Dorking around with a DSLR

I read the chapter in Nightwatch about beginner astrophotography and decided to try some wide angle shots with my old Canon Rebel XT (350D), a Canon 28mm f/1.8 lens, and a decent tripod setup with shutter remote. It was a lot of fun, particularly once I realized it’d be more interesting if I pointed the camera *at* something instead of just taking pictures of random parts of sky.

My first real success was a photo of Lyra. Vega was the brightest star visible in the sky, and while Lyra is kind of a crummy constellation it was easy to find. One neat thing I learned; Epsilon Lyra is a double star. I was able to see that quite clearly in the 10×50 binoculars, but couldn’t get a clear double image in a photograph. I also took pictures of Draco nearby, Cassiopeia overhead, and Cygnus to the left. I was hoping to get some interest image of deep sky objects like a cluster but without magnification of course that’s not happening.

My best images were at ISO 800, f/2.8, 15-30 seconds. ISO 1600 is really noisy on the 350D and ISO 400 isn’t fast enough. I didn’t try different apertures  f/2.8 is as far as I want to push this f/1.8 lens. The exposure meter in the camera seems to actually work but most of the images came out overexposed, too much purple for a dark night sky. Also the overexposure tends to flatten the resulting star brightness, it becomes hard to pick out constellations because the 1.0 magnitude stars look the same as the 4.0 magnitude stars in the image.

It doesn’t help that I couldn’t really focus right. I don’t know what I should expect the camera to be able to do, but all I could manage was winging it with manual focus to infinity. Only what is infinity? These lens let you focus a bit past infinity. And focussing in the viewfinder was impossible. So mostly I just guessed on the focus ring and then looked at the images.

The viewfinder is way too damn dark to see anything through. I ended up sighting images through the flash hotshoe, I wonder if someone makes a tiny spotter scope that will fit into it?

The fun thing about the dSLR is the long exposure gives you super vision. I could look at a patch of sky and see, oh, 10 stars. Then take an image and presto! Hundreds of stars visible in the picture. I can see why people get excited about this. Being able to image a nebula or cluster must be a lot of fun. But I’m a long way from having the telescope and mount I’d need to do that.

Some photos below. Unretouched, just the Lightroom development of the raw files. I have no idea how to edit images like this.

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