Photography Fun- Night Sky and Exposure Triangle
I think it’s time for another photography fun post. I haven’t spent as much time on my photography as I’d like lately, but I’ve worked on some interesting things. Specifically, I’ve been working on night photography, attempting photographing lightning, and I got myself a tripod! Oh and I learned there is such a thing as an exposure triangle?! More on that in a minute.
Night time sky practice a lot! (Once in a while luck helps out)
Recently I’ve been working on nighttime photography. It’s completely different from daytime. At times in the past I have lucked out with a cell phone on automatic, but I’m trying to get a bit more consistent and purposeful with all of my photography.
First, taking a photo of the moon is completely different than a “moonscape,” or the night sky without the moon. So far I’ve had the most luck with moonscapes, and have managed a clear shot of a few stars in the past. Until recently though I was limited to automatic settings on a cell phone.
Steady hand, tripod, and shutter speed!
Now first, I know the most important piece of low light is a steady hand, or a tripod. I firmly grasp shutter speed. By letting the shutter stay open the camera is allowing more light in. This method also causes blur pretty easily though since it catches any motion of the camera or subjects. Even stars will be blurred if exposure is too long, though taken to extremes this method can be quite artistic. I utilized this setting for some interesting water shots in my other post, explore your space, although this was before I bought a tripod.
This illustrates a shutter speed FAR to slow! Getting better I had a bit of fun with clouds and shutter speed here I was clearly getting a bit bolder here
The other two basic settings a photographer has control over are Aperture, and iso (internal organization for standardization).
Aperture
Aperture is the opening light travels through. Basically how wide the shutter opens. Like when your pupil gets bigger in a darkened room. This is referred to in “F-stops” and the numbers work like wire gauges, where larger f-stops represent smaller measurements. This is because the numbers represent denominators in a fraction. Aperture also affects the way a photo will look as well as how much light is allowed through though.
This has proven a bit harder to learn by feel than shutter speed and affects something called depth of field. A large aperture = a shallow depth of field, or a lot of blur in the background or foreground. I’m still working out how this affects nighttime photography but I know it has a huge impact on my results. It seems obvious that I need it to open wide (small aperture) for the most light, but a larger aperture (smaller opening) allows more depth of field to be in focus. This is the setting connected to a piece of advice I received as a kid with a basic point and shoot camera- “don’t get too close to the subject. Less than about 3-4 feet is too close.”
Great model, and even more practice!
You may be able to see how I was practicing with this idea when I took these photos of a monarch butterfly recently. While I shot these I discovered how to adjust my focus, and work with my aperture at the same time!
This is really my only success in flight. I reduced my aperture to achieve it In this shot my depth of field wasn’t quite right. You can see the butterfly was just a bit closer than I’d have liked
ISO- Internal Organization for Standardization
Back when I received the above mentioned advice, film had iso printed on it. All I had ever been told is that 200 ISO is best for all around day time photography. Film was purchased in even hundreds from 100-400 ISO. On my camera it is measured in “stops” like aperture. There are far more stops available on my camera than I have ever seen offered as film options. I have learned that ISO has to do with sensitivity to light. On a bright sunny day 100 is your best bet, as it gets darker a higher iso choice would be appropriate. As usual though, there is a tradeoff. As you use a higher number ISO the photos get grainier or have more noise. So, you want to use the lowest number you can get away with. I’ve seen several recommendations not to go above 800.
Put It All Together
Now I have to figure out how to put these ideas together with night photography. Like I’ve said it seems a photograph of a landscape, or portrait at night seems to be far less of a challenge than taking a photo of the moon. Though I haven’t gotten what I want in a photo of the moon yet, I do think I understand the nature of the problem. When photographing the moon I am trying to photograph a large light source- but everything else is dark. I have one advantage of photographing the night sky, and only one- I live in a place with very little light pollution. That should allow my camera to focus and receive light where I intend it to rather than random undesired sources.
Photography Exposure Triangle
Another learning tool I’ve discovered is an exposure triangle. It’s a visual aid to understand how these settings work together to adjust your exposure in a particular photo.