03 September 2017

Moonless night

According to the astro-photographers, moonless nights are the best to make this particular type of photography. The reason for that is obvious: most of the time the moonlight is so intense that, for the exposure needed to correctly record the celestial bodies, all the foregrounds will be prohibitively over-exposed. Most of the times pictures are taken above ISO 3200, with shutter speeds around 20 to 30 seconds (more than that and you risk star trails on the final image) and apertures between f/1.4 and f/4.0.
This particular case, althought not even close to be considered a good photograph, gives you a general idea: I wanted to shot the Milky Way against a mountain humanized foreground. So I choose the Achada do Teixeira abandoned hut/restaurant, at 1600 mts above sea level, as my foreground. Placed the camera on tripod and choose my point of view for composition. ISO 6400, f/4.0 and 30 secs exposure gave me the best result possible for the Milky Way. Problem was that the hut would become a dark, textureless, shadow using those parameters. Increasing the exposure to lit the hut would only burn out the sky, due to the residual amber light reflected to the atmosphere from the villages down under, at sea level.
So I opted instead to "paint" with light, for about twenty seconds while the shutter was open, just a little bit of the foreground, from the position where I stood with the camera and with a simple pen-sized-chinese-made LED torch, powered by two small AAA alcaline batteries.
That a modern digital camera sensor can suck so much light from such a weak light source is to me beyond believe. I can easily imagine that twenty five years ago to have the same lighting effect on the set of a movie production with a motion film camera you'd need at least twenty thousand Watts of light to achieve the same result. Now all you need is a highly sensitive digital sensor and a pocket flash light.
So, although I'd say this modest example is light-years away to be considered photographic art, I think you (no pun intended) get the picture.
Picture taken with Nikon D610 and Vivitar manual 24mm f/2.8 lens. Sirui Travel T005 light tripod and kit ball-head. Post-processing in Adobe Photoshop CS6.

No comments:

Post a Comment