Industrial cameras typically do not come with lenses included. Therefore, once you’ve chosen your camera, you’ll need to select a lens. However, choosing a lens requires some knowledge. Even when looking at the specifications of lenses, it’s often difficult to determine which one is best.

The most crucial parameter in selecting a lens is the area you want to capture with the camera and the distance to the subject. For example, if you want to capture a 30cm by 30cm area and the camera will be positioned 1 meter away, having such preferences can simplify the lens selection process.

If you have preferences like the example above, consulting our lens selection experts will allow us to recommend the best lens for your needs. However, if you prefer to choose a lens yourself, you can do so using the following methods.

If you want to calculate and choose a lens yourself:

For fixed-focus lenses, you can calculate the area based on the lens’s f-value. Consider your desired area in the aspect ratio of the camera sensor. If the camera sensor has a 4:3 aspect ratio, then the field of view will also be in a 4:3 ratio.

For example, if you want to capture a 30cm by 40cm area:
40cm (horizontal) × 30cm (vertical) field of view.

The formula for calculating the f-value is:

f-value = (Distance to the object (mm) × Camera sensor size (horizontal or vertical in mm)) / Desired area (horizontal or vertical in mm)

You can use either the horizontal or vertical values for calculation. If you choose to use the vertical sensor size in the calculation, adjust the area to match the vertical dimension as well.

Calculating in the vertical direction:

f-value = (1000 × 4.8) / 300

This results in an f-value of 16mm.

If the calculated result is not available in the lens lineup (e.g., f-value = 20), choose the closest available lens. For example, if the closest options are 16mm and 25mm, selecting the 16mm lens will provide a wider field of view than your desired area, while the 25mm lens will provide a narrower field of view.

For more detailed information, please refer to the following link.

 

カメラのイメージサイズ

Actually, we have a convenient calculator on our company’s website that automatically calculates it for you by just entering the conditions. Simply select your camera and input the distance, and the optimal lens will be calculated for you. You can find the calculator at the following link

 

CCTVレンズ計算機

By leveraging ① and ②, you can select the lens you desire at any time.

Of course, you can always feel free to consult with our lens selection experts if you prefer.