Photography Basics - Part 1 (The Basics of Exposure)
The Basics of Exposure[/SIZE][/U][/B]
So you bought a DSLR, but you still leave it in AUTO mode? You are greatly limiting your own creativity and the camera`s abilities by simply resorting to Auto mode for your photos. It may be a bit overwhelming at first, but photography is pretty straight forward... you just need some practice and patience!
Photography is a big part of my life and is something I LOVE to use in my detailing work. In fact, it makes my detailing work a lot more enjoyable.
Photography is a great hobby for anyone to get in to, and it is something that you will find fun and interesting. You will be able to incorporate it in just about anything you do if you would like.
It seems the majority of DSLR owners shoot in AUTO mode... this is the first thing that needs to change! Many people expect miracles when purchasing a higher end DSLR, but in reality, there is much more to it than having a "nice camera".
Learning how to control your images through understanding the basics of exposure is key to improving your images and making them look the way YOU want them to look and not how your camera thinks they should look. Your camera can do a fantastic job estimating proper exposure under normal conditions, however in detailing, you are often taking pictures of areas that incorporate intense lighting on a dark surface and that can cause some serious issues in Auto mode... but we will get to that later.
Before we even consider photographing anything specific, like cars, let`s talk about the 3 basic settings of exposure... these are the 3 main settings your camera is choosing for you when you have it in auto mode (there are many other settings to learn and explore in your camera, however these are the 3 that directly impact the exposure of the image)... you may have heard of, or seen these settings on the camera before.... Aperture, Shutter Speed, and ISO.
Aperture - The aperture of your lens is essentially a circular opening inside of the lens that gets bigger and smaller in order to allow more or less light through the lens and onto the digital sensor. You can think of it much like the iris in your eye. This setting controls what is known as the `Depth of Field` (DOF for short). As you may have guessed, this controls how much of your image is in focus... if you have a shallow depth of field, there will be a small amount of the image in focus and vice-versa. Aperture values are measured in "f-stops", you may see aperture values displayed as f/5.6, for instance. (I can explain the reasoning behind this if you are truly interested). The aperture value has an inverse relationship to the amount of light that is entering your camera. Smaller numbers (f/2 for example) allow more light into your camera as the aperture is opened more than a larger number (such as f/8).... now DOF is also affected by such variables as focal length of your lens and the distance from your camera to your subject, but we will not talk about that just yet as they are not too important in understanding the basics.
Lenses with larger apertures (smaller numbers such as f/1.8, f/2.8) are typically more expensive and are more desirable because they allow much more light into the camera which makes them excel in low light situations. The shallow DOF associated with these larger apertures is also desirable, as the out of focus (or blurry) background adds a nice touch to portraits and still life shots because they allow you to isolate your subject from the background.
Here are some examples that display different DOF`s. (click on the images to view them larger on Flickr... if you right click on the image in Flickr you can choose an even larger size to view)
http://farm9.staticflickr.com/8236/8...e652a1c03a.jpg
New Puppy - Tucker by zmcgovern45, on Flickr
^This shot is one I took of my friend`s puppy. Notice how his eyes are very sharp and in focus, but everything else immediately starts to fall out of focus. This is due to the shallow DOF created by shooting at an aperture of f/3.2. This is an excellent effect for shooting portraits because it draws the viewer right into the subjects eyes and does not distract them with objects in the background. You`ll notice in most pictures I take of cars (full shots, not details) that the entire car and most of the background is in focus, this is because I use smaller apertures to ensure that the entire car is nice and sharp looking (typically around f/8-f/11).
http://farm3.staticflickr.com/2844/9...36ccea8a5e.jpg
Honeymoon by zmcgovern45, on Flickr
^Another example of shallow DOF. This was shot at f/2. Notice how the background is totally out of focus, eliminating any distractions from the scene and allowing the viewer to focus solely on the subject of the scene.
Shutter Speed - As suggested, this is how fast your shutter opens and closes. A faster shutter speed allows less light to reach your sensor than a slower shutter speed does. The shutter speed controls the amount of motion blur in your images. For instance, if you are shooting sports you will want to use a fast shutter speed to freeze the action. If you were to use a slow shutter speed while someone is running past you, their arms and legs and any other moving parts would look blurry. You also need to consider that if you are using a slower shutter speed, your images may be blurry due to your hands shaking while holding the camera. Many lenses/cameras try to compensate by utilizing vibration reduction (VR) technology, but you should still be aware of the possibility of introducing `camera shake` into your images. If slow shutter speeds are necessary, a tripod is a crucial tool to avoid camera shake.
http://farm8.staticflickr.com/7042/7...afa8a9e61c.jpg
Chicago Invite 2012 by zmcgovern45, on Flickr
^This photo was taken with a shutter speed of 1/1000th of a second, which is common for action shots. You can see that the scene is completely frozen in time, no motion blur, which is what I was wanting for shooting sports.
Often times for detailing shots in a dimly lit garage, I have my camera set on a tripod and use slower shutter speeds to allow for a decent amount of light to come in.
http://farm3.staticflickr.com/2807/9...494304ae81.jpg
Honeymoon by zmcgovern45, on Flickr
^This photo was taken with a 30 second long shutter speed... so obviously a tripod was needed! You can get some amazing images at night with a tripod. This dock was completely pitch black. You will notice how the water looks totally smooth even though there were constant waves crashing on the beach... the slower shutter speed allowed the movement of the ocean to blur together and looks totally smooth.
ISO - This is a bit different from the other 2 settings. Aperture and Shutter speed are mechanical settings that control the way your camera functions in order to allow more or less light to reach your lens... ISO is a digital setting. ISO is essentially the sensitivity of your sensor to light. Let me explain... if you are outside in bright sunlight, there is more than enough available light for you to use just about any setting you want. If you need a fast shutter speed, you need a good amount of ambient light because the quick shutter speed will not be exposing the sensor to light for very long. If you are indoors with considerably less light, but need a quick shutter speed the first thing you would do is set your aperture setting to where you think you want it (depending on how much in focus area you want) and then see what your meter is reading... chances are it is telling you that your image will be underexposed. So what can you do if your aperture is opened up (to allow as much light as possible) and your shutter speed is where you need it to be (to reduce motion blur caused by a moving subject), but you have no more light? ( ...you could add a flash, but let`s pretend that is not an option...) Increasing your ISO makes your sensor more sensitive to the available light, therefore the dimly lit room is now more "bright" as far as your sensor is concerned. There are some trade offs though... lower ISO produces cleaner images, while higher ISO produces grainier images. I`m sure you have noticed that if you take photos indoors, some of them appear quite grainy if it is particularly dark... this is due to the fact that your camera automatically bumped up the ISO setting to compensate for the low light environment.
http://farm3.staticflickr.com/2841/9...6041410fa7.jpg
Our trip to Okoboji, IA by zmcgovern45, on Flickr
^This image was taken at a relatively high ISO setting of 2000. The small image here looks very good, but if you click on the image to go to flickr, then right click and view at the original size, you will notice a good amount of noise. This is the trade off you have to make in order to shoot in very low light. Despite how bright it looks in the photo, this was taken in a very dimly lit room at a winery. It was taken at a wide open aperture of f/1.8 also, to allow for the most light possible while still allowing me to freeze my subjects and eliminate motion blur with a shutter speed of 1/60 second (the slowest I felt comfortable using in order to maximize light).
Summary
Aperture - Controls Depth of Field (DOF)
- Smaller # = More Light = Shallower DOF (ie f/2.8 allows more light and has a smaller depth of field than f/8)
Shutter Speed-Faster Shutter Speed Freezes Motion
- Slower Shutter Speed can cause motion blur if shooting a moving subject
- Tripods are great for slower shutter speeds
ISO
- Controls your sensor`s "sensitivity to light"
- Higher ISO results in more grain (aka digital noise)
- Always want to use the lowest ISO as possible to reduce noise
Alright... I know that was probably more than you were hoping to read right now, but PLEASE DON`T GET DISCOURAGED! This will all become second nature to you soon enough, you just need to play around with the camera so you can see these changes for yourself.
There are several other modes in your camera that you need to learn to use. Set a goal for yourself, don`t use Auto mode ever again!
Some "semi automatic" modes are known as: Aperture Priority Mode and Shutter Priority Mode. These are FANTASTIC modes for having more control over your images!
Aperture priority mode allows you to set the aperture and ISO and allow the camera to choose the shutter speed that it thinks is best for a proper exposure.
Shutter priority works the same way except you are choosing the shutter speed rather than the aperture.
These modes are fantastic, however there is still much more that you can get by learning to use `Exposure Compensation` in these modes, or taking the full plunge and switching to full manual mode (which I recommend eventually).
I HIGHLY ENCOURAGE YOU to get your camera out and just mess around with these settings to see what they do.
Wow, I could obviously write a novel on this, but I am going to have to cut myself off for now since I am supposed to be working :/ (don`t tell my boss!)
I will eventually get around to doing several other threads similar to this that will help to cover other basics of learning photography.
-Zach
Re: Photography Basics - Part 1 (The Basics of Exposure)
I wish my pics came out looking this good. Mine look like a drunk took them :crazy2:
Re: Photography Basics - Part 1 (The Basics of Exposure)
You`ve got to have the right gear and know how to use it :)
Re: Photography Basics - Part 1 (The Basics of Exposure)
Zach -
Thanks for the posts with your Details and especially thanks for taking the time again, to post up some really good info on camera use in all types of conditions.
This is as good as taking a class - thank you so much !
Dan F
Re: Photography Basics - Part 1 (The Basics of Exposure)
Quote:
Originally Posted by
zmcgovern45
You`ve got to have the right gear and know how to use it :)
Someone else told me that once before :hmmm:
Re: Photography Basics - Part 1 (The Basics of Exposure)
Re: Photography Basics - Part 1 (The Basics of Exposure)
Thanks for posting this. I read it a few weeks ago and have now been shooting all defect photos and 50/50 in manual. The only thing I use full automatic for now are showing gross before and afters on like wheels and engine bays.
Re: Photography Basics - Part 1 (The Basics of Exposure)
This is really well explained. I think I take the big step and change my camera from Auto mode and play around with the settings. Thanks.
Re: Photography Basics - Part 1 (The Basics of Exposure)
i too am an amateur photog buff and i prefer shooting in manual mode as you can control how your pics look much more easily. especially more static objects like cars or my preference, landscapes. nevertheless you`ve explained the most important parts of photography in a language the most beginners would understand and i thank you for that. so get yourself a decent slr and the most important thing is the lens you use on it. happy shooting everybody.
