Mark Shogren wrote:... was wondering if using nd filters would be enough ...
Short answer is an emphatic "No!"
Direct sunlight is extremely bright, and also produces an enormous amount infrared (IR). Way, way more than can be adequately blocked by normal IR cut filters such as built-into a UMP46 cam. Intense sunlight and the heat generated by the IR can almost instantaneously damaged a digital sensor.
To prevent damage to a camera sensor
mount a certified solar filter in front of the lens.
To prevent damage to your eyes
wear certified solar eyeglasses. If viewing through an optical device such as binoculars, scope, telescope, DSLR viewfinder, etc.,
mount a certified solar filter in front of the lens.
The only exception is during full totality when the sun is 100% obscured by the moon. During 100% totality a solar filter is not required. At all other times (even @ 99%!) a solar filter must be used.
Enjoy the eclipse, and be safe.
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