Happy Birthday : 4 Year blogging

Celebrating 4 year of blogging ... started on December 23, 2012

Solargraph Failed due to overexposure.

As mentioned earlier, one pinhole camera disappeared a month ago and yesterday I found out that after 6 months exposure my other one did not show much details.
Bad luck but what can we learn from this?
My conclusion of the latter is that the paper was overexposed. This probably because the can (this time a used a piece of a "sewer pipe") wasn't light prove, so the sun could penetrate through the can and did expose the paper.  Instead of exposing the paper via the pinhole.

Why a Red Sky in the Morning?

This morning again a beautiful red sky. But why a red sky? This because of a phenomenon called Rayleigh Scattering. When light travels through a medium with particles smaller (eg. moisture) than the wavelength of light then light will be scattered. The intensity of the scattered light is also dependant of the wavelength (～𝛌-4). For that with blue light having a 2x shorter wavelenght then red light, this means blue light is 16x more scattered then red light. That's the reason why we have a blue sky and not a red... blue is more scattered with having more chance that blue light will hit our eyes.
So now, why a red morning. Ah... this is because in the morning/evening, when the sun is low at the sky, light travels much longer then during the day through the atmosphere. The distacnce can be as even 12x longer then during daytime. So the chance that blue light is fully scattered is very likely and only the red light is available to reach our eyes (so no blue light is left :) )

Start Winter @ 11h44

Winter will start officially today @11h44. At that moment the sun will be directly overhead at the Tropic of Capricorn also known as the Southern Tropic.

Collage of moonphases december 2016

This month I was able to make a collage of the different moonphases. I started beginning of december and ended with the full moon on december 14th. Not every day was cloudfree but.. unfortunately.
This work took me about 779 minutes of which 504 minutes spread over 10days to make 133 pictures (a total of 1.16 Gb), and afterwards about 275 minutes making the final editing and establishing a collage using CS4.

Full Supermoon but not 100% full !

It's full moon today and this morning there are no clouds. So perfect time to make some pictures. It's also the third time this year (Oct, Nov) we can observe a supermoon. Also special today is that the moon is not exactly 100% full. This because the moon is not exactly in front of the sun. You can see this at the picture as some craters are still visible.

One day before full moon

With 98% illumination, the moon is almost 24h away from being "full". Below picture was taken with ISO100 and 1/160s shutterspeed.