C-mount vs CS-mount lenses for machine vision

C-mount and CS-mount are two common lens mounts used in machine vision. They're similar in many ways, but there are important differences to consider when choosing the right one for your machine vision setup.

The main difference between C-mount and CS-mount is the flange focal distance (FFD), which is the distance between the lens mounting surface and the image sensor. C-mount has an FFD of 17.526 mm, while CS-mount has a shorter FFD of 12.5 mm.

Because of this difference, you can't directly attach C-mount lenses to a CS-mount camera. However, you can use C-mount lenses on a CS-mount camera by using a 5mm adapter ring. The shorter FFD of CS-mount lenses makes them incompatible with C-mount cameras.

Explore our broad online portfolio of industrial C-mount lenses.

C-mount lenses

In terms of compatibility, the C-mount standard is more widely used, offering a broader selection of lenses from various makers. C-mount lenses are versatile, working with both C-mount and CS-mount cameras.

However, CS-mount lenses are often cheaper as they use fewer glass elements. Both types support a maximum sensor size of 1.1", so they're not suitable for larger sensors found in high resolution cameras, which may require a different lens mount, such as the F-mount.

Advantages of C-mount lens

Versatility: C-mount lenses work with a wide range of image sensors, making them compatible with various machine vision cameras.

Manual Control: Allows precise adjustment of aperture (iris) and focus, ensuring control over image quality.

Secure Mounting: Strong and stable attachment between the lens and camera is ensured by the screw-threaded connection, ideal for applications requiring stability.

Durability: Designed for industrial environments, C-mount lenses can withstand tough conditions like vibrations and temperature extremes.

Disadvantages of C-mount lens

While C-mount lenses offer many benefits, there are a few drawbacks to consider:

• Size: Compared to some newer lens mounts, C-mount lenses can be physically larger. This might limit their use in applications where you need a compact setup.
• Cost: C-mount lenses can be more expensive than some alternative lens options for industrial vision cameras. This may be a factor depending on your budget and project requirements.

CS-mount lenses

The shorter FFD of the CS-mount allows for more compact camera designs, as the lens can be positioned closer to the sensor.

This makes CS-mount lenses well-suited for embedded vision applications where space is limited, such as in surveillance cameras and some machine vision systems.

The reduced FFD also enables the design of simpler and less expensive short-focus lenses.

Advantages of CS-mount lens

• Cost-effective: CS-mount lenses are generally a more affordable option compared to C-mount lenses. This can be a major advantage for projects with limited budget.
• Manual Focus: Like C-mount lenses, you can manually adjust the focus for precise image capture.
• Limited Aperture Control: In most cases, CS-mount lenses don't offer iris (aperture) adjustment. This might be a limitation if you need to control the depth of field in your application.
• Easy Mounting: The CS-mount design ensures a secure and straightforward lens attachment to the camera.

Disadvantages of CS-mount lens

• Availability: New CS-mount lens models are regularly introduced, ensuring access to the latest technology. However, older models may be discontinued (reach EOL - End-of-Life) unless very large orders (2000-5000 units) are placed. This is something to consider if long-term availability of a specific lens is crucial for your project.

Because of the unpredictable delivery reliability of CS-mount lenses, we do not carry this standard in our online store. However, we do provide them for volume projects starting from 100 pieces per year. Typically, the prices for these lenses range between 8 and 25 euros per unit. Moreover, we offer customization options for the iris. If you're interested in acquiring these lenses, please inform us.

C-mount and CS-mount lenses adaptability

While both C-mount and CS-mount lenses are common in machine vision, their compatibility with cameras differs:

Using C-mount lenses on CS-mount cameras:

You can attach a C-mount lens to a CS-mount camera by using a 5mm adapter ring. This ring fills the gap caused by the shorter flange distance in CS-mount cameras, ensuring proper focusing of the C-mount lens.

Using CS-mount lenses on C-mount cameras:

Unfortunately, directly mounting a CS-mount lens onto a C-mount camera is not feasible. The shorter design of the CS-mount lens prevents it from reaching the correct focal point due to the additional space in a C-mount camera.

How to choose between C-mount and CS-mount?

When choosing between C-mount and CS-mount for a machine vision application, the key considerations are the available space, the required lens characteristics, and the desired cost-effectiveness. C-mount offers a wider selection of lenses and is more versatile, while CS-mount is better suited for compact designs and cost-sensitive applications.

In conclusion, when choosing between C-mount and CS-mount for a machine vision system, the key factors to consider are:

1. Flange focal distance and lens compatibility
2. Camera size and space constraints
3. Sensor size and resolution requirements
4. Lens features and image quality needs
5. Budget constraints

Support for C-mounts vs CS-mount lenses?

We have a large portfolio of machine vision lenses available online. Additionally, we offer some custom solutions for lenses, ensuring you find the best fit for your machine vision system. Explore our portfolio of machine vision cameras, where the standard mount is C-mount, but we also provide options to select CS-mount or S-mount(M12 mount) in some models.

Need more info or have some questions about C-mount of CS-mount lenses? Fill out the form below and our team will be happy to assist you.