Exposure is fundamental to making photographs. Understanding the concept of exposure triangle will make you a better photographer. This simple concept has been talked about a lot of times but rarely do you find a photographer, experimenting and analyzing results based on this triangle.
In this post, we do just that. Whatever you do, don’t skip the assignment.
Today’s Goal: Refresh your understanding of exposure triangle and use the triangle and see its impact.
In one of the most popular photography book, Understanding Exposure, Bryan Peterson talks about exposure in great detail. I am sure you have read about exposure and the triangle in many books.
But have you taken few minutes to understand it by taking action? If you are like most of us, you have not. By reading this concept in books, it may seem very simple, that requires no action, but you will learn more lessons just by taking action.
To understand the concept of exposure, let’s briefly look at how an image is created.
How is Image Created?
A photograph is nothing but an impression created by light on a sensor (or film). If you understand the interaction behind this one simple line, you can make better pictures.
This process of creating an image is very subjective. There is no perfect setting for a certain condition. There is no formula or a “if-then” loop that will answer questions for what aperture to choose?
The image is created when the sensor or film is exposed to the “subject” for the right amount of time with right amount of light coming in through the lens. The right setting is controlled by three adjustments – ISO rating, aperture (f-stop) and shutter speed.
These three elements make three sides of the exposure triangle. These three sides together help you create a good exposure. Exposure for a photograph can be adjusted by changing either one of these three elements.
You can read more about these three elements in our previous post on exposure triangle. In that post, we talk in detail about ISO and the concept of a shutter speed and aperture. Read about exposure triangle.
Today’s assignment is really simple. The entire assignment should take you less than 10 mins. For this assignment your goal is to learn how the three elements impact a photograph. Read the assignment before picking up the camera.
In this assignment, you will pick a subject and then take multiple photos by changing one element at a time. For detailed instructions, read the steps below completely before starting.
Step 1. Pick a Subject
Pick any subject. Pick a fruit or pick a veggie. Don’t slow down because you don’t have cooked food. Read previously posted tips on practicing food photography without cooking.
Step 2. Pick Your Triangle
Pick an ISO speed (if you don’t know where to start, pick ISO 400), shutter speed (start with 125 here) and aperture. Take a photograph with proper focus. This settings are your starting point.
Your first photo will have these settings 400-125-8 (ISO-Shutter Speed-Aperture)
Side Tip: If you are using autofocus and camera doesn’t seem to seem to do anything, this is usually because camera cannot “see” what to focus on. In that case increase the light, if you can.
Step 3. Now Change Aperture by 1 full-stop
Take another photo by increasing the aperture by 1 full-stop. If you started at f/8, increase aperture to f/11 and take a photo. Now reduce the aperture two stops and take a photo. Now you are at f/11 in our example, so change aperture to f/5.6.
Please use the following standard full-stop aperture for best:
In our example, you should have capture two photos with following settings:
400-125-11 and 400-125-8
Before going to next step, change your aperture stop to where you started (f/8 in our example).
Step 4. Next Change Shutter Speed by 1 stop
Similar to step 3, reduce shutter speed by one stop (from 1/125 to 1/60) and take a photo. Now increase shutter speed by two stops (from 1/60 to 1/250) and take a photo.
As above use only the following standard shutter speed
1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1
In this step, you should have captured two photos at these settings:
400-60-8 and 400-250-8
Bring the shutter speed back to the starting point.
Step 5. Now its ISO
Assuming you started at 400, increase ISO to the next level (800 in this case) and take a photo. Now decrease the ISO by two levels (200 in our example) and take a photo.
In this step again, you will have captured two photos. Settings should be as below:
800-125-8 and 200-125-8
Step 6. Analysis
At this step, download these photos to your computer. And analyze how exposure of each photo is affected by changing the three elements.
Interact with fellow Food Photographers
This 31-day series will be most fruitful if you share what you have learned and ask questions and answer questions from fellow readers. Have you introduced yourself yet? Go here and tell us about yourself, your blog, your twitter profile and all that. Interact with other food photographers and read about them.
Exposure Triangle by RobMan170