Shutter speed or exposure time is one element of the photography exposure triangle, the balance between shutter speed, aperture or lens opening and film speed or ISO. To get the camera sensor to record an image a certain amount of light needs to be let into the camera. Shorter shutter speed darkens an image but causes less blur. A wide open aperture lets in more light but causes a shallow depth of field, and a high film speed or ISO allows an image to be recorded faster but creates more noise or “grain”. Photography is a compromise between these three elements.
This exercise is about deliberately exploring photography with different shutter speeds. It is about recognizing opportunities for freezing action as well as exploring the beauty of motion blur, and all the nuances between the two extremes. In the text below I am going to try to show the process of how I choose the subject, then work the three main camera controls, shutter speed, aperture and ISO, and finally how I do the post processing.
Aug 7, 2017 Bicycle Path just north of Fort Calgary site
We went out for some practice with our new 6 stop neutral density filters. These filters reduce the amount of light coming into the lens substantially, the glass looks like sun glasses. This allows for much slower shutter speeds in bright sunlight. The idea was to photograph the motion of bicyclists, while following them in a panning motion. The camera was handheld with elbows tightly held against the chest, and the rotation was from the hips. Shutterspeeds were between 1/15 and 1/30 of a second.
I like this picture as it gives a feeling of motion in both the background and the cyclist. With post processing in Photoshop I got some interesting effects.
Long time exposures allow you to actually “paint” with light. Here is an extreme example
May 12, 2017 Assignment
Frank Lake Cargill discharge channel
To open a larger map of the lake in a separate browser window click here.
The object of this assignment was to photograph birds in flight with different shutter speeds. Frank Lake is great place to photograph birds, and I find it especially rewarding in the area along the Cargill discharge channel. Especially in the morning before noon when the sun is more or less in your back. This is not the case when trying to photograph from the proper blind to the east. You typically end up photographing backlit birds in flight.
We arrived around 10:30 am, and observed a strong flow at the Cargill discharge into the lake. Several Common Terns were hovering and diving into the channel. Small fish must be frequenting this area, probably because of the rich nutrients in the Cargill discharge. The lure of an easy meal must be strong enough for the Terns to ignore photographers. We were able to observe them flying back and forth along the channel and witnessed frequent dives into the water.
It takes a bit of practice to follow these birds with a telephoto zoom lens. My lens was set at about 200 to 300 mm.
As they were flying in from the south end of the channel, I peeked above the camera along the barrel of the zoom lens to line the bird up, and then with the zoom at approximately 200 mm would I would quickly move my eye over the viewfinder to “catch” it in the view finder. By holding the “back button focus” button and having the focus setting on “continuing focus” (for Canon users AI Servo AF)
I was able to follow the bird in the view finder while the focusing engine kept the image sharp. (I love back button focusing since hearing about it from Bill this last winter course). In this mode the image is almost always sharp as you swing the camera around. This way you can decide when to trigger the shutter.
The objective of this assignment was to use different shutter speeds to explore different aspects of motion blur. A fast moving subject completely “frozen” is OK for some situations, but from an artistic perspective some motion blur elevates a picture to another dimension. I enjoy a hint of action, something unpredictable that could happen any moment, a feeling of anticipation. By slowing the shutter speed down I got the body sharp but the wings slightly blurry. I tried to follow the birds as they dived into the water while holding the shutter down in continuous mode. But all of them were “flops”. The action was just too quick for me. Maybe by scaling back the zoom factor would I have been able to get something decent, but that thought never occurred to me in the heat of the moment.
So below are some of the “almost got it” flops.
Here is another “almost got it” flop. This picture was an attempt to get motion blur in the background while keeping the bird sharp. I find these type of dynamic pictures exciting as they give a real feeling of speed and action. In this case I liked the fact that the Tern actually got its meal. I triggered the shutter too late. The bird had gained too much altitude and was halfway up between the island shore and water behind it. My reactions and the continuous shutter speed of my camera are too slow. An then there is always a certain amount of luck required for exceptional pictures. It takes time and patience!