How to Approximately Measure Lux by Eye
To measure lux accurately, you will need to use a light meter. However, there will be times when this isn't convenient. To avoid this problem, you will need to find a way of measuring lux by eye. It is possible to estimate the lux in a scene, although it's not possible to accurately determine exactly how much light intensity is in a video scene.
Learning how to approximate lux by eye is a useful skill to learn. If you can master this, then you should be able to guess the settings required. It will also be possible to tell when your light meter is broken or not pointing at the right subject.Step 1: Understanding Lux
Before you can hope to estimate lux by eye, you will need to understand exactly what it is. Lux is a measure of light intensity and can be used to correctly set up your camera. A light meter can be aimed at a subject, and this will calculate the level of lux on the scene. The shutter speed and aperture settings can then be used to make sure your video camera records perfect videos.
Better lux meters are also capable of measuring a number of spots in a scene and averaging them out. This will make it possible to ensure that you are taking videos that are correctly exposed and will not cause any problems.Step 2: Preparing Yourself
The human eye is designed to detect changes in light and brightness. This is how we all see by capturing light which bounces off objects. While you will be able to tell the difference between dark and light, actually putting a lux value on it will be difficult. You will also only be able to make comparisons to things that you know.
Start trying to train yourself to tell the difference between different darkness in the same scene. You might also like to try to guess what your light meter is going to say.Step 3: Calibrating Your Eye
By now, you should be able to tell when something is darker than something else. However, you won't be aware of the lux value or the settings which should be used with your video camera. To get used to this, you have two options. You can either experiment with trial and error until you know, or you can use a light meter to train you.
With a light meter, you will be able to train yourself to estimate the lux. The light meter can be used in different scenes and you can try and guess what it will say. Over time, you will learn to make comparisons and it should be possible to start guessing the values of lux.Step 4: Practice
Measuring lux approximately with your eye is difficult. With practice, it is something that should get much easier. It should eventually become second nature which will make it possible to quickly and easily measure the lux without needing a lux meter. This is how photographers set their cameras in the days before lux meters.