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:beer:Hello all.
I decided to make a new thread and use my knowledge of "Astronomy" to make a fun little thread that can maybe help you members with your pictures or this could be a fun little thread to read
I this Thread the following topics will be discussed:
Civil Twilight
Nautical Twilight
Astronomical Twilight
I will mostly talk about how each one affects the sky and please do take notice all these are either before/after | sunrise/sunset.
Let's Start:
Below I have included a small graph of the different twilight's so you can all be familiar.
Civil Twilight (Sun is less then <6 Degrees below horizon)
-This form of twilight occurs right after/before sunrise or sunset and is the *brightest form* of twilight
-Depending on your latitude this phase can take 1 hour(equator) to 2 hours(Far North) to pass into the following twilight
-Fun Fact: If you live above 60° 33′ 43″ N or 60° 33′ 43 S″ during the summer months it will not get darker then this :wave:
-Major Cities(darkest during summer): Nuuk, Hammerfest, Salekhard, Anchorage, Reykjavik, Tampere, Whitehorse
Nautical Twilight (Sun is less then <12 Degrees below horizon)
-This form of twilight occurs of course right after *Civil Twilight* and in large cities can be almost undistinguishable from nighttime because of (Light Pollution)
-This form of twilight can last for 1 hour(equator) to many hours just above the Artic Circle(during winter)
-If you want to see your lowered powered green lasers beam(<5mW) this is the earliest possible time :na:
-Fun Fact: Sailors now must startusing stars as navigation instruments since the horizon line is no longer visible
-Fun Fact#2: If you live above 54° 33′ 43″ N or 54° 33′ 43″ S it does not get darker then this during the summer months :evil:
-Major Cities(darkest during summer): Moscow, Edmonton, Stockholm, Glasgow, Belfast, Juneau, Ushuaia, Grande Pairie
Astronomical Twilight (Sun is less then <18 Degrees below the horizon)
-Darkest of all Twilights(most if not all stars are easily seen)
-In major cities this appears to be nighttime when it is not completely dark yet :shhh:
-Lasts less then 30 mins(equator) or 5 or more hours(near the poles)
-Fun Fact: If you live above 48° 33′ 43″ N or 48° 33′ 43″ S it does not get darker then this during the summer months
-Major Cities(darkest during summer): Paris, London, Berlin, Vancouver, Warsaw, Calgary, Winnipeg, Manchester, Brussels, Kiev, Prague, Minsk
I also have a tool below which can show you in real time the current sky conditions outside:
Sky View Cafe - Astronomy - Star Charts and Ephemeris
Ending:
Thank you all for reading. I hope this has helped you in a small way to create even better pictures then you all do and make them exceptional with the perfect sky lighting.
If you have any suggestions/comments please let me know :beer:
Sources:
Pictures: Google Images
List of some cities: Wikipedia/My head:crackup:
I decided to make a new thread and use my knowledge of "Astronomy" to make a fun little thread that can maybe help you members with your pictures or this could be a fun little thread to read
I this Thread the following topics will be discussed:
Civil Twilight
Nautical Twilight
Astronomical Twilight
I will mostly talk about how each one affects the sky and please do take notice all these are either before/after | sunrise/sunset.
Let's Start:
Below I have included a small graph of the different twilight's so you can all be familiar.
Civil Twilight (Sun is less then <6 Degrees below horizon)
-This form of twilight occurs right after/before sunrise or sunset and is the *brightest form* of twilight
-Depending on your latitude this phase can take 1 hour(equator) to 2 hours(Far North) to pass into the following twilight
-Fun Fact: If you live above 60° 33′ 43″ N or 60° 33′ 43 S″ during the summer months it will not get darker then this :wave:
-Major Cities(darkest during summer): Nuuk, Hammerfest, Salekhard, Anchorage, Reykjavik, Tampere, Whitehorse
Nautical Twilight (Sun is less then <12 Degrees below horizon)
-This form of twilight occurs of course right after *Civil Twilight* and in large cities can be almost undistinguishable from nighttime because of (Light Pollution)
-This form of twilight can last for 1 hour(equator) to many hours just above the Artic Circle(during winter)
-If you want to see your lowered powered green lasers beam(<5mW) this is the earliest possible time :na:
-Fun Fact: Sailors now must startusing stars as navigation instruments since the horizon line is no longer visible
-Fun Fact#2: If you live above 54° 33′ 43″ N or 54° 33′ 43″ S it does not get darker then this during the summer months :evil:
-Major Cities(darkest during summer): Moscow, Edmonton, Stockholm, Glasgow, Belfast, Juneau, Ushuaia, Grande Pairie
Astronomical Twilight (Sun is less then <18 Degrees below the horizon)
-Darkest of all Twilights(most if not all stars are easily seen)
-In major cities this appears to be nighttime when it is not completely dark yet :shhh:
-Lasts less then 30 mins(equator) or 5 or more hours(near the poles)
-Fun Fact: If you live above 48° 33′ 43″ N or 48° 33′ 43″ S it does not get darker then this during the summer months
-Major Cities(darkest during summer): Paris, London, Berlin, Vancouver, Warsaw, Calgary, Winnipeg, Manchester, Brussels, Kiev, Prague, Minsk
I also have a tool below which can show you in real time the current sky conditions outside:
Sky View Cafe - Astronomy - Star Charts and Ephemeris
Ending:
Thank you all for reading. I hope this has helped you in a small way to create even better pictures then you all do and make them exceptional with the perfect sky lighting.
If you have any suggestions/comments please let me know :beer:
Sources:
Pictures: Google Images
List of some cities: Wikipedia/My head:crackup: