View source for Engineering:S-mount (CCTV lens)

{{Short description|Lens mount used in some CCTV cameras and webcams}}
[[File:Three M12 lenses for board or CCTV cameras.jpg|thumb|right|300px|Three S-mount lenses with different focal lengths (left to right: 16&nbsp;mm, 6&nbsp;mm and 8&nbsp;mm)]]

The '''S-mount''' is a standard lens mount used in various surveillance CCTV cameras and webcams. It uses a male metric M12 thread with 0.5&nbsp;mm pitch on the lens and a corresponding female thread on the lens mount. S-mount lenses are often called "M12 lenses". Because the lens mounts are usually attached directly to the [[Engineering:Printed circuit board|PCB]] of the sensor, they are often called "board lenses".<ref>{{Cite web |url=https://www.edmundoptics.eu/knowledge-center/application-notes/imaging/lens-mounts/ |title=Lens Mounts |date= |access-date=2022-07-12 |website=Edmund Optics |last=Firestone |first=Kyle}}</ref> The supported [[Engineering:Charge-coupled device#Sensor sizes|sensor format]]s range from smaller than 1/6-inch type up to 1-inch having an 16mm diagonal sensor. The lenses lack an [[Physics:Diaphragm (optics)|iris control]]. S-mount lenses do not have a flange and therefore there is no fixed lens to sensor distance and they must be adjusted to focus.<ref>{{Cite web|url=https://commonlands.com/pages/lens-mounts-101|title=CS-Mount vs C-Mount vs M12 Explained}}</ref> Due to the small size of the lens barrel, performance is somewhat limited compared to larger lenses<ref>{{Cite web |url=https://www.framos.com/en/articles/choosing-m12-lens-mounts-for-specific-applications |title=Choosing M12 Lens Mounts for Specific Applications |date=2018-02-16 |access-date=2022-07-12 |website=Framos}}</ref> and most S-mount lenses are relatively slow ({{f/}}1.6 and slower). High-end CCTV cameras generally use C/CS-mount lenses, where much faster apertures like {{f/}}1.0 are common.

==See also==
* C-mount
* [[Engineering:ISO metric screw thread|ISO metric screw thread]]
* List of lens mounts

==References==
{{reflist}}

[[Category:Webcams]]

{{Sourceattribution|S-mount (CCTV lens)}}