Security Camera Digital Zoom vs Optical Zoom
Watch this video to compare digital zoom vs optical zoom functions using a 4K fixed lens security camera and a 4mp pan tilt zoom camera (PTZ).
What is digital zoom?
Digital zoom uses a fixed lens security camera and magnifies the pixels in a certain area of image (the zoom area) and crops out the rest of the image that is outside of the zoom area. When digital zooming in, images and videos tends to get blurry as you zoom in more. This is because you are stretching the size of the pixels larger and larger, which essentially lowers the resolution.
What is optical zoom?
Optical zoom, also known as mechanical zoom, requires a security camera with a mechanical zoom lens, such as in a pan tilt zoom camera. The focal width of the lens physically expands and contracts as you zoom in and out of the image. There is no loss in resolution when you zoom in using optical zoom.
4K Dome IP Camera
This is the 4K dome IP camera with a fixed 3.6mm lens that was used in the video for the digital zoom demo.
4mp IP PTZ Camera
This is the 4mp IP PTZ camera with a 25x zoom lens that was used in the video to demonstrate optical zoom. The IP-PTZ-425 is an auto-tracking pan tilt zoom camera with AI software built-in. You can watch more PTZ demo videos of it here, including the auto-tracking AI function.
Viewtron IP Camera NVR
To make this video, both of the above cameras were connected to the Viewtron IP camera NVR at CCTV Camera Pros office. The digital zoom and optical zoom functions were both performed on the NVR.
Video Transcription
Digital zoom versus optical zoom. Good morning, everyone. Mike from CCTV Camera Pros here. In this video, I’m going to demonstrate and talk about the differences between a security camera that’s using a digital zoom versus one that’s using an optical or mechanical zoom.
So for the digital zoom, I’m going to use that 4K resolution fixed lens dome camera that you see behind me, the one on the left. And to demonstrate optical zoom or mechanical zoom, I’m going to use that pan tilt zoom camera that you see behind me. Let’s take a look at the demos and then we’ll talk more about exactly what the difference is afterwards.
So first up, I’m going to show you the digital zoom using that fixed lens dome camera. So, on the DVR that this camera is connected to, I’m going to select this zoom level. And I can drag this rectangle around to where I want to zoom in and then use this magnifying glass to zoom in on an area. Now you’ll notice the more that I zoom in, the more blurry the image gets. That’s because we’re not really zooming in using the lens of the camera, we’re just stretching the pixels in that particular area where that aqua rectangle is around and cropping out the rest of the image. It’s not a true zoom, it’s just stretching the image out. So I’m going to zoom back out and go back to the full size view, which is clear again.
Next up is the optical zoom using that pan tilt zoom camera. And optical zoom is also known as mechanical zoom because the focal length of the camera is actually widening and narrowing as you zoom in and out. And I’m going to pause here for a second. That silver SUV is 225 feet away from where the camera is installed. And you could see the image is crystal clear. When I resume the video, you’ll see me walk into the view here. And I just wanted to show you what a person looks like at 225 feet away with the optical zoom. So you could see, I mean, you can make out my face, you can make out I’m obviously a person, and just crystal clear with the optical zoom.
So I want to summarize, again, the difference between digital zoom versus optical zoom. Digital zoom uses a fixed lens camera and generally the recorder, the DVR or NVR that the security camera is connected to, is magnifying pixels in a certain area of image and then cropping out the rest of the image that’s not magnified. And the more you digitally zoom in, the more blurry the image gets because the pixels are getting bigger and bigger, which essentially you’re losing resolution.
Optical zoom, on the other hand, also known as mechanical zoom, that’s when you have a zoom lens, a mechanical zoom lens, such as in a pan tilt zoom camera and the focal width of the lens is actually changing as you zoom in and out of the image. And I used a 25 time zoom camera. And as you saw, that vehicle that was 225 feet away is still crystal clear when I zoom into it because the lens is mechanically adjusting. The pixel actually stays the same. And actually, the pan tilt zoom camera that I was using is four megapixel resolution. And the fixed dome camera is 4K resolution. So the fixed dome is twice the resolution of the pan tilt zoom. But you could see, when it comes to zooming in, the mechanical zoom way outperforms digital zoom for obvious reasons.
If you have any questions of out any of this, feel free to reach out to me anytime. I can be reached at mike@cctvcamerapros.net. If you want to learn more about these Viewtron security camera systems that I used to make these videos, we have BNC security cameras, IP cameras, AI security cameras, license plate recognition systems, all kinds of accessories, everything for home, business and government. You can learn about all of it at www.cctvcamerapros.com/viewtron. Thank you for watching.
