Just what the heck are civil, official, nautical and astro..

[dp1don]

I'm sure some of you may be wondering what these tems in the sunrise and sunset calculations really mean...so, here's a set of definitions, culled from various sources on the Internet.

(Google, gotta love it!)

OK:

Official: This is (duh) the moment the leading (or trailing) limb of the (refracted) Sun crosses the horizon at 0° elevation. Because of refraction, this occurs about 2 minutes different from the time expected by the Sun's relative position in space.

Civil:  Short for CIVIL TWILIGHT, the period of twilight beginning (or ending) when the center of the (refracted) Sun is more than 6° below the horizon.

Nautical: Short for NAUTICAL TWILIGHT, the period of twilight beginning (or ending) when the center of the (refracted) Sun is more than 12° below the horizon.

Astronomical: Short (well, medium length actually) for ASTRONOMICAL TWILIGHT 9no surprise there, really), the period of twilight beginning (or ending) when the center of the (refracted) Sun is more than 18° below of horizon.

There's a recurring theme here....each one is longer than the previous...and has to do with how useful the light is (or in the case of astreonomical, how soon it interferes with observations).

So, how can you use these?

Well, in my skins (AximSlideX3 and AximSlideX5), I use the following code:

Code Select Expand

image,2,12,sunrise.png,
suntime,%var0%,sunrise,official,24,12,HH:mm,,,l

image,2,26,sunset.png,
suntime,%var0%,sunset,official,24,26,HH:mm,,,l

Just change Official to Civil, Nautical or Astronimical and watch your day's change length.

Of course, you could also add in a little flag to let you know what set of time's you're using:

Code Select Expand


text,24,0,[name]{sunrise type id},c


FOr example:

Code Select Expand


changefont,Frutiger Linotype,11,b
text,2,0,[name],l
changefont,Frutiger Linotype,6,b
text,15,23,O,r
changefont,Frutiger Linotype,11,

image,2,12,sunrise.png,
suntime,%var0%,sunrise,official,24,12,HH:mm,,,l

image,2,29,sunset.png,
suntime,%var0%,sunset,official,24,26,HH:mm,,,l

This puts the little letter designator directly between the sunrise and sunset icons.

Anyway, hope that helps...

[fishboy]

Nice work on the information.  I had added this information to the Skin Reference commands for version 0.11.0, but never released it because of the need for more info, and because of the eminent release of 0.12.0.  The info I have is very similar, and we probably got it from the same place.  But mine does not have any witty remarks, just dry and boring technical stuff.  

[blatty]

I removed CIVIL from that part of my skin and left the field empty and the time came closer to what weather.com shows for sunrise and sunset.

Therefore it must be using a default...does anyone know if that is the same as the OFFICIAL setting?

[fishboy]

Athought you could have tested this yourself by changing the values yourself and looking at the results, I removed the "civil" suntime parameter (leaving it blank) and got no where near the correct time (of course I am testing with pre beta version of 0.12.0).  So my advice is to always specify a value for this parameter.