Glendo State Park, Wyoming

Exposure Data

Various exposures
ISO200 @ f8


Nikon D7100
Nikon 300mm f4
Nikon 2x Teleconverter
Orion Deluxe Safety Solar Filter
iOptron Cube Pro


Eclipse Orchestrator
Photoshop CS6

Solar Eclipse - August 21, 2017

First Contact 20% 40% 60%
80% Diamond Ring Baily’s Beads Maximum Eclipse
Baily’s Beads Diamond Ring 80% 60%
40% 20% Fourth Contact

The above grid shows the sequence of events for this eclipse. The event timings for this eclipse were: First Contact - 10:24 AM, Second Contact - 11:45 AM, Maximum Eclipse - 11:46 AM, Third Contact - 11:47 AM, and Fourth Contact - 1:12 PM (MDT). Totality lasted for 2 minutes 29 seconds.


First Contact - During a solar eclipse, the moment the Moon makes contact with the sun; this marks the beginning of the eclipse.

Second Contact - During a solar eclipse, the moment the Moon covers 100 percent of the sun's disk; the instant totality begins.

Totality - During a solar eclipse, the length of time between second and third contact; any instant the Moon covers 100 percent of the Sun's disk.

Third Contact - During a solar eclipse, the instant totality ends.

Fourth Contact - During a solar eclipse, the moment that the disk of the Moon breaks contact with the sun; this moment the end of the eclipse.

Baily’s Beads - The effect often seen just before and just after totality when only a few points of sunlight are visible at the edge of the Moon, caused by the irregularity of the lunar surface; named after English astronomer Francis Baily, who first explained it in 1836.

Corona - The shell of thin gas that extends out some distance from the Sun's surface, normally visible only during totality; corona is the Latin word for "crown."

Diamond Ring - The effect just prior to or just after totality of a solar eclipse when a small portion of the Sun's disk plus its corona produce an effect similar to the real-world object it's named after.

(Definitions Source - Astronomy Magazine)


Solar Eclipse - 08/21/2017, Sunspots. Copyright 2017 Richard McCoy

Two groups of sunspots were seen on the solar surface on the day of the eclipse; AR2671 and AR2672.

Sunspot - A temporarily cooler (and therefore darker) region on the Sun's visible disk caused by variations in its magnetic field.

(Definition Source - Astronomy Magazine)

Diamond Ring

Solar Eclipse - 08/21/2017, Diamond Ring. Copyright 2017 Richard McCoy

Baily’s Beads

Solar Eclipse - 08/21/2017, Baily’s Beads. Copyright 2017 Richard McCoy


Solar Eclipse - 08/21/2017, Prominences. Copyright 2017 Richard McCoy

A number of prominences were seen on the solar limb during the eclipse. Two are shown here.

Prominence - A large scale, gaseous formation above the surface of the Sun, usually occurring over regions of solar activity such as sunspot groups; during totality, observers often see prominences seeming to erupt from the dark edge of the Moon.

(Definition Source - Astronomy Magazine)

Maximum Eclipse

Solar Eclipse - 08/21/2017, 11:46 AM. Copyright 2017 Richard McCoy

The image above is a composite of exposures centered around 11:46 AM; maximum eclipse.