The Eclipse is just 11 days away. Time to get your gear out & ready.
You can shoot the eclipse with anything ... however there are some rules and
some tips. Take them for what they're worth, but so far, I have photographed 4
solar eclipses - 3 total - including "the Big One" in Baja, Mexico - and 1
annular. eclipse.
This time, we're taking our chances (you can always get clouded out) in Casper,
Wyoming.
Rules of the road...
1) Other than during totality (assuming you're going to be in the path of
totality) you MUST have a solar filter on your lens at all times. An 8x ND
allows 1/256th of the light through. A solar filter allows 1/100,000th of the
light to pass. Other than to look at the sun, you cannot see through a solar
filter. If you can see through the filter you plan to use, it's not good
enough.
Without that, three things can happen. IF you're using a DSLR, the heat from
the collected sunlight (assuming a long lens) can overheat and crack the
pentaprism in your camera. You'll then need a new one. Serious. I've seen it
happen. Secondly, if you're crazy enough to look through the viewfinder, the
lens collects far more light than your eye. Temporary or even permanent
blindness is a likely outcome. (Not to mention the painful burning sensation.
I've seen that happen, too!) And lastly, if you're using a mirrorless camera,
the sustained image of the sun on the sensor will likely destroy the sensor.
In the old days, you could use several layers of exposed b&w film. That does
not work, these days, as modern films have almost no silver content... and it
was the silver that did the trick. If you've not purchased solar viewers or
solar eyeglasses (reminiscent of the old, red/green 3D glasses with cardboard
frames) you can always use some welder's glass. It gives a horid, green image,
but you can safely view the eclipse. If you use welders glass, you *may* be
able to play with the colours, in post, to get a yellow/orange sun.
2) To get a decent size image of the sun, you'll need some long glass. (800 to
1200 is considered ideal, to cover the sun, but also have room on a 35mm frame
for the corona, which is only visible during totality, but can be far larger
than the sun, itself.)
But the longer the lens, the shorter your exposure must be, just because of the
rotation of the earth! (Really!) The table below shows the size of the imaga
of the sun that you'll get for any given focal length and the longest exposure
you can use before rotation of the earth causes problems. (The table is set up,
using tabs. If it comes out garbled on your screen or printer, send me a
private email (dsy@xxxxxxxxxxxxx) and I'll send you a formatted PDF file, that
you can print out, for reference. Either that, or do the calculations yourself.
The formulas are at the bottom of the chart.
Image
Exposure
FL (mm) = (size in mm) (seconds)
=
8 mm = 0.07
42.5
9 mm = 0.08
37.8
12 mm = 0.11 28.3
16 mm = 0.15 21.3
18 mm = 0.17 18.9
21 mm = 0.19 16.2
24 mm = 0.22 14.2
28 mm = 0.26 12.1
35 mm = 0.32 9.7
50 mm = 0.46 6.8
75 mm = 0.69 4.5
90 mm = 0.83 3.8
105 mm = 0.96 3.2
135 mm = 1.24 2.5
180 mm = 1.65 1.9
200 mm = 1.83 1.7
300 mm = 2.75 1 sec.
400 mm = 3.67 1/2
500 mm = 4.59 1/8
600 mm = 5.50 1/8
800 mm = 7.34 1/15
1000mm = 9.17 1/30
2000mm = 18.35 1/30
Image Size = Focal Length /109.
Exposure = 340/Focal Length.
3) Use the heaviest tripod you have. If it's a lightweight one, add a bag or
two of sand nor rocks, somehow, to give it more mass.
4) Use a cable/electric release. If you don't have one, use the self timer.
Compose your shot so that you have time, if it's 12 seconds, as the sun will
likely move, within the frame. (How much will depend on your FL.) I usually
find the 2 second delay works well - especially if you've got a mirroless, that
has an electronic shutter.
5) Bracket heavily! Use your meter, for a start, but cover several stops, as
thinks can go west, fast. A spot meter, f'rinstance, will do well during the
partial phases but will not work at all reliably during totality - assuming it
gives you a reading at all.
6) The total eclipse lasts 2 hours from first through fourth contact. Follow
Dr. Ted's advice. Be the first to arrive and the last to leave. You never
know when a passing cloud might make for a spectacular shot!
7) Don't worry if you have a reflex (mirror) lens. They suffer from low
contrast, but believe me - a solar eclipse is the highest contrast subject
you'll ever see. It will be fine!
8) Above all, don't forget to look up and enjoy a view that most of us will not
see again, in our lifetimes.
There are likely other tips and stories, but I've now been up for over 18 hours
and I'm pooped. I'll likely add more in the next day or three.
G'night!
David.
--
David Young - Photographer
Logan Lake,BC, CANADA
Website: www.furnfeather.ca
Gallery: The Creative Co. Merritt, BC.
E-book: http://tinyurl.com/ABHoP
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