What do you think, are there other instances of intelligent life in the universe? I remember being fascinated about this question when I was a lot younger. Reading clever books about science introduced me to all kinds of ideas where the Drake Equation was a one solid piece of thinking to which I built my own answers. The Drake Equation describes a numeric value to the likelihood that other instances of intelligent life exists anywhere other than Earth. One way to think about the equation is to think that there are certain barriers that life in general must overcome so that it can exist out there somewhere. For example, there has to be solar systems where stars are orbited by planets that are at certain distance of the star (not too close, not too far), so they could potentially sustain life with a fitting temperature. And again, there needs to happen a birth of life which require some ingredients and probably not all planets have them in the right proportions. Then there needs to born civilizations that are more than just plants or animals. And so on, you probably know this story already.
For a long time I thought that the universe looks like it is infinite, or at least close to it, so there has to be other instances of intelligent life in the universe. But the more I thought (and read) about the barriers the more skeptic I became. It seems that one can invent a lot of additional barriers that the Drake Equation doesn't actually take into account. For example, even if there are enough solar systems with planets at suitable distance from a star, the planets need to have fitting rotation angle that is not too chaotic for climate stability (for example Earth's rotation is partly guided by the moon). Perhaps the birth of complex life needs very unlikely events which can be really anything and much more than just a pool of warm water. And so on.
However, I feel that the strongest barrier here is that in some ways the very idea of evolution crushes the idea of intelligent life. It's very common to think that evolution created man from the ape, and because of that we became more advanced. In a similar way many seems to think that the next step in the evolution of man is to inhabit other planets and other solar systems – and based on this kind of thinking we expect other civilizations to exists; that evolution has an idea of advancement built in it. But the evolution doesn't have a purpose. Neither man nor the colonizing other planets is the goal of evolution. We would like to think that this 'intelligent life' or 'man' represents some important waypoint in a big picture, but maybe it's just the way we reflect our hopes, identities and our human existence to the vast unknown – another act of anthropomorphism in the name on science? Maybe life just exist without advancing to anywhere, not like a steps of evolution which you saw on a school book, but like a roots of a tree which just spreads all around without any determined target or goal. 'Then why do we exist, we are intelligent?', I hear you saying. That's precisely a kind of question that convoy ingredients of anthropomorphism into science. One of the best manifestation of this idea is Stanislaw Lem's great novel Solaris where the oceanic surface of the planet Solaris avoids all human attempts to understand it. No matter how much the crew of the space ship try, they only see their own reflections, fears and hopes when trying to reach the Solaris. What do you see when you look at the sky?
Greg from Dpreview forums asked me to shoot some stars, so I did. I took this picture when visiting my brother who happens to live at country side pretty far from nearest cities or towns. So there was not much light pollution, but unfortunately some clouds which I only saw afterwards when looking pictures from the monitor. I'm not much a astrophotographer, so forgive me if the example is not very representative. However, it does give some clues about the Batis 2/40 CF's performance for astrophotography.
Now, I took this shot at f/2 and ISO400 with 10 seconds exposure. I used '500 rule' for this shot and even decreased a bit for as sharp stars as possible (actually with 10 seconds it becomes a '400 rule'). As I haven't done a lot astrophotography I adjusted the ISO to my liking where it seemed to match with what I was pretty able to see with my own eyes (later on I pushed the file 1,5 stops in Lightroom). I'm sure someone would have made different choices, and maybe someone can educate me here a bit, but I thought that I wanted to create a picture where the end result would at least in some way resemble the actual scene - in other words, I intentionally didn't want to go for 'my god, it's full of stars!' -look (another 2001: A Space Odyssey reference).
So, how's the coma performance I hear you ask. I'm definitely not an expert here, but to me it looks pretty good at f/2. Sure there is little bit of butterfly wings there in the corner, but that's about it. Looks like the biggest stars are only affected and small ones are actually very good (this was the biggest butterfly I could find from the frame).
If we stop down to f/2.8 the coma performance of course gets better. Here you can see a crop from picture taken at f/2.8 and again I've tried to find the biggest butterfly from the corner. Not much left really.
Based on this limited experience I think the Batis 2/40 CF's optical performance is good for astrophotography, but being a 40mm lens it doesn't fit into that genre as nicely like, for example, Batis 2.8/18 would. With the wider angle one can work with longer exposure times which of course turns into better image quality. Also, wide angles fit better for milky way shots and alike, because one can get more of them into single frame. Nevertheless I believe the optical performance doesn't setup barriers for Batis 2/40 CF to be used in astrophotography, if that is something one is interested to do with it.
Ps. There’s a good (more detailed) Batis 2/40 CF coma test done by another Finnish photographer Riku Talvio. You can find it here.