A "once-in-a-lifetime" shot of Mount Colima during a powerful eruption | Hacker News Reader

A "once-in-a-lifetime" shot of Mount Colima during a powerful eruption

nationalgeographic.com

27 pointsdsr125 comments

interesting note: these photos are legit, except the starry background has been added afterwards to make a composite shot.

you can see that they are all identical star fields, and you can see the slight egg shaped stars at an angle, which happens when a shutter is opened for ~30 seconds or so (because stars move across the sky.) the photographer would have to have a relatively quick shutter to capture the fine details of the ash cloud burst, but at that speed it would not pick up the stars at all.

The article says the images are 8 second exposures, no mention about composites. Are you sure?

They don't appear identical to me either. If you flick through from first to last (chronologically, eg from image 2 onwards), watch the star in the very bottom-left (they all behave, but this proximity to the edge makes it more perceptible). It does exactly what it should do.

What does seem interesting (to me), is that if you do the same and watch the opposite (right) edge, you'll the stars on the left edge are travelling right (and upwards), and the stars on the right are travelling left (and upwards).

I find this novel because I've never seen this myself - I'm in Northern Europe, so what I see is stars spinning around the pole. The effect we see here is the camera pointing towards the equator, putting it facing east(ish).

Regardless, this is one area where I'm happy to defer to natgeo's ability to spot shenanigans.

okay - you are correct. photographing terrestrial objects and stars are very difficult to do in the same shot on account of light pollution.

my bad - and here, i made this as a mea culpa to show that it's legit: https://i.imgur.com/aTvpilo.gif

The fine details of the ash cloud are captured by the flash of the lightening.

Look at the other photos in the series.

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