Yes, that is correct. I frequently use this calculator when trying to calculate these things: http://www.rapidnet.com/~rernster/in...calculator.htm
By the way, just a bit of hopefully constructive criticism - you may want to consider cropping out, or editing out, that rope tie down that is at the very bottom edge of the frame. Not really a big issue either way, but worth considering the image with/without it. Cool image though, very dramatic high contrast.
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