I have a simple question (newbie). I hope someone can share the knowledge with me. I have this Tamron lens stated 5-50 mm with:
Manual Iris: F 1.4-Close Auto Iris: F 1.4-360
What does it means?
I know that 5-50 mm refers to the Focal Length.
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Sign up to join this communityI have a simple question (newbie). I hope someone can share the knowledge with me. I have this Tamron lens stated 5-50 mm with:
Manual Iris: F 1.4-Close Auto Iris: F 1.4-360
What does it means?
I know that 5-50 mm refers to the Focal Length.
You have a CCTV lens made by Tamron, possibly the 5-50mm here: http://www.tamron.co.jp/en/data/cctv/13vg550as2.html
The aperture values are read in the same way as on photographic lenses. In this case, your lens has a maximum aperture of f/1.4 to f/360. f/360 or even smaller apertures are necessary for CCTV cameras which may have extremely sensitive CCDs.
Auto iris lenses automatically stop the lens down or open it up when needed for outdoor CCTV applications; manual iris lenses are adjusted manually and used for indoor CCTV.
Aperture is the size of the opening through which light is allowed to pass. The smaller the number, the larger the opening and the narrower the depth of field and the more light gets in. The larger the number, the smaller the opening, the less light gets in and the bigger the depth of field. (Depth of field is the amount of distance which appears in focus.)