This is a composite showing the sequence of events surrounding totality at the April 8, 2024 total eclipse of the Sun, from just before totality (at upper left) to just after totality (at lower right), with totality in the middle. Or, in eclipse terms, from just before second contact (C2) to just after third contact (C3).
Time runs from left to right here, with the last bit of the Sun's photosphere about to disappear behind the advancing dark disk of the Moon at top left, creating the diamond ring effect. As the sunlight disappears it breaks up into smaller bright bits, the Baily's Beads effect, created by sunlight shining through low craters and valleys on the edge of the Moon. What remains briefly, before the advancing edge of the Moon covers them, is a thin edge of pink light, the chromosphere, and at this eclipse, several pink prominences leaping off the surface of the Sun.
At lower right the reverse occurs, with a pink rim of the chromosphere appearing from behind the Moon first, followed by another show of beads of bright sunlight from the photosphere bursting through valleys on the lunar limb, until they merge to form the large bright final diamond ring. At the end of totality at this eclpse, a set of particularly large and detailed prominences appeared.
The prominences are pink from a combination of wavelengths, mostly from hydrogen, but also helium and magnesium emission lines.
The two time-lapse C2 and C3 sequences flank a central blend of exposures for the totally eclipsed Sun and its pearly corona, its outer atmosphere. I have chosen exposures to show just the brighter inner corona so as not to overpower the flanking images of the prominences and chromosphere.
The actual official start of totality at C2 and end of totality at C3 occur about halfway through each sequence. The glows around the diamond ring bursts of sunlight at either end are from the high cirrus clouds the Sun was embedded in at my site on eclipse afternoon. The angle of the images roughly reflects the direction the Sun was moving in the afternoon sky, but the Sun would not have moved as much as this across the sky during the roughly 4 minutes covered by these images. I spread out the images in layers in Photoshop so you can see the changes along the edge of the Moon.
The images have celestial north roughly at top. The diamond rings are not 180° opposite each other as I was north of the eclipse centreline at my site at Lac Brome in the Eastern Townships of Quebec, Canada.
I shot all the images with the well-traveled Astro-Physics Traveler 105mm refractor at 600mm focal length and f/6, with the Canon R5 at ISO 100. This was the sixth central (4 totals and 2 annulars) for the 30-year-old Traveler scope. It was tracking the Sun on the Astro-Physics AP400 mount, just recently returned from a 20-year stay in Australia.
The contact sequence images are all 1/1000 second, with 20 for each side selected from hundreds (272 at C2 and 327 at C3) taken during two rapid-fire continuous shooting modes at the start and end of totality, that shot at a rate of about 15 frames per second. I chose every 12th frame starting at the frames closest to totality and working back or forward through the sets. So the sequences show the changes at a regular interval of 0.6 seconds apart, over a duration of 12 seconds for each set. This demonstrates how events unfold very quickly before and after totality.
The central totality image is a Mean stack mode blend of 7 exposures from 1/800 to 1/50 second, plus a single short prominence image layered in with a Blend-If adjustment.
All frames were retained at their original 45-megapixel sizes from the R5 originals. Sharpening applied to each frame with ON1 NoNoise/Tack Sharp AI 2024.
