Numerical Aperture, Resolution & Microscopy Illumination
Understand numerical aperture (NA), resolution limits, depth of field, and Köhler illumination. Learn how NA, condenser settings, and sampling affect image quality.

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.
Understand numerical aperture (NA), resolution limits, depth of field, and Köhler illumination. Learn how NA, condenser settings, and sampling affect image quality.
Explore Orion’s stars and nebulae. Learn how to find Orion, observe M42 and the Horsehead, track the Orionids, and understand Betelgeuse’s 2019–2020 dimming.

In this day and age, it seems like there are a million gadgets out there to perform all kinds of niche purposes. The Brix refractometer might sound like one of them, but the truth is that this instrument is immensely useful in a variety of circumstances. If you’ve been searching for a refractometer that can