i wonder what the correct color of the sky is? if you look at this links you can see that almost every image has a different blue color for sky.

http://www.flickr.com/search/?q=equirectangular

i am wondering now if someone knows what the default color of the sky is during the middle of the day, in the morning  and at night. not with clouds. only the sky.

i know that this is on google. but i can not find it. so it would be great if someone can help me.

thanks