Microscope Objectives: NA, Corrections, and Selection
Understand microscope objective lenses: optical corrections, numerical aperture, resolution, immersion media, coverslips, working distance, and how to choose the right lens.
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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 microscope objective lenses: optical corrections, numerical aperture, resolution, immersion media, coverslips, working distance, and how to choose the right lens.

Located on the ecliptic, Cancer (the “crab”) is one of the twelve constellations of the zodiac and is found in the northern celestial hemisphere. Cancer is a medium-sized constellation with an area of 506 square degrees and is home to many exciting deep-sky objects, many of which will be discussed in this ultimate guide to
What is dark matter? Explore the strongest evidence, leading particle candidates, and the latest experiments testing the Lambda-CDM model.