# Know Anything About c-mount lenses? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [March 15, 2004, 3:55am UTC](https://boards.straightdope.com/t/know-anything-about-c-mount-lenses/234369 "2004-03-15T03:55:23Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![DougC](https://avatars.discourse-cdn.com/v4/letter/d/7feea3/32.png) [@DougC](https://boards.straightdope.com/u/DougC)\ **Post date:** [March 15, 2004, 3:55am UTC](https://boards.straightdope.com/t/know-anything-about-c-mount-lenses/234369/1 "2004-03-15T03:55:23Z")
- - - I have a night-vision scope that uses a c-mount lens. It is a head-mount unint that is 1X/no magnification, and I would like to get another lens that ideally is 3-5X, but I can’t find any lenses that are quite the same. The video security camera lenses I find all seem to use _very_ small-diameter lenses (6mm or so) where the existing lens uses optics that are about 20mm across. I notice that some lenses are sold for larger image areas (1/2" vs. 1/3"), would the lenses for larger areas be larger-diameter as well? - The only videocamera lenses I have found that use larger lenses are ones that include features like motorized focus, zoom and electronic irises–and I can’t use any of those things. The existing lens is just a threaded cell with a fixed focal length, that moves up and down in a collar, with the optics as large as possible. Where can I find anything like this? -And I guess I should point out, it’s gotta cost $50 or maybe $75 at most. ~ ---
**Author:** ![AncientHumanoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ancienthumanoid/32/278_2.png) [@AncientHumanoid](https://boards.straightdope.com/u/AncientHumanoid)\ **Post date:** [March 15, 2004, 4:43am UTC](https://boards.straightdope.com/t/know-anything-about-c-mount-lenses/234369/2 "2004-03-15T04:43:27Z")
[CCTV Lens Depot](http://www.cctv-lens.com/) [Where to find C-mount lenses](http://www.unibrain.com/download/pdfs/CMountManuf.pdf)