how come if you record a high quality video and take a frame out of it to use as photo it becomes low quality?

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how come if you record a high quality video and take a frame out of it to use as photo it becomes low quality?

In: Technology

5 Answers

Anonymous 0 Comments

There are essentially three factors working against you in this scenario. They are shutter speed, resolution and focus.

Shutter speed – depending on your frame rate, video looks good at about 1/50 second exposure, but stills are usually shot at 1/125 second and faster. This means that you will always have some motion blur in any image you capture from a video, making it less crisp. If you want to show an action moment in a still shot, you usually stage it as a frozen moment mid-action and shoot with a fast shutter to freeze it cleanly.

Resolution – you have to be shooting 8k video and better to be anywhere near the resolution of a typical stills camera. The lower resolutions afforded by 4k video and HD are always going to make any captured image look softer.

Focus – one of the magic things about the human eye is that movement wins in any battle for attention between a beautiful thing and a moving thing. In any video clip, the eye will follow whatever is moving, before it notices the bits of the frame that look beautiful. Watch this clip for evidence of this.

What this means is that you can get away with the moving thing in your frame not being precisely in focus. It’s extremely difficult to track focus on something that is moving, but a rough approximation is good enough to work while the image is moving. As soon as you freeze the image to make a still from it, you can see how out of focus it is.

The long and the short of it is that, if you want stills of your video, you’re always better off shooting proper stills with a proper stills camera. At a pinch, a frame grab from video can work, but you have to be really selective about choosing a pin sharp shot with as little movement as possible.

Anonymous 0 Comments

Video is captured at a constant rate. Meaning that the camera can’t change the amount of time each frame is exposed. This rate is chosen to keep the video moving smoothly but is usually suboptimal for a high quality image. Being unable to change exposure time means the camera has to change its aperture or gain to correct exposure. Most non professional cameras don’t have very good apertures, which leaves gain as a primary exposure control. Increasing gain is the lowest quality method of exposure compensation. On top of that, the exposure time in video allows formore motion blur than higher speed exposures which makes the image look slightly blurry compared to a fast exposure with good lighting.

Tldr; a fixed exposure speed is not an ideal method for image capture.

Anonymous 0 Comments

Because when you watch it with the other photos closely next to eachother it blends in with the other photos but a single picture is in movement and looks blurry.

Anonymous 0 Comments

What software are you using? I use Wondershare Filmora and the screen captures are as high quality as the video. You’ll still get motion blur as others have said, but if the person or object in the video is still, then that won’t be an issue and the images are high quality.

[Here’s](https://imgur.com/a/7q3XRNI) a random capture I just did from a 1080p version of the movie 300.

Anonymous 0 Comments

As others have to said, it could be due to the video capture itself.

Or it could be an optimization to make the thumbnail (the small picture it uses as a “preview”) load faster. Images, especially high quality ones, are very difficult for the CPU to process.