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ArcticMyst Security by Avery

Incredible Photo.






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What a stunning capture, WOW!!!

Hey Pi R Squared, I did a google search for that, here you go .....
Vesuvius has erupted frequently and is the only volcano on the European mainland to have erupted within the last hundred years. Today, Vesuvius is regarded as one of the most dangerous volcanoes in the world because of the population of 3,000,000 people living nearby and its tendency towards explosive (Plinian) eruptions. It is the most densely populated volcanic region in the world.

Thanks for that, that is the one I was thinking of. It is famous for the eruption in the year 79 that destroyed the Roman cities of Pompeii and Herculaneum. There are 18 towns within the 12 kilometer (9 miles) red zone including the city of Naples, a city of about 1 million only 9 kilometers distance!:eek: Shame on the government of Italy, the EU, and the UN, the Italian government with international assistance should be spending billions of Euros to relocate those people and close down everything within a 15 kilometer radius! The worst natural disaster that has happened in my lifetime was that south east Asia earthquake and tsunami that killed about 280,000 people in 2004. If Vesuvius erupts, it will be many times worse.

Glad you guys like it too.
I keep having to go back and have another look at it as well.
It looks so surreal, quite an amazing shot.
Looks like it was an extended exposure of at least a few seconds.

:beer:

It is unlikely that it was an extended exposure of a few seconds, the ash plume and pyroclastic flow travel at very high speed, however awhile after the eruption the ash plume can appear to stand still for a time. Here is a couple of videos:



Alan
 
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It is unlikely that it was an extended exposure of a few seconds, the ash plume and pyroclastic flow travel at very high speed, however awhile after the eruption the ash plume can appear to stand still for a time. Here is a couple of videos:

Alan

The reasons I think it's a least a few seconds of exposure are these:


  • For a night landscape (nightscape) photo like this, it's virtually impossible to take a quick exposure (say less than 1 second) and have the photo exposed so well, even at high ISO and an open aperture of say f/1.2.
  • To get it properly exposed at a short exposure from this distance, you'd need a tremendously huge Flash Gun, much bigger than any available today.
  • So this leaves us with how did he get the required light to expose the plume and side of the volcano? It was the lightning strike that provided the light and this was equivalent to the huge Flashgun needed. But a lightning strike is very quick say a 'fifth' of a second so he would have been wasting his time 'trying to expose the volcano at a 'fifth' of a second while not knowing when the lightning would strike. Therefore what he did was use a high ISO and expose for a few seconds and hope to capture the strike and at the same time allowing the camera enough time to capture the rest of the scene exposing it nicely.
  • He would have used a wide angle lens to get the whole scene in and with wide angle lenses you wouldn't see enough detail to see the movement of lava flow and plum in a few seconds exposure, there's not enough detail to show this from that distance.
  • Lastly have a look at the stars, they are not perfectly round like you'd get in a very short exposure, they are trailing which is because the earth rotates. He's tried to minimise the obvious trailing by keeping the exposure just low enough to a few seconds so the star trailing isn't obvious but long enough to expose for a few seconds for the reasons above, this is the tell tail sign of a longish night exposure (see close-up below).
Volcano-by-night-closeup.jpg


RB

:yh:
 
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Pman

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Awesome! It looks kind of surreal like it's fake (I'm NOT saying it is).
I think he meant "wallpaper" as in background for computer screen and not wallpaper for actual walls;)
 
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GSS

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RB, pictures or not your posts are great:beer: I love when an expert shares his knowledge:)
 




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