Search results
Results from the WOW.Com Content Network
PLate OPtimizer, or PLOP is a CAD program used by amateur telescope makers to design primary mirror support cells for reflecting telescopes.It was developed by telescope maker David Lewis, first described in 1999, [1] and used to simplify calculations needed in the design of mirror support cells. [2]
The Schmidt camera is a wide-field photographic telescope, with the corrector plate at the center of curvature of the primary mirror, producing an image at a focus inside the tube assembly at the prime focus where a curved film plate or detector is mounted. The relatively thin and lightweight corrector allows Schmidt cameras to be constructed ...
The main tube of telescopic sights varies in size, material, the applied production process and surface finish. The typical outside diameters vary between 19.05 mm (0.75 in) and 40 mm (1.57 in), although 25.4 mm (1 in), 30 mm and recently 34 mm are by far the most common sizes.
Telecompressor or focal reducer: Optical element to decrease the telescope's focal length and magnification (usually by a fixed percentage) and widen the field of view, providing opposite effects of a Barlow lens. Star Diagonal: Used to change the angle of the light coming out of a telescope, for easier viewing.
The addition of a focusing lens reduces the light transmission of the optical system contained in the telescope tube somewhat. Internal focusing is generally considered the mechanically more robust central focusing solution and with the help of an appropriate seal like O-rings air and moisture ingress can be prevented, to make binoculars fully ...
Although speculum metal mirror reflecting telescopes could be built very large, such as William Herschel's 126-cm (49.5-inch) "40-foot telescope" of 1789 and Lord Rosse 183-cm (72-inch) mirror of his "Leviathan of Parsonstown" of 1845, impracticalities in using the metal made most astronomers prefer their smaller refracting telescope ...
Optical instruments like microscopes, telescopes, and DSLRs all have optical trains that guide the incoming light towards a detector or the eye of an observer. The optical train of a telescope is commonly called an optical tube assembly ( OTA ) or simply an optical tube .
Speculum mirrors tarnished rapidly; with two mirrors, one could be used in the telescope while the other was being re-polished. The telescope tube and supporting structure were completed in 1845. [2] A 1:24 model of the telescope made by Parsons in 1844-45. The mirror was 5 inches (13 cm) thick and weighed almost 3 tons.