Traditional Culture Encyclopedia - Photography and portraiture - No kidding, I'll show you the histogram in a minute.

No kidding, I'll show you the histogram in a minute.

How to treat common histograms?

1. When shooting:

When using the camera back screen or electronic viewfinder, the histogram can be used to confirm whether the exposure parameters of the current picture are appropriate, and it can be displayed when taking pictures or videos.

2. Looking back:

After the shooting is completed, you can view more detailed histograms (such as RGB histograms that will be introduced later) when you play back the photos, so that you can have a more comprehensive understanding of the photos.

3. When retouching:

In the post-editing process, the histogram will always be displayed in the corner of the screen. The histogram will change in real time according to your adjustment operation and play an important reference role.

1. Camera Tone Range:

The horizontal axis represents the brightness value of 0-255, the leftmost value of 0 represents pure black, the rightmost value of 255 represents pure white, and the middle value represents gray levels with different brightness.

2. The hue range of the scene:

If the peak of the histogram is on the horizontal axis, all the details of the photo are recorded.

3. Shadow:

The left side of the horizontal axis (shaded area) represents the shaded part of the scene.

4. Intermediate sound:

If it is a gray scene, its histogram should be gathered in the middle of the horizontal axis.

5. Highlights:

The right side of the horizontal axis (highlight area) represents the highlight part in the scene.

6. Pixels:

The vertical axis in the quantity histogram represents the number of pixels, and the peaks at different positions represent the number of pixels corresponding to different brightness.

The curve transitions from dark to bright, and the gray details on the natural film are rich.

The curve is seriously Jerry Zuo film, dark or seriously underexposed.

The curve is seriously to the right, and the spilled film is too bright or seriously overexposed.

The curve is steep and concentrated in a narrow gray area with low contrast.

Judging the exposure—

Underexposure:

In this diagram, the peak value of the histogram is mainly concentrated in the middle and the shadow part on the left of the coordinate axis, and the information in the highlight part on the right is insufficient. In order to improve this situation, users can increase exposure compensation, increase aperture, reduce shutter speed and increase the value of S0 (there are more details on the page).

Overexposure:

When shooting a relatively dark object, the histogram should be on the left side of the coordinate axis, but the histogram of this photo is on the right side of the horizontal axis (highlight), indicating that the object was shot too brightly. Users can reduce the exposure by means of exposure compensation or adjusting the combination of exposure parameters to improve this situation.

Low contrast scene:

In a low contrast scene, the histogram is gathered at a certain position on the horizontal axis (this position is usually in the middle). If you shoot a file in RAW format instead of JPEG format, we suggest that you can "expose to the right" and then lower the brightness later to get better picture quality.

High contrast scene:

In high contrast scenes, histograms will be gathered at the left and right ends of the coordinate axis. This kind of high contrast scene is very common in landscape photography. If you need to reduce the contrast in the scene, you can fill the subject with a flash, or take multiple photos and then synthesize them later.

RGB histogram—

Histogram can not only check the brightness problem, but also let us see the intensity of different colors. Usually, the histogram we see is a "brightness histogram" that shows brightness, but there is actually another kind called "RGB histogram". This histogram can display the brightness information of red, green and blue color channels respectively. It is very useful for photographers to be able to view the brightness of different colors separately.

Because even the most "perfect" exposure, the brightness of one or several colors in the picture may be overexposed. In post-processing, this overexposed highlight color often causes unexpected loss of details. Generally speaking, the brightness histogram and the histogram of green pixels are basically the same, so you need to pay attention to the histogram of blue and red.