Telescope common aperture size comparison chart
Jan 8, 2019 · Page 1 of 2 - Telescope common aperture size comparison chart - posted in Beginners Forum (No Astrophotography): Since there is usually a lot of talk about telescope aperture sizes and how much light gathering power they have, I decided to do a proper graphic, that contains basic info on most common aperture sizes and their light gathering area. For …
Aperture - reducing chromatic aberrations for achromat
Jun 10, 2022 · In my case, for high power targets, a 60 mm aperture give a much sharper image than 102 mm witch CA. This observing on the planets, the Moon, and countless doubles. I have a slower refractor for when I want the use of all 102 mm of aperture but the very small, f/4.5 refractor converted to an f/7.65 with mask is a great travel scope.
Maksutovs - Effective Aperture - Cats & Casses - Cloudy Nights
Jan 20, 2015 · Page 1 of 2 - Maksutovs - Effective Aperture - posted in Cats & Casses: Hi Folks, I recently read an excellent review (by Astrobaby) of the Skywatcher 180 Maksutov and I was intrigued to read that the effective aperture of this scope is actually around 170mm rather than 180mm, due to the fact that the main mirror is the same size as the corrector. I appreciate that …
4" vs 5" vs 6" - Refractors - Cloudy Nights
Sep 27, 2015 · Page 1 of 5 - 4" vs 5" vs 6" - posted in Refractors : Sometimes curious others ask what the differences are between different aperture refractors. Sometimes you will hear the jump in aperture from X to X is little or significant, but why do you always hear conflicting opinions? For example some people think the jump from 4 to 5 is more than the jump from 5 to 6 and vice …
Giant Binoculars: The New Explore Scientific BT-120
May 5, 2021 · Looking down the barrels of the double 120mm aperture, f/5.5 focal length tubes. Credit: Explore Scientific. Two eyes are always better than one. For years, we’ve espoused the virtues of using binoculars, as an intermediary between naked eye observing and learning the sky, versus a telescope.
Aperture ratio as a solid angle - Cloudy Nights
May 8, 2013 · Page 1 of 2 - Aperture ratio as a solid angle - posted in General Observing and Astronomy: When calculating the speed of an optical system, we use the focal ratio, or f/ratio, as the diameter of the aperture to its focal length. For example, a 100mm aperture and 500mm focal length is an f/ratio of 500 / 100 = 5.Image surface brightness at the focal surface scales as the …
Comparisons with 3.5" and 5 Inch Aperture - Cloudy Nights
Jun 5, 2019 · Comparisons with 3.5" and 5 Inch Aperture - posted in Questar Forum: Recently I picked up a nice C5 (XLT 127) SCT ota second hand on a local auction site. I have been using this wee telescope with a cheap star discovery mount and using the GOTO function to hop around DSOs from city and darker skies. Why I am posting this is this wee telescope to all intents and …
Review of Explore Scientific ED127 APO Refractor
Nov 22, 2012 · The f/7.5 focal ratio yields a compact tube, just 32” long (without the dew shield), including the focuser. The finder is real gem—erect images, very sharp and clear, with an illuminated reticle. In many ways the 127mm aperture is a perfect compromise, especially for city and close-in suburban locations.
Large Aperture Observations - Page 3 - Cloudy Nights
Oct 6, 2024 · Page 3 of 4 - Large Aperture Observations - posted in General Observing and Astronomy: For many years, I would observe with my 101mm Tele Vue refractor at dark sites, often with my 10 or 12.5 Dobs as well, and sometimes with an observing buddy and his 14.5 Starmaster Dob, then 20 Starmaster Dob, and finally 24 Starmaster Dob. Over the years, Ive …
Aperture Comparision - Optical Theory - Articles - Cloudy Nights
May 16, 2009 · Aperture Comparison. Jared Willson. Background: A question that frequently comes up on this and several other forums is how the relative sizes and designs of telescopes compare in terms of both deep sky performance and planetary performance. Is a 5" refractor comparable to an 8" SCT? Or a 6" Newtonian? Which is better for binary stars?