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So… It’s Christmas morning and your Significant Other has bestowed upon you the latest and greatest, most powerful, highest megapixel, fastest firing, best low light performing conglomeration of buttons and dials the world has ever known. Or you’ve had your camera for a while and are ready to progress to the next level and get out of the Full Auto mode. Or you are comfortable shooting in manual and just want a quick refresher. Whatever the case, the topics we will be covering over the next few days should help get you up and running with shooting in manual mode and understanding the basics of light.

Let’s jump right in. Grab your dslr (or film slr) and put it in Manual mode. If you are not sure how to adjust your mode, consult your owner’s manual (this will be the case with many of the controls I cover, as not only is each manufacturer unique in how the address these controls, many times different models from the same manufacturer will vary widely as well. Essentially, there are tooooooo many combinations out there for me to cover them all in detail). Alright, that’s a big first step. We are now in the world where the magic of photography happens. So let’s take a look around….

In Manual mode, we have 3 main considerations in making an exposure once the light has entered the lens. Can you guess what they are? (Hint: look up at the title ) Yep, Shutter Speed, Aperture, and ISO. Each of these areas control a different aspect of the exposure and getting a proper exposure is a 3-way balancing act. If it sounds complicated, don’t worry. Before you know it, this will all be just like adding 2 and 2, it will be something you just KNOW. But before we can get there, we need to put the time and effort into making all this second nature.

I saw the light…

First up, lets talk a little about light. Photography is the study of light. But Dave, I don’t care about light, I just want pretty pictures of my kids, pets, model train collection, etc. Well, if we look at the science for just a moment, all that we see is a reflection of light. If we look at a white piece of paper on a sunny day, it’s much brighter than if we look at a black piece of paper. All this is true for our camera as well. So to start talking about different amounts of light, we need to give light a unit of measurement and we will call it a “Stop”.  Well, it’s not just us who will be calling it a Stop, everyone does.  From now on, we will talk about adding and removing light by saying things like “Add 2 stops of light” and take out 3 stops of light”.  I am sure this is confusing if you have never seen or heard of any of this before, but stick with me.  It will all start to make more sense very soon.

Now that we know that a Stop is a measurement of light, how big is a Stop? Again, just stick with me here as this will all make more sense once we put it into application but I want you to know the math first.  So…  If increasing light by 1 stop, we double the amount of light we are presently using.  If decreasing light by 1 stop, we half the amount of light we are currently using.  If we are going 2 stops up, we double, then we double again.  If we are going 2 stops down, we half, and then we half again.  And so on…

The 2 important concepts to keep in mind:  Stops are a measurement of light, and when they move, they double or half for each full step.

And now… Shutter Speed!

Shutter Speed is defined as the amount of time the medium (sensor or film) is exposed to the light source and is measured in seconds and fractions of seconds.  The scale of  common shutter speeds, from longest duration to shortest is as follows:

8 seconds, 4 seconds, 2 seconds, 1 second, 1/2 second, 1/4 second, 1/8 second, 1/15 second, 1/30 second, 1/60 second, 1/125 second, 1/250 second, 1/500 second, 1/1000 second, 1/2000 second, 1/4000 second, 1/8000 second, and so on….

The 2 anomalies, 1/15 and 1/125, have no importance other than they make for nice round numbers and make it harder to memorize the scale. If any of you smarties out there know a better answer on this one, I would like to hear it! All research I have done on the subject leads back to just lazy math and no other reasoning.

Hopefully now, those stops of light that double and half when moved are starting to make a little more sense. If we look at the scale, each step down halves the amount of time the shutter is open. Each step up doubles the amount of time the shutter is open. Double and half… Be aware, the scale above is in FULL stop increments. Most, if not all, cameras now use 1/2 or 1/3 stop increments. You still have your full stops (and those are the ones you should commit to memory), you just get extra options along the way for more precise control.

The primary use of Shutter Speed in the exposure equation is to control how much or how little motion blur you get in your images. Take a look at the following 3 images:

(And yes, I know I messed up the perspective on the first one. Don’t shoot me. It doesn’t really affect the example ) So in each of these images, the ball becomes progressively more defined. It is important to note that the ball is in focus in each image. The whole cause of this visual effect is motion blur. So we can see that the faster the shutter speed, the less motion blur captured and the slower the shutter speed, the more motion blur captured. Additionally, I want to point out that each image drops 2 full stops (1/30th, 1/60th, 1/125th, 1/250th, 1/500th). This knowledge will help you predict how much more or less motion blur you will get when making decisions about how far to adjust your shutter speed.

Now then, motion blur occurs at its highest possible amount when the subject is passing the plane of the lens at a perpendicular angle… Huh???? Let me explain a little better with an image:

In the above example, subject 1 will display more motion blur as it is traveling the most distance it possibly can across the camera’s field of view during the time the shutter is open. Subject 2, while traveling the same speed, will display less motion blur as it is not traveling as far across the field of view while the shutter is open. Subject 2, however, does present another challenge, Depth of Field. We will cover Depth of Field in “Depth” in the coming days in part 2 of this series, so stay tuned!

Getting back to today’s lesson, a common term used in conjunction with shutter speed is “Stopping the Action”. This is the shutter speed required to make a moving object appear to be at a stand still and the speed required is always relative to how fast the object is moving. The opposite of “Stopping the Action” if often referred to as “Capturing Movement”. This involves shooting the subject at a slow enough shutter speed to intentionally capture motion blur. This side of the equation is left up to the artist much more than “Stopping the Action” as the amount of motion blur you can get if fairly open. From a slight soft edge up to distortion beyond recognition, the choice is yours.

The following is a list of common situations with moving objects and how to either stop the action or capture movement (and all assume a perpendicular path to your camera, similar to subject 1 in the image above):

Stopping the Action

1. A person standing still – Down to 1/15th second (they need to be really still).
2. A person moving – 1/250th to 1/1000th second.
3. A car passing by – 1/250th to 1/1000th second.
4. Running water – 1/500th second or less.
5. A bird in flight – 1/1000th second or less.
6. A hummingbird’s wings – Less than 1/4000th second (You really can’t capture this scenario with shutter speed alone).

Capturing Motion

1. Running Water/Waterfalls – 2 seconds and up.
2. Cars at night – 8 seconds and up.
3. Fireworks – 1/2 second to 4 seconds.
4. Carousel and other rides – 1/15th second up.
5. Stars at night – Up to hours (accomplished with the bulb shutter speed setting or an intervalometer).

As an example, here is a shot I did a few days ago of a carousel at 1/10 second…

We are about finished with Shutter Speed but one last thing I wanted to mention is “camera shake”, “camera blur”, or just “blur”. This type of blur is different from motion blur. This blur is caused do to the photographer not keeping the camera steady enough for the shutter speed. This effect comes into play mostly at lower shutter speeds but can be an issue at fairly high shutter speeds as well if not careful. The trick to avoiding camera shake is to shoot from a camera support such as a tripod or monopod whenever possible. If you must hand hold your camera, and I know we all primarily do, use the “1 over your focal length” rule. The “1 over you focal length rule” state to never hand hold your shot if the denominator of your shutter speed is less than your focal length. For example, if you are shooting at 60 mm (actual focal length, taking into account any multipliers you camera sensor my add) you should not hand hold the shot if it takes longer than 1/60th second to capture. The same goes true for large zooms. You should not hand hold a 200 mm shot if you have to shoot it at less than 1/200th second. This method is not perfect as you will get numbers between your Shutter Speed settings, so always round to the faster shutter speed to be safe.

And that’s a wrap folks! Today we have covered a lot of ground. We talked about light, stops, common shutter speeds, motion blur, stopping the action, capturing motion, and camera shake. If you have questions, feel I missed a good tip or tidbit of Shutter Speed illumination, or just want to share your thoughts on today’s subject, post in the comments section below. If you enjoyed this rambling adventure, please share it with your friends!

Next time we are going to dive into depths of aperture and it’s “Depth of Field”! So stay tuned for part 2 of Basics of Exposure – Shutter Speed, Aperture, and ISO, coming in the next few days!