Mastering Köhler Illumination: Setup, NA, and Contrast
Learn Köhler illumination fundamentals—how to align, set condenser and aperture NA, improve contrast and resolution, and troubleshoot common issues.
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Guides to help with your Stargazing Adventure

Information on Galaxies, Stars, Constellations, Planets, Moons, Comets and Asteroids
Listen to Bernard Miller describe his journey into AstroPhotography and detail how he captured this stunning image of the Sculptor Galaxy.
Read the full article here.
Drew Evans talks about his passion for astrophotography, the equipment used and tips for post processing image data.
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Hear D.j Van Bourgondien as he talks about using his Celestron EdgeHD 8″ telescope to capture this image of the Fireworks Galaxy
Read the full article here
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Below are a selection of our Articles, to find more click on one of the sections above, or use the Menu at the top of the page.
Learn Köhler illumination fundamentals—how to align, set condenser and aperture NA, improve contrast and resolution, and troubleshoot common issues.
What an 8-inch Dobsonian can reveal, how to set it up, choose eyepieces, collimate mirrors, and buy smart. A practical guide for clear, sharp views.
How to Observe the International Space Station (ISS) with a Telescope Observing the International Space Station (ISS) with a telescope is a thrilling experience for amateur astronomers and casual stargazers alike. As one of the largest man-made objects in low Earth orbit, the ISS is easily visible to the naked eye when conditions are right.