Köhler Illumination: Principles and Ray Paths
Understand Köhler illumination: conjugate planes, aperture vs field diaphragms, illumination NA, and trade-offs for uniform, high-contrast brightfield microscopy.
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Listen to Bernard Miller describe his journey into AstroPhotography and detail how he captured this stunning image of the Sculptor Galaxy.
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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
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Understand Köhler illumination: conjugate planes, aperture vs field diaphragms, illumination NA, and trade-offs for uniform, high-contrast brightfield microscopy.
Telescope Rental Options in the UK, USA, Canada, and Australia Stargazing and astrophotography are fantastic ways to explore the night sky, but purchasing a high-quality telescope can be a significant investment. If you’re new to astronomy or simply want to try different equipment without the upfront cost, renting a telescope can be an ideal solution.

12×25 Binos: What to Expect Binoculars are one of the most important assets in an amateur astronomer’s arsenal. They provide easy grab-and-go portability while allowing you to crank up the power and light gathering on objects that may need it. For daytime users, binoculars can also be a great tool for walking or exploring, providing