Most of the DJI products have the histogram in DJI GO application, but do we really need it? First of all we have to turn the histogram on: 1: Start the DJI Go APP 2: Enter the camera view
3 : Tap the Menu
4 : Select the Settings
5 : Histogram on
The histogram is a useful but often misunderstood tool that the DJI GO app provides to help you get the correct exposure on your images. In this article we’re going to look at how to read it and use it to your advantage to help you do just that. Getting the best exposure (there is not such thing as the “correct” exposure, as it’s all subjective) in camera should be your goal every time you click the shutter.Using these tips should help you increase your success rate with land and areal shots.
What is a histogram? Dictionary definition: A bargraph of a frequency distribution in which the widths of the bars are proportional to the classes into which the variable has been divided and the heights of the bars are proportional to the class frequencies. HUH?! Anyone else confused? But what does it do? How do you read it? Let’s have a look!
How to read the Histogram? A histogram is a graphical representation of the pixels exposed in your image. The left side of the graph represents the blacks or shadows, the right side represents the highlights or bright areas and the middle section is mid-tones (middle or18% grey). How high the peaks reach represents the number of pixels in that particular tone. Each tone from 0-255 (o being black and 255 beingwhite) is one pixel wide on the graph, so imagine the histogram as a bar graphall squished together with no spaces between each bar. Have a look at the diagrams below: What can we learn from this histogram? There are many things we can learn about an image just by looking at the histogram. We can tell an imageis well exposed if it reaches fully from edge to edge without a space on oneside of the graph, and isn’t heavily going up one side or the other. In an ideal world, it should just touch the left and right edges, and not spill up the sides, with a nice arch up in the center. However, that doesn’t always apply in every situation, for every scene. Here are a few examples: * This is a histogram for a light subject (light sky ) with mostly light tones in the scene and few dark areas. See how it is shifted to the right now versus the dark subject. This is correct.
*This is a histogram for a dark subject, it is not wrong it is just more shifted to the right to represent the tones of the subject. This might be a dark forest, shadows or the any other dark object
* This is how an ideal histogram might look, evenly distributed, edge to edge, not up the sides
When the histogram tells you to adjust your exposure? Gaps on either end indicate you are missing information and your exposure can be shifted safely without losing detail. When your graph is shifted too far in one direction or the other so that it does not even touch the other edge – that means you can safely shift your exposure to cover more of the range of tones. Let’s look! * Now we see a gap on theright side of the graph indicating there are no whites represented so the image will be dark, too dark. You can safely give the image more exposure until you see the graph just touch the right edge * This graph shows an overexposed image, notice the gap on the left side indicating a lack of any blacks represented. It also means you will lose lots of detail in the white areas that may not be recoverable. In this case shift to give your image less expo
Summary By using the histogram on your aircraft camera, it is easier to see how to adjust your image exposure. There is a lot more to know about the histogram, and you can use it when you process your images in Photoshop or Lightroom as well. Keep in mind that if you shoot JPG format, nailing the exposure in camerais even more critical. If you shoot RAW format you have some leeway to make adjustments later, but it’s still a better idea to get it right in the first place.
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