Foundation: Light Buckets

Welcome back!
So to begin in photography, you need a firm understanding of how light is being captured and how image data is being stored in their digital home. When ever you take a picture, the digital data that represents the light values of each pixel, are stored in one of the many file formats. The light values stored in these files can be viewed numericly or visually by pixels on your screen, more on this later, but first –  let’s get the file types out of the way.

DigitalSLR – RAW file – stores the most light data without tampering with the information (hence the word RAW…)

Standard digital camera’s – JPEG – stores a decent amount of data but has been tampered with and contains file compression (loss of data, remember… data = light, light = details).

I wont go into much about film here, but you should do some study on film cameras or more specifically the capabilities of film, surprisingly film has amazing potential over digital cameras…  it’s advantage over digital is how much light you can capture in one shot. But more on that in later posts.

Most digital cameras now a days have the capability of capturing 6 stops of light. What are stops!?!? Stops are a term used by photographers to help reference how much light is entering the camera. Think of a bucket of water as a stop, and – refer to the water as light… each camera has 6 buckets of light in which it can fill. There is a bucket to fill for the darkest dark tones or, areas of an image which is giving off small amounts of reflective light. Than a bucket for the shadow darks, than a bucket for the shadows, than another bucket for the highlights – a bucket for the bright highlights than lastly a bucket for the brightest highlights.

Now what’s interesting is not all these buckets necessarily have to be filled and sometimes your buckets will overflow. The amount of water in each bucket is determined by the scene in front of you. If you’re starring into the sun with your camera, your going to have massive amounts of water in your highlight bucket, what happens if that bucket overflows? Your highlight water will seep into the adjacent buckets used for highlights(bright light). But what if those buckets are already full? You lose the light quality because all your buckets are overflowing. Highlight detail doesn’t belong in the shadow buckets(remember that detail is considered light based on the idea that detail is made up of bright/dark pixels resting next to each other). Trying to keep this short and sweet but – the idea I’m trying to get across here, is the fact that there will be scenes which you wont be able to capture because digital camera’s are simply not advanced enough to capture all the light in one exposure.

So what do you do?!?!? You have many choices: A.)Make the sacrifice and capture the detail in the highlights B.) Capture the detail in the shadows and lose the highlight detail C.) OR! Apply a plethora of camera techniques to get all the light! HDR Blending, Gradient filters in front of the glass(lens),push/pull processing in lightroom/photoshop etc.

What I revealed is a big big secret to how some of the big dogs in the photo community manage to make absolutely breath taking images but… I merely hinted at some key points, Now this alone is just a stepping stone of understanding but a very crucial step needed to be taken in the right direction. What comes next is huge, light can be manipulated once it is captured! You can take what’s in your buckets and properly organize your water types into their correct value’d buckets.(some downsides to this, more on that later.)

This image below shows what kind of light is stored in each bucket, It also shows where in the image. In order to capture and re-create the scene you saw in person you must understand where the light values in your scene should go in your camera… If you are ultra-fledgling and this is over your head already, understand that, -before you can capture realistic images, you need to be able to recognize values in the scene in front of you. You must be able to relate them to this 6stop gradient below before you hit the shutter. If done incorrectly, you wont be able to get all the details to  re-create that realistic image, or exact representation of what you saw in person.

light_bucket_example

So what does this light look like numerically? Here is the data values of each pixel and it’s brightness levels of each pixel below. The little graph below is displayed on the back of your camera while using most cameras… its 2016 people, if you don’t utilize the histogram, your shooting yourself in the foot and gambling with your exposure. More on this in later posts, remember photography is subjective so don’t get caught up on understanding this concept fully. It will all make sense later.

Histogram1

To better explain this histogram, let me label it.

Histogram2

Light = L, again light = detail. This white hilly graph is representing how much detail is contained within each light ‘Value’. Dark values are to the left of the graph, Bright values are to the right. Mid-tones are found in the middle of the graph, values that are bright but not to dark. At the top I’ve labeled the histogram to better represent the stops in which light is registered into the camera.

As you can see, looking at the photograph above, it’s relatively dark in the bottom portion of the image, more so than it is bright. So looking back at the histogram again, you can see how the light data is represented on the graph. There is a bigger hill to the left than the right. Each image will have a different looking graph but essentially the idea is to have the proper water qualities in there corresponding light bucket. If you go against this rule, you will stray away from what looks proper and realistic to fantasy land. Art is subject and fantasy land is okay, as long as you don’t over do it. Strive for realistic light!

This is just the tip of the iceberg and hopefully I haven’t lost you in the rabbit hole yet.
Stay tuned for the iron triangle of exposures and a technique known as push/pull processing. We will be getting into the meat and potatoes of photography called “post-processing” the stuff you do after you take an image. I wont go on about how to change camera setting and how to operate a camera because that stuff can easily be learned on the internet. To continue from this point, It is recommended you have a copy of Adobe lightroom and photoshop. If you plan on getting serious with your photography, sign up for adobes photographic software made for artists. If you really don’t want to purchase software to advance your photography than I’d say your crazy! Software for photography is dirt cheap and is better to invest in software than that next 5000$ camera or 1000$ lens…maybe get that 500$ Digital SLR because your going to need one to be able to utilize the next section. 😉

6stops

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