Uploaded November 2024 | Updated September 2026, 5 days ago
Schmidt-Cassegrain telescopes, or SCTs, have focal lengths far greater than the actual physical length of the telescope. As an example, one of the most famous SCTs, the Celestron C8, has a focal length five times longer than its optical tube. How does the SCT appear to pull focal length out of thin air?
See a demonstration of focal length and inversion at the Physics Demo channel:
Concave Mirror Demo: youtu.be/7zv-4Zh-9R4?si=zSyUaJoRcZwbivye
Concave Mirror Demo--Pendulum: youtu.be/3e-LZPHBA2M?si=QTexhIzM_BQHgoZt
View the ongoing Horsehead Nebula Project: astrobin.com/fbm30x/D
*** *** ***
Check out a portfolio of astro imagery shot from the Sky Story Observatory at Astrobin: astrobin.com/users/SkyStory
We are Telescope Canada's first affiliate. It's a great place for astrophotography gear with fast service and an informed staff who are passionate about astrophotography. Using the following link adds nothing to your cost but helps us produce more educational videos about this amazing universe around us. Just copy and paste the link into your browser: https://telescopescanada.ca?bg_ref=KK15sLXmWw
All videos best viewed in 4K.
Peer into the cosmos on Sky Story and along the way come to appreciate our world all the more. Here, we explore the realm of nature beyond our Earth through the fields of astronomy and astrophotography.
All our programs are committed to the standards of scientifically accurate, high quality content that aims to educate and inspire. New videos are posted weekly, so please subscribe.
#astronomy #astrophotography #space #nebula #stars
Schmidt-Cassegrain telescopes, or SCTs, have focal lengths far greater than the actual physical length of the telescope. As an example, one of the most famous SCTs, the Celestron C8, has a focal length five times longer than its optical tube. How does the SCT appear to pull focal length out of thin air?
See a demonstration of focal length and inversion at the Physics Demo channel:
Concave Mirror Demo: youtu.be/7zv-4Zh-9R4?si=zSyUaJoRcZwbivye
Concave Mirror Demo--Pendulum: youtu.be/3e-LZPHBA2M?si=QTexhIzM_BQHgoZt
View the ongoing Horsehead Nebula Project: astrobin.com/fbm30x/D
*** *** ***
Check out a portfolio of astro imagery shot from the Sky Story Observatory at Astrobin: astrobin.com/users/SkyStory
We are Telescope Canada's first affiliate. It's a great place for astrophotography gear with fast service and an informed staff who are passionate about astrophotography. Using the following link adds nothing to your cost but helps us produce more educational videos about this amazing universe around us. Just copy and paste the link into your browser: https://telescopescanada.ca?bg_ref=KK15sLXmWw
All videos best viewed in 4K.
Peer into the cosmos on Sky Story and along the way come to appreciate our world all the more. Here, we explore the realm of nature beyond our Earth through the fields of astronomy and astrophotography.
All our programs are committed to the standards of scientifically accurate, high quality content that aims to educate and inspire. New videos are posted weekly, so please subscribe.
#astronomy #astrophotography #space #nebula #stars
