Sunday, November 6, 2011

D7000 does poor man’s astrophotography …

The moon shots and Jupiter shots through the binoculars with the F550 the other day gave me a real grab tonight as the sky was crystal clear around 1am. So clear that I could see many more stars that normal, despite the continued presence of an annoying street light in my front yard. When I sit at the back of my house, the house blocks that light, so I get a nice view of the southern sky. Especially in late autumn, as the tree in my neighbour’s back yard is finally stripped of leaves :-)

The first thing I did was look at the Orion Nebula with the binoculars, and darned if I couldn’t see some nebulosity. Hot damn! I then tried to capture it through the binoculars with the Fuji X100, but I could not get the cameras aligned well enough (both on tripods for the longish exposure needed.) And then its battery died. Oh well …

I tried the F550EXR and could not see anything on the LCD. No success there.

Then I went in and grabbed the D7000 and put a Sigma 105mm 2.8 Macro lens on it (although it turned out that you focus at infinity when going through the binoculars, duh.)

I found that the LCD also refused to show me the subject so I got on my knees (the subjects were high in the sky so the camera and binoculars were tilted quite dramatically upwards) and focused manually. With the Sigma, the best focus turned out to be at the infinity end of the range at the stop.

I just could not get anything in the binoculars, so I figured it would just be easier to shoot without them in the way. Then I started to see results. For example, the first shot I made of the nebula showed it quite clearly. Here it is, as it is much better than the second one.

D7000 f/2.8 1600ISO 6s

Wow … the nebula is right there in your face. This is a crop of course, but it is surprisingly large on the sensor. This mainly due to the excellent resolution of this lens and the D7000’s 16mp sensor. It is only about 158mm effective … 3x magnification at the most.

So then I thought … what about my favorite star cluster, the Pleiades? That one turned out quite interesting …

D7000 4000ISO f/2.8 4s

I spent quite some time processing this as I was trying to strike a balance between the contrast and the preservation of what looks like a bit of nebulosity between the stars. I use a gorgeous shot of the cluster as my desktop background and these stars really are this blue and there really are blue clouds around them. This is a decent representation of the cluster and that amazes me.

I tried several shots of Jupiter then, and ended up stopping down for better resolution. I finally came up with this spectacular image, and do remember that this is shot at 158mm effective. This is exactly what was on the sensor, desaturated to remove slight blue fringing around the planet.

D7000 4000ISO f/4 1/4s

WOW! I love how excellent lenses create that lovely star effect. But look at the clarity with which all four Galilean moons are rendered. And this at 158mm!

I tried one final shot, lining up the D7000 with the Oberwerk binoculars again and shooting Jupiter. I got an image this time and it shows the spectacular amount of extra magnification available form the binoculars (10x) … but there is massive fringing and the image is simply less satisfying. But that’s ok … afocal on binoculars is really pushing it anyway :-)

D7000 4000ISO f/4 1/4s

So go out there and have some fun. You can get fascinating imagery even with short lenses if they are good enough. A macro lens like the Sigma is designed for tack sharpness at macro distances, but I was pleasantly surprised at its prowess when set at infinity. Go Sigma …