On the few recent clear (and quite cold) nights we’ve had here I took the Canon out to do some star pictures. This camera has some advantages over the Nikon when it comes to shooting in the dark. For one thing it has a shutter time of up to 30 seconds, plus bulb if you want to go longer, which is not dependent on the ISO. It also has a higher ISO rating, but that isn’t particularly important. In short you have more exposure options available.
Another advantage is that the Canon has interchangeable lenses, which is a real blessing. In the dark looking at the sky, autofocus doesn’t work and I for one can’t see well enough to focus manually. The Canon’s kit lenses don’t have markings on them for distance either, so you can’t “set and forget”. However I have some very nice old Pentax Super Takumar lenses which do have distance markings; twist to infinity and you’re done. Since there’s nothing in the foreground in these images depth of field is not a concern, so you can use the lenses wide open (the 50mm is f1.4 for example). The old lenses are also better resolution and higher contrast than the new ones I have. In fact I found the 50mm to be favourite for these shots, the 35mm and 28mm were a bit too wide. I did not get a chance to try the 135mm Vivitar entirely as the first attempt did not go well and then the weather got nasty on me so I couldn’t make changes to the methodology and try again.
One thing was common across all: there was no way I could see to frame the shots, either with the optical eye-level finder or the LCD screen. I literally looked up at the sky, pointed the camera (on tripod of course) in approximately the same direction, and pushed the button. By the way, it helps to use the self-timer on short countdown to eliminate camera wiggle when you do this – although the very long times mean any initial shake has minimal effect and the timer trick works better for slow-speed shooting (1 sec to 1/60) rather than long exposure (over 1 sec).
Now here’s the thing. There are three different ‘realities’ in photographing the stars like this. The first is what you see with your eye. Up here at 3200 feet of elevation when our skies are clear they are very clear and we can see a lot of stars, even if we are freezing while gazing. In fact in daylight our skies are extra blue and the colour temperature needs adjusting to get the white balance right; auto or daylight settings won’t be right.
The second reality is what the camera ‘sees’. Since it can accumulate light over time, which eyes can’t, it can pick up fainter stars that we won’t see. It can also detect near-infrared and ultraviolet to some extent which adds to the starlight potential.
The third ‘reality’ is the unreality of what the camera reproduces. High ISO and long exposure both add noise to the image, making it full of ‘stars’ that aren’t really there but are just in the camera’s ‘imagination’. The Canon has noise reduction settings for both high ISO and long exposure time. I find them not terribly effective, to be honest. They do slow down the image processing time, making for quite a wait before you see what you’ve got. As it was I used ISO 800 as a maximum because I couldn’t stand the extra noise that is generated by the higher sensitivities; not worth it for a couple of extra stops exposure. Even ISO 400 contributes a noticeable amount of noise even with reduction turned on.
But this doesn’t matter! In fact I was not going for pictures representing what the sky looked like to the eye. Instead I wanted images that appear to have been taken with the Hubble Space Telescope of distant galaxies that our eyes will never see. I think the results are not disappointing.
That last one is, I feel, the best.
How much of it is really stars and how much camera noise? I don’t know. And frankly I don’t care. I like the end results, and that’s what matters.