Readers of our travel blog saw that our trip to my mother’s hometown in Missouri to witness and photograph the total eclipse of the sun of August 21, 2017 was a complete success.
Photographically, the challenge for me was exposure. I’d never even seen a total eclipse before, and could only guess. The solar corona, an aura of energetic plasma that represents the most visible and photographable attraction of an eclipse, is as much as a million times dimmer than the photosphere of the sun. The internet was little help for numbers on this exposure, which surprised and annoyed me.
For this eclipse, the best exposure was f/8, 1/80th of a second at ISO 640.
I used my Nikkor 400mm f/3.5 coupled with its well-matched TC-14 1.4x teleconverter to make a 560mm f/4.5, which I stopped down to f/8 for maximum sharpness and to tame this lens’s slight inclination toward chromatic aberrations. This lens is from the era before autofocus, but was build at a time when quality construction and expensive materials made a photographic instrument of unchallenged capability. In its day, sports photographers often thought and dreamed of little else than this “sweet piece of glass.”
I got my 400mm in 1997 from the long-defunct Photo-Fax.com, a service that catered to us, we who wanted to pay discount prices for top-dollar gear. It’s the longest lens I own.
With the teleconverter, the 560mm focal length was beginning to be long enough to fill the frame with the moon blocking the sun, showing the solar corona…
If you were building an eclipse camera on a budget from scratch, I might consider one of the new Sigma or Tamron 150-600mm lenses. Both companies make 1.4x teleconverters, which makes the 600mm into 840mm, but also robs the lens of a full f/stop of light. (Do the math: f/number = focal length ÷ aperture diameter.) Shooting at f/8.8 results in shutter speeds duing totality of 1/10 at medium ISOs. It’s also worth considering that most telephoto lenses aren’t incredibly sharp at full aperture, and the situation gets complicated.
It probably goes without saying that a sturdy tripod is a must.
Alternatively, you could opt for renting a super telephoto. You can get a Nikkor 800mm f/5.6 AF-S for a weekend for $400 or so.
Don’t bother with the super-cheap 500mm catadioptric (mirror) lenses. They really are junk.
Finally, there are many fine astronomical telescopes with camera adaptors that will do the trick, but their prices are also astronomical.
In less than seven years, another total eclipse will cross the United States, and the path of totality will be even closer to home than this one. On April 8, 2024, Abby and I hope to be in the vicinity of Idabel, Oklahoma, just 148 miles from our home. With the experience I gained from this time, I will plan to expand my goals to include more cameras, more lenses, and more photographic schemes, and hopefully take the next eclipse to the next level.