Tak-106, AP900GTO, Unitrons, Masuyamas
The optimist thinks this is the best of all possible worlds. The pessimist fears it is true. "J. Robert Oppenheimer"
Telescopes are instruments of hope and faith. Hope that a better, clearer and brighter universe can be observed. Faith that we can bring these discoveries back to our small planet and create positive changes for all of it's inhabitants.
"The White Zone is for loading or unloading of passengers only. No Astrophotography." Cosmic Acres! Greatest restoration challenge: Tulley and Sons 3" achromat on Altazimuth mount, circa ~late 1820s
Classic refractors incl. Unitrons, Zeiss, Goto Optical, Royal Astro, Edmund; visual observer.
"Toto, I have a feeling we're not in Kansas anymore!"
Orange Tube C8, Tasco 7te-5, 4" Criterion Dynascope, Jason/Towa 313
Nikon Action Extreme & Pentax WPii Binoculars
At my club, everything one could want up to 18"
Quote:What bends the light inside those tubes, prisms or mirrors?
Quote:Quote:What bends the light inside those tubes, prisms or mirrors? Hi Joe, it has two first surface mirrors inside, a small 36mm diameter one up by the objective and a 60mm diameter mirror at the focuser end.
Quote:Quote:Quote:What bends the light inside those tubes, prisms or mirrors? Hi Joe, it has two first surface mirrors inside, a small 36mm diameter one up by the objective and a 60mm diameter mirror at the focuser end. Took a moment to follow that. The light path is folded. The point is that the larger mirror must be nearer to the objective, and the smaller mirror nearer to the focuser, at least viewed in relation to the direction of photons in the visible spectrum flying along the scope's light cone. They enter a 3" aperture, bounce off the large mirror, then the small mirror, then exit the still smaller eyepiece. If we excited the photons into X-rays so they could pass through the walls, then, sure; due to the folding, the small mirror would be near the objective, and the large mirror near the focuser, but that's not how visible-light photons in the tube see it.
Old brass and old glass
Cave - 1976 10" Custom Deluxe, 1977 8" Light Weight Deluxe, 1955 6" f/4 RFT
Unitron - 155C, 1960 142, 70's 128, 1954 128, 1960 114
Swift 1962 831
Monolux 60mm altz
Refractors Reflectors Two Cats A few eyepieces
Arcturus Observatory Belgium