This is not another post about the eclipse. Well, maybe. A little.

Text and Photos by Mason Resnick

Let's talk about the Eclipse. And the sunny 16 rule in photography. And the comfort of consistency. 

Here’s a basic concept in photography: It’s easy to get a perfect exposure on a sunny day without using your camera’s autoexposure or light meter. (Warning: Math ahead for the next 3 paragraphs!) Take your ISO (light sensitivity setting), use that number as the denominator for your shutter speed (exposure length). In other words, if you’re shooting at ISO 100, choose 1/100 second. Then, set your aperture (which controls the amount of light the lens lets in) at f/16. In other words, a perfect exposure on a sunny day is ISO 100, 1/100 second at f/16.

If you’re shooting at ISO 400, your exposure is 1/400 at f/16. You can then halve or double exposure and double or halve the size of your aperture; for example, f/800 at f/11, or /200 at f/22. And so on.

What if it’s a partly or fully cloudy day? What about later/earlier in the day when the sun is lower? How about in the shade? All calculations are based on subtracting light from the Sunny 16 rule; Light overcast? Try f/11. Thunderstorm clouds? Shooting in open shade? Switch to f/8. And so on.

If you’re not familiar with these calculations, you might want to take my upcoming class, Fearless Photography, which will take place over 4 Tuesday evenings in May in my studio in Highland Park, NJ. (Why yes, my dear, that WAS a shameless plug. email me for details at masonresnick@gmail.com.)

That’s known as the Sunny 16 rule and it is consistently correct whenever there’s a sunny day. Day in, day out, we can rely on the same level of luminosity to emanate from the star that provides light, warmth and life to the planet we call home.

This was not the case in a swath of of North America over several hours on Monday, April 8, 2024. That’s when we experienced a partial or (if you were lucky enough to be in the right place at the right time) total solar eclipse. 

Although I wasn’t in the path of totality, the moon did block around 90 percent of the Sun. It was somewhat cloudy and the view of the sun was obscured at times. The skies got dusky and it started feeling a little darker and a little cooler; it was substantially darker than it seemed. That’s because our eyes automatically dialate in response to lower light. So it seemed lighter than it actually was. My light meter doesn’t lie, though, and it showed the light reading to be around 4-5 stops lower, or around 75-80% darker (1/100 second at f/4 at ISO 100) at the darkest point of the eclipse.

I found the measurable difference in ambient light to be both fascinating and momentarily disconcerting. 

Photo by Mason Resnick

As a photographer, I’m hyper-aware of light and changes to light. After all, photography = photo grafis = painting with light. And on that day, for that hour or so, the light I was familiar with had changed dramatically. The natural order of things seemed to be thrown asunder. 

Of course, eclipses are part of the natural order of things, and can be predicted down to the second because math and science—neither of which I excelled at—say so. But the event's rarity causes a bit of havoc with humans’ perceptions and emotions, and on some deep level, challenges our sense of familiarity. 

For some who don’t trust or rely on the science of eclipses, the event can be interpreted on apocalyptic terms. It’s fodder for some entertaining memes. Nevertheless, even the most rational among us can stand in awe of the phenomenon when we have the opportunity to experience it.

When the moon blocks the Sun’s light for a few minutes, life undergoes significant changes. Just as photographers need to adjust camera settings to compensate for this awesome natural phenomenon, humans need to adjust our mindset so we can experience this temporary change in the status quo without anxiety. 

We can take a moment to appreciate the Sun’s steady glow, day in and day out. Those of use who pray can say a blessing of gratitude over something we take for granted almost all of our lives. Maybe we can learn from eclipses to be grateful for this aspect of our day-to-day existence.

And then, hopefully inspired, we re-set.