Sunrise

My thoughts on sunrise today.

By and large I am not a morning person.  Oh, I’m up most days – but I don’t want to be up, that’s for damn sure.  And sure as hell not without a vat of black coffee, preferably Blue Mountain from Jamaica (look it up, it’s seriously that good).

Days with a shoot involved, well – that’s a different issue.

I generally try to get up with enough time to get where I’m going a good 30 min ahead of when the sun even thinks of peeking over the horizon.  That way I can scout around and find good shots, and put thoughts into something other than “oh crap I’m missing the best light!!”

Speaking of which, there are multiple types of sunrise on any given day.  For example:

  • Sunrise: when sun actually is above the horizon on a flat horizon.
  • Civil twilight: starts when the sun’s center is 6 degrees below flat horizon (generally 30 min before sunrise) and ends at sunrise. (exact time depends on latitude and season).
  • Nautical twilight: starts when the sun’s center is 12 degrees below horizon. Generally starts 30 min before civil twilight
  • Astronomical twilight: starts when the sun’s center is 18 degrees below the horizon. Generally another 30 minutes again.
  • And my favorite (not actually a technical term): actual sunrise, i.e. when the sun finally peeks up over whatever’s in the way of the horizon, typically mountains.

And in order to determine the actual sunrise, you’ll need the following:

  • The time of civil sunrise (there are plenty of great apps for this or you can go online and use NOAA’s solar calculator.
  • A rough idea of how much higher those mountains are than your shooting elevation, and how far away. Use a topo map for this.
  • Some wicked high school trig skills. The angle of those mountains relative to your location is

tan-1(height/distance)

  • And no I did not need a textbook to figure that out. I have freakin’ math degrees, thank you very much.  And yes that’s plural!
  • Knowing that angle and that the sun rises about 15 degrees/hr, you can calculate when the sun will peek over that mountain range!
  • Or for you non-mathy folks (like my fiancee, who pointed out that her head would explode if required to use an inverse tangent function): hold your hand out against the horizon so that your four fingers “count up” from the horizon. Each finger is roughly 15 minutes of sunrise time.  Count based on that.

So now you’ve got when to arrive, and when shooting will commence.  Last thing is to keep a set of graduated neutral density filters on hand in case the exposure of lit vs. unlit areas is too far apart.  Or use your camera’s HDR function, or post-process HDR using bracketed shots.

Oh and a tripod is assumed for this sort of thing.  Just in case you wondered.  Or the hands of a surgeon if you’re fortunate enough to have them.

Put all that together and you can come up with some killer stuff.  Like the following, from Mono Lake a few weeks ago.

Sunrise at Mono Lake
Sunrise at Mono Lake
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