What is the difference between PTZ and ePTZ video cameras?

With the widespread application of live video and video conferencing, we come into contact with a variety of different video equipment, including PTZ cameras and ePTZ cameras. Many people don't know the specific differences. So what are the differences between a PTZ video camera and an ePTZ video camera? 

Let's first understand what PTZ  and ePTZ are.

What is PTZ?

PTZ is the abbreviation of "pan-tilt-zoom". A PTZ video camera physically moves the camera through the built-in motor, so that it can rotate horizontally and vertically. This will also adjust the aim and zoom of the camera. You can understand in this way that the traditional PTZ camera is a camera that is controlled remotely. The user uses the remote controller or PTZ application to pan (move the camera left and right), tilt (rotate the camera up or down), or zoom (zoom in or zoom out the video). 

What is ePTZ?

ePTZ video camera is short for  "electronic pan-tilt-zoom" or called digital PTZ. Technically speaking, ePTZ refers to software functions rather than hardware. The ePTZ camera cannot be moved physically, although it works well to tilt, pan or zoom.  The operation does not involve the movement of any mechanical parts. ePTZ just takes an image in the camera frame and moves within it. This function is similar to zooming in and moving an image when taking a photo on a smartphone. Therefore, the ePTZ camera keeps still and completes the operation of tilt, pan, or zoom through the digital simulation inside the high-resolution senso. The digital zoom technology is used to achieve these operations with an ePTZ video camera.

What is the difference between PTZ and ePTZ cameras?

Zoom

The ePTZ video camera device is supported by digital zoom, which reduces the resolution while increasing the pixels. When you zoom in an ePTZ camera, you are actually "stretching" the original image. If you zoom in 4 times, the image resolution will be reduced by 4 times. Likewise, after magnifying the 5-megapixel image by 2 times, you will get a 2.5-megapixel image. In general, the more the ePTZ camera enlarges the image, the more the resolution will drop.

On the other hand, a PTZ video camera is equipped with optical zoom, and the image quality will not be affected by zoom. For example, if you zoom a 1-megapixel PTZ camera to the farthest point, the image you get is still 1-megapixel. So PTZ video cameras can zoom in the image without losing any resolution quality even when it is fully zoomed.

Range of view

The field of view of the ePTZ video camera is limited by the field of view of the fixed lens. Generally, the horizontal view is only between 70-130 degrees.

The PTZ camera has a wider field of view because of its own electric component structure, which can cover a larger area. Many PTZ cameras can pan 340 degrees horizontally and tilt 120 degrees vertically, so users can aim the real-time PTZ video camera at any area at any time.

Size and cost

The structure of the ePTZ camera is very simple: a lens and a sensor, therefore the price is cheaper in general. Without complex components, a smaller ePTZ camera will cost less.

On the contrary, a PTZ camera contains a motor for pan-tilt-zoom function, components for adjusting the lens and camera positioning, and other advanced firmware. Therefore, the structure of the PTZ camera is more complicated, the installation and deployment are more complicated, and the corresponding price will be higher compared to ePTZ cameras. 

Advantages and disadvantages of ePTZ and PTZ cameras

The two major disadvantages of the ePTZ video camera are the image resolution and field of view. Video cameras with ePTZ will lose resolution due to zooming in, hence, those that are on the market are equipped with very high resolution, such as 4k resolution. For example, Nexvoo's CC520 is equipped with a 5x 4K UHD 2160p ePTZ camera. After magnifying the image 5 times, it can still achieve a 720p image effect even if the resolution is reduced by 5 times. While the PTZ camera using optical zoom does not need to be worried about this problem, the 4K PTZ camera still has a 4K resolution even after magnifying the image 30 times.

The ePTZ video camera is restricted by the field of view of a fixed lens. Its field of view is much narrower than that of the PTZ video camera, which can be translated up to 340 degrees and tilted up to 120 degrees.  Therefore, many ePTZ video cameras on the market are broadening the horizontal viewing angle in order to make up for this disadvantage.

There are three main advantages of ePTZ cameras: small size, low price, and automation. Since there is no need for mechanical pan, tilt, and zoom, the structure of an ePTZ camera is much simpler than that of a PTZ camera. The size will be smaller, and the use will be easier. Lastly, ePTZ cameras are suitable for installation in areas where PTZ cameras cannot be installed.

The high costs of the PTZ video camera are mainly due to the many motors and other components involved in lens adjustment and camera positioning.  The ePTZ cameras don't have these mechanical components, therefore, they cost significantly lower than PTZ video cameras.

The ePTZ camera also has the ability to move to a new lens immediately, which is an intelligent function of automation. For example, Nexvoo's CC520 has an automatic viewfinder function. If you use a PTZ camera, you have to wait for the mechanical motor to move to the new P, T, and Z positions.

Final words

ePTZ video cameras and PTZ video cameras have their pros and cons, and both are excellent solutions for live broadcast and video conferencing.  Depending on your needs and situation, it's up to you to decide which camera is best. If you are a teacher and want to create a great distance learning experience for your students, then a simple ePTZ camera is all you need, like that of Nexvoo ClassCam CC520. If you want to zoom in close without losing image quality or need a wider field of view, then you need a PTZ video camera, such as AVer's PTZ330 and Logitech's PTZ PRO 2.