror or right
angle prism diagonal. Prism faces must be polished smooth, flat, and
very accurately located at the proper positions and angles. The sharp
roof edge must be made vanishingly fine. These demands on prism quality
are the prime reason why even expensive amici prism diagonals have
developed a deserved reputation for poor image quality. Even the
so-called premium quality amici prisms typically produce astigmatic or
asymetrical images and display a bright prominent central diffraction
spike (the roof edge diffraction spike in the Baader Amici is extremely
faint). Also, making matters worse, undersized prisms are used to save
cost and large housings give the false illusion of a large clear
aperture (as is the case with most so-called 2" amici star diagonals
Baader Planetarium produces what is perhaps the finest amici prism
star diagonal available today. The prism has been made to the proper
specifications, in order to provide image quality that suffers from none
of the defects found in commonly available correct image amici
diagonals. The finest 7-Layer Multi-Coatings ensure the image is bright
and contrasty. The precision machined aluminum housing provides a stress
free mounting and precise location for the prism, unlike the typical
weak plastic or crudely cast and machined housings found on lesser
diagonals. The end result is a correct image diagonal that is good
enough for more than just high-quality terrestrial viewing.
Correct image diagonals have been used traditionally for terrestrial
viewing, and limited to low (under 100X) magnifications. The high
quality of Baader's diagonal lets you use much higher magnifications
without aberrations or image breakdown for both astronomical and
terrestrial uses. The diagonal is perfect for matching astronomical
charts or sketching correctly oriented planetary detail. It also
functions well with the Baader Maxbright BinoViewer and Baader/Zeiss
Mark V BinoViewer, to provide correctly oriented binoviewing. Many users
have commented on how wonderful it is to enjoy correct-image views of
all planetary and deep sky objects, and that they would not go back to
traditional star diagonals. Finally, views that match star and lunar
Diagonal weight without 1.25" adapter = 16.2oz; weight with 1.25"
adapter = 19.1oz; 2" nosepiece is threaded to accept standard 2"
astronomy filters (M48x0.75); 2" eyepiece holder features a brass
compression ring, and it cannot be separated from main diagonal body.