This is the first official post in my new blog series of DSLR Photography. Yesterday was an intro to the first "chapter." You can find that here: DSLR Photography Basics: Intro to Shutter Speed, Aperture and ISO. This is going to be a decently long post because I have a lot of "pre-basics" to cover before I actually touch base on todays topic, Shutter Speed. I will be explaining exactly how your camera takes a picture, what the basic parts are called and how they opperate. I am writting this as I would have liked to be taught. The only teaching style I am familiar with is the one that works for me, so that is what I will try and portray to you. After we get through the cameras operation I will give a breif explanation of Exposure before we get to the good stuff. Who am I kidding? It's all good!
Alright. You are hear to learn how to control your camera in effort to take great pictures. To do that we need to learn exactly what each of those settings are changing. You are about to do just that. The image below is scanned out of David Busch's Canon EOS 60D Guide to Digital SLR Photography (I highly recommend this author). The Canon EOS 60D is my specific camera. Your camera may be a different model or brand all together but DSLRs all work in the same general way so this will apply to you no matter which DSLR you own. It will be intimidating to take in all the different parts but be patient, read slow and I will do my best to explain it to you in terms you can understand. Take a second to look over the diagram and check out the different parts along with their labels. You can click on the image to make it larger.
Okay, do you feel just a little familiar with whats represented up there? Don't be ashamed if you're completely lost. I'm going to try and fix that. I am not going to cover everything mentioned up there as it isn't important at this point in our lessons. I'm just going to review the basics and I will continue with the rest when we get that far into it. Worried you, didn't I?
For starters let me just say that an image is nothing more than recorded light. That's it. There is no magic behind it. The light bounces off objects (friends, family, flowers, cars... anything you're taking a picture of) refecting the light into the lens of your camera. Your Sensor (#11) is what records that light. It is protected by your Shutter (#10), which opens and closes to control how long the Sensor is exposed to the light. Your ISO (a camera setting) determines how sensitive your Sensor is to light. You can control the Shutter by adjusting your Shutter Speed and you can control your Sensor by adjusting your ISO levels. Simple enough, right? Now lets add one more thing to the mix.
The lens you attach to the front of your camera controls light as well. In your lens there is a collection of disk-like slides that can be adjusted to let in more or less light at a time. The image below shows you those disks. These are referred to as your Aperture Ring.
(Photo borrowed from ShutterStock.com)
Before we continue lets recap just a bit. When light enters your camera it first goes through your lens and Aperture ring, then reaches the Shutter, and finally your Sensor. Your Aperture will limit the light allowed to enter into the camera. Your Shutter controls how long that light comes in contact with the Sensor. Your ISO controls how sensitive it will be to the light. Amount, Time, Sensitivity.
Ready to move on? Good. If you get lost with anything mentioned just leave me a comment and I'll get back to you. Remember, I'm no professional. I am a beginner learning just like you. If I don't know the answer to your question I will try and find it but I will not lie to you. That helps no one. :)
EXPOSURE. Exposure is the term used to discribe the lighting conditions in a photograph. The lighting controls (as mentioned above) are simplified by saying it's Light, Time and Sensitivity. That is what makes up the exposure of any photograph.
If a photo is too bright it is referred to as "over exposed," as too much light has reached the sensor. That could be caused by a wide Aperture, a long Shutter Speed or a high ISO.
If a photo is too dark it is referred to as "under exposed." This could be due to a narrow Aperture, a short Shutter Speed or a low ISO. We will get more involved in each of the settings in the rest of this chapter. For now let's concentrate on today's topic...
Here is where we get into the more complicated stuff. Are you ready? Good! If you want to experiment while reading this grab your camera and set it to the appropriate mode. It is usually on your Mode Dial on the top of your camera. It is either labeled with an S or Tv for Shutter Priority (this allows you to control the Shutter Speed while your camera controls the rest of the settings), A or Av for Aperture Priority (allows you to control Aperture and the camera controls the rest) or M for Manual mode if you want to control it all. Manual also allows you to set ISO to Auto or you can control it yourself. Consult your manual for changing the values, it varies per camera but by selecting the right Mode, you will most likely be able to figure it out by messing with it for a minute. Shutter speed is measured in seconds ranging from a fast 1/8000th of a second up to a slow 30 seconds. Aperture is displayed as f/1.8 - f/32. ISO displays as a whole number ranging from Auto, to 50-6400. (Ranges vary, this is an example based on the specs of the Canon EOS 60D.)
APERTURE. Aperture controls how much light is allowed through the lens and into the camera. This is the first form of control light encounters on it's way to your sensor. Aperture on your camera is set in what is called "f-stops." It's displayed as f/1.8, depending on your setting. The smaller the f-stop, the larger the opening of your Aperture ring, allowing more light to enter your camera. The smaller f-stop also gives you a greater sense of depth of focus by allowing just your subject to be in focus while the background is blurred. With a larger Aperture your Aperture ring has a smaller opening, letting in less light and giving focus to more of your image. Here is an example.
As you can see in the image, the more you increase your Aperture, the more your background comes into focus. Cool, huh? Usually I would move onto Shutter speed next as it's the next form of control light encounters, but I have a surprise for you there and that has to wait until last. :) On to ISO.
ISO. ISO is the setting that controls how sensitive your sensor is (the device that actually records the light, making a picture) to the light that you allow to reach it. It usually starts at 50 or 100 (depending on your camera settings) and can go as high as 6400 or 12800 depending on your camera and optional add-ons. The lower the ISO, the less light your sensor records. The higher the ISO, the more light your sensor records. Simple enough? When working with ISO I would always start out as low as possible and increase it as needed but only after exhausting your efforts with Aperture and Shutter Speed. I will explain why after you check out the image below.
Blow it up if you need to by clicking on it. The purpose of this demonstration was to show you how the higher ISO levels increase the graininess in the image. Settings were adjusted to keep the exposure level for each of the images the same. This is why there is no difference in lighting. Also, the "800" was shot a tad out of focus but it has nothing to do with the ISO itself. If you look closely at ISO level 200 and ISO level 1600 you will notice 1600 has more pixelation. It looks a little rough. This happens little by little as you raise your ISO and you may not notice it until you load the pictures on your computer and blow it up for use as a desktop background or other such things. Just something to keep in mind when wanting crisp, clear images.
APERTURE. Aperture controls how much light is allowed through the lens and into the camera. This is the first form of control light encounters on it's way to your sensor. Aperture on your camera is set in what is called "f-stops." It's displayed as f/1.8, depending on your setting. The smaller the f-stop, the larger the opening of your Aperture ring, allowing more light to enter your camera. The smaller f-stop also gives you a greater sense of depth of focus by allowing just your subject to be in focus while the background is blurred. With a larger Aperture your Aperture ring has a smaller opening, letting in less light and giving focus to more of your image. Here is an example.
As you can see in the image, the more you increase your Aperture, the more your background comes into focus. Cool, huh? Usually I would move onto Shutter speed next as it's the next form of control light encounters, but I have a surprise for you there and that has to wait until last. :) On to ISO.
ISO. ISO is the setting that controls how sensitive your sensor is (the device that actually records the light, making a picture) to the light that you allow to reach it. It usually starts at 50 or 100 (depending on your camera settings) and can go as high as 6400 or 12800 depending on your camera and optional add-ons. The lower the ISO, the less light your sensor records. The higher the ISO, the more light your sensor records. Simple enough? When working with ISO I would always start out as low as possible and increase it as needed but only after exhausting your efforts with Aperture and Shutter Speed. I will explain why after you check out the image below.
Blow it up if you need to by clicking on it. The purpose of this demonstration was to show you how the higher ISO levels increase the graininess in the image. Settings were adjusted to keep the exposure level for each of the images the same. This is why there is no difference in lighting. Also, the "800" was shot a tad out of focus but it has nothing to do with the ISO itself. If you look closely at ISO level 200 and ISO level 1600 you will notice 1600 has more pixelation. It looks a little rough. This happens little by little as you raise your ISO and you may not notice it until you load the pictures on your computer and blow it up for use as a desktop background or other such things. Just something to keep in mind when wanting crisp, clear images.
SHUTTER SPEED. Shutter Speed controls how long the light hits the Sensor while taking a picture. The longer the Shutter is open, the more light that is allowed in. With more light, there is a brighter picture. This is a very useful feature to have in low light conditions. Granted, while using a long Shutter Speed it is wise to use a tripod. Even with the steadiest of hands it is impossible to get a sharp image using slower speeds. To show you more of how the speed effects the motion blur of an image take a look at the picture below.
Picture borrowed from FreeDigitalPhotographyTutorials.com)
The pin wheel was spinning in all three of these pictures. Taking a picture of a moving object at a fast Shutter Speed will freeze it in action. The first pin wheel demonstrates this. Setting a long Shutter Speed will allow for the motion of the object to show through creating a motion blur like the last pin wheel. Setting a medium speed will show a blur but it won't be as harsh, as demonstrated by the second pin wheel. The speed settings will vary depending on how fast your subject is moving and the type of blur, if any, you want to achieve. Now lets show you it's effects on lighting...
(Picture borrowed from Mansurovs.com)
The first picture was taken with a faster speed (1/100th of a second) than the second (1/2 a second). See the difference? This is great for evening or moon shots. You will need a longer Shutter Speed to absorb the light and details of the moon. A decent zoom and tripod is definitely needed for this though. But once you get the picture you want it was so worth all the hassle!
Want to see something fun that you can do with long Shutter Speeds? It's called "painting with light" and just so you can't say I didn't warn you... it's highly addicting. So grab a flash light or some sparklers and set your camera up on a tripod with a high Shutter Speed. Click the shutter down (take a picture) and while the Shutter is open for whatever length of time you chose, hop out there in front of the camera and start drawing with your light. Here are some examples...
Fun, huh? Now you're going to get out one night and try this, aren't you? Yeah, that's what I thought. Go practice those skills! But before you leave let me cram in just a little bit more info on Shutter Speed...
As you know by now, once light enters your lens it is heading straight for the sensor. Without the Shutter Curtain controlling how long the light comes in contact with the Sensor you would end up with a solid white image everytime. The Sensor is made up of (in my case) over 900,000 pixels. Each of those pixels absorb the light that reaches it. If the light is left to continuously expose the pixels ultimitely the pixels will "fill" with light and "flood" onto a neighboring pixel until there is no color left at all, just an over abundance of white light. This is from having too long of a Shutter Speed, causing over exposure.
Note: When strong light is exposed to the sensor for long periods of time (like staring straight into the sun) it is bad for the Sensor. When you take pictures using the LCD to frame and compose your shots (also known as Live Mode) you are allowing your Sensor to be directly exposed to that light the entire time. If you take pictures using your View Finder instead, the light is reflected to a prism (#3) and then to your View Finder (#5), completely passing the Sensor until you are ready for your shot to be taken. When using the View Finder, once you press your shutter button and take a picture your camera flips up it's mirror (#9) allowing for the Shutter and Sensor to do it's job. While in Live View mode, the mirror is constantly up giving you a "what-you-see-is-what-you-get" view due to the light directly hitting the sensor instead of going through a series of mirrors and prisms; hence the term Live View.
----------------------------------------------------------------------
Well, I hope you enjoyed our first tutorial. I know I learned more just by writing down what I already knew. It helped to put things into persective. I also learned that this blog would be much easier for me to handle if I put two or three days into it instead of cramming it all in during 24 hours. What can I say, I'm a Wife and a Mother. My free time is limited :)
