Learning to use shutter speed!

One of my earliest memories regarding photography that I can remember is a picture that was on the cover of the El Paso phonebook. I must have been 10 years old or so. It was interesting to me mostly because I had no idea how a picture like that could have been taken. It looked more like a painting to me. It was just a picture of the city shortly after sunset, and from a highpoint, so a rooftop somewhere overlooking I-10 and the Franklin mountain. I know now that it was a long exposure because I remember the light trails from the car lights along the highway, which is what made the most impact for me. Although apparently, it didn't occur to me to look it up! In my defense, I was a kid, and at the time, not everyone had a PC at home, or an internet connection. I sure didn't. So looking it up on google was not an option for me. I also didn't know any photographers I could ask.

Strangely enough, this image made enough of an impact on me that the first day I got the dSLR(after reading plenty of forums and photo blogs in preparation!) I tried to take a picture with light trails from the cars. So I grabbed the tripod, the camera, and went out the first night we had the camera. I was determined to get some trails in my pics and I knew it had something to do with the shutter speed. So I set the camera to 'Tv', which stands for Time Value, meaning shutter speed priority mode(on a Canon, 'S' would be the equivalent on a Nikon). Shutter Speed priority is a form of AUTO, in which you pick the shutter speed(and ISO if it isn't set to AUTO, but we'll get to that), and the camera picks the rest(really only the aperture is left). I setup at the nearest roundabout(I was living in England at the time), and tried it there. I tried 10"(seconds), then 20", then 30". It was EXACTLY what I had been looking for. By picking one simple setting, in this case the shutter speed, I was able to obtain a picture that had been in the back of my mind for many many years! It was very rewarding for me.

Here is one of the test shots that night:

f/13, 30 seconds, ISO 200, 20mm. One of the firsts pictures I ever took on a dSLR. I know the picture isn't much, but I was thrilled at being able to get light trails!

So it turns out that shutter speed is critical in creating the car light trails effect, but that is not all there is to shutter speed of course. You don't always want trails, and you don't always want a long exposure. I would say that once you can no longer hand hold an exposure, it would be fair to call it a "long" exposure. The easiest way to experiment with shutter speed is to set the camera to 'Tv'(on a canon, 'S' on a nikon) and see what different shutter speeds do. Here are some quick guidelines for what certain shutter speeds are good for:

*A guideline for the slowest shutter speed you can hand hold is:

     Limit for hand holding a shot = 1 / focal length you are shooting at
 
It is just a guideline, but it gives you an idea of what you can expect to be able to hand hold and still get a sharp picture. Some lenses have  IS(Image Stabilization,) VR(Vibration Reduction) on nikon lenses, which counter acts the shake, and allows you to shoot at slower shutter speeds and be able to hand hold the camera. Very useful nice to have.

**There is a guideline for how long that actually is:

      Max exposure before trails = 600 / focal length
 
Again, just a guideline, but it gives you a good starting point or limit if you want to avoid star trails when photographing the night sky. 

So there is a really basic summary of uses for certain shutter speeds. Here are a few examples, with images I have taken:

f/18 @18mm, 30 seconds total exposure(Stacked from 3, 10 second images)

f/2.5, 1/5000, ISO100, 50mm

f/2.0, 50mm, 1/80sec, ISO 400

f/3.5, 45 seconds, ISO 1600, 8mm fisheye

f/3.5, ISO 3200, 8mm fisheye, 3 hours total exposure(stacked from ~200 individual images)

f/11, ISO 100,  25mm, 2 seconds(I should have probably used a faster shutter speed)

This is all just a guide to give you a rough idea of where to start. I can write about it all I want, but it really comes down to you getting out there, setting it to Shutter Speed Priority ('Tv' on a canon, 'S' on a Nikon) or manual, and seeing how it affects your pictures.

Glossary

First, I will define some photography terms that will probably be used often in this blog. Don't worry about memorizing them now, we will mention them so much that it should become second nature to you at some point.

Disclaimer: I am trying to keep things simple, so if you want a more technical definition, this is not the place. I don't think that at this point it really adds to the discussion to get very technical.

Aperture - Basically, the size of the opening in the lens. This can be controlled(up to the lens' maximum and minimum apertures). It is written down as a fraction, such as f/1.4, f/5.6, f/8, f/11, etc. Since it is a division, the larger the f-number, the smaller the aperture(opening) and the less light it lets in(and the more DOF). So try to remember the smaller the f-number, the bigger the aperture. It is an inverse relationship.

Depth of Field(DOF) - In the photograph, the distance range that is in focus. Aperture and focal length have dramatic effects on DOF.

Exposure - A term for the amount of light that you allow to hit the film or sensor of the camera.

ISO - The level of sensitivity to light of the image sensor or the film. The higher the ISO, the more sensitive it is. Fun Fact: The initials come from the International Organization for Standardization, but they aren't really initials, and come from the Greek word for equal.

Focal Length - This has a somewhat complicated technical definition. For our purposes, suffice it to say that it is the number on your lens that is measured in millimeters(mm). Not the filter size, but the main specification of your lens. 18-55mm, or 50mm, or 70-300mm. That would the focal length. The smaller/shorter it is, the wider the angle of view. The longer the focal length, the more "zoomed in" it is. Most dSLRs come with what is known as a "crop sensor", or APS-C size sensor, meaning it is slightly smaller than the 35mm full frame sensors of the higher end "pro" cameras. This means that in some lenses, such as the very common(and awesome) nifty 50, the Canon EF 50mm f/1.8 II are actually about 1.6 times the focal length they say on there. So this lens would be 80mm on these cameras.

Live view - A feature on many dSLRs that allows you to see the image BEFORE you take it on the LCD display. Very useful for certain types of photos. If you had a point and shoot previously, or even saw one, you should be familiar with this as this is the ONLY way you can see what you are taking in most point and shoots, since they don't have an optical viewfinder(some have a digital one, which is kind of strange).

Shutter Speed(exposure time) - The amount of time that you let light hit the sensor or film. Measured in seconds. Usually denoted as a fraction when it is less than 1 second(1/500, 1/50, 1/6, etc.) and with a quotation mark when more than 1 second(1", 10", 30", etc.).

Viewfinder - Where you put your eye to see what the picture will look like. On dSLRs, it is optical, and what you see is what you get(for the most part).

White Balance(Color Temperature) -  Refers to the the adjustment of color mapping in order to render color tones correctly under artificial or different lighting(such as incandescent or fluorescent lighting). It can be done by choosing a preset(such as daylight, cloudy, color temperature, fluorescent, etc.) in camera or in post processing software(such as DPP, Aperture, Lightroom, Photoshop, etc.).

As I remember more terms, I will add them to this entry so you can reference it as needed as well as define them as they come up. Again, don't worry if this seems daunting or overwhelming, it will all fall into place.