Microscope Depth of Field vs Depth of Focus
Understand depth of field, depth of focus, and resolution in optical microscopy: definitions, trade-offs, NA, wavelength, sampling, and practical tips.
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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.
Read the full article here
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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Understand depth of field, depth of focus, and resolution in optical microscopy: definitions, trade-offs, NA, wavelength, sampling, and practical tips.

You’re all set to go stargazing. You have your backpack filled with your telescope, smartphone adapter, and other items. But wait – is it the right night for you to be able to see celestial objects properly? What, exactly, is the right night for stargazing? There are some conditions you can control (equipment, location, etc.)
Learn what a Dobsonian telescope is, how to choose aperture, optics, mounts, accessories, collimation, and observing tips in this complete beginner’s guide.