2017 Great American Eclipse August 21, 2017

  • Astrophotographer and Editor: Fritz Stafford
  • Published: August 22, 2017
2017 Great American Eclipse – Pre-Totality

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2017 Great American Eclipse – Totality

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2017 Great American Eclipse – Post-Totality

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Equipment / Settings / Conditions: Vernon Scope 80mm f6 Brandon apochromatic refractor; Canon 60Da camera (APS-C image sensor format => 1.6 effective focal length multiplier) at 100 ASA; white light solar filter for solar disk images with exposures 0.004 – 0.005 seconds); unfiltered solar corona images at ~0.04 – 0.15 seconds; weather was clear but with moderate smoke haze.

Note that sun spots are visible on most of the solar disk images, especially when viewed in full screen mode on displays ~17 inches and larger.

Also note the solar corona is not homogeneous and increasingly diffuse with distance from the sun but rather ray-like with bending rays of varying lengths.

At our location, 44 degrees 11 minutes North Latitude 115 degrees 59 minutes West Longitude and 3850 feet altitude, the temperature at 11:00 AM was 78F, and then it dropped to 68F by 11:30 AM just after conclusion of totality.

The light just prior and immediately after totality was surreal. It was nothing like low light at dawn or dust where sun light is scattered by overhead dust in the atmosphere. This was direct sun light, undiffused by clouds, but at very low <1% flux of normal direct sun light. I cannot explain why this light was so special, but I know I cannot replicate it with low light of any type in a darkened room.

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