Canon L lens - wikipedia Canon L lens This article contains weasel words : vague phrasing that often accompanies biased or unverifiable information. Such statements should be clarified or removed. ( March 2009 ) The 70 - 200 mm f / 2.8 L lens Canon 's series of L lenses ( Canon Luxury Lenses ) are a professional line of SLR photography lenses made by Canon. Canon has sold zoom and prime L - series lenses for the discontinued FD lens mount and for the current EF lens mount used on all Canon EOS cameras. Contents 1 Characteristics 2 Lenses 2.1 EF mount zoom lenses 2.2 EF mount prime lenses 3 Canon lens codes 4 See also 5 References 6 External links Characteristics Most L series lenses share a number of common characteristics not found in Canon 's line of lower - end lenses. L lenses tend to be more durable, incorporating dust and water - resistant rubber seals on some models. L lenses also contain optics of higher quality, with many lenses containing aspherically ground, fluorite or ultra-low dispersion glass elements. Their front elements do not rotate for the proper operation of some filters, such as circular polarizers. L lenses are often `` fast '', with maximum apertures commonly f / 2.8 or f / 4 and never exceeding f / 5.6. Standard prime lenses have a much higher maximum aperture, with both of Canon 's current 50mm and 85mm L lenses which open to f / 1.2. All current L - series lenses have ultrasonic autofocus motors ( USM ) and extra communication pins, except for the specialist tilt - shift lenses which do not provide autofocus. A gelatin filter holder, on the rear of an EF lens. Larger sized L - lenses, such as the 70 -- 200 mm, 100 -- 400 mm zooms, and longer focal length primes ( 300 mm+ ), usually have an off - white barrel to reduce heat absorption under the sun that may otherwise affect the performance of the lens, as well as to identify Canon 's lenses ( for example at sporting events ), though these can be confused with Sony A and Pentax K - mount lenses which are also offered in ( pure ) white. However, shorter focal length L - lenses can be black ( such as the Canon EF 24 -- 70 mm f / 2.8 L ) and all L - lens primes under 200 mm are black. L - lenses can be identified by the distinctive red ring on the lens barrel. The off - white colour of the lens barrel is not exclusive to L lenses, since the Canon 400mm f / 4 DO non-L lens is off - white with a green ring. Wide angle L - lenses typically have a gelatin filter holder on the mounting point of the lens, which allows the photographer to cut a small, square piece of gelatin out of a larger filter sheet and place it on the lens. On film cameras, these are typically used to correct the color temperature, but on digital cameras this is largely unnecessary, as the color temperature can be corrected in software. The mount is still commonly used for neutral density gelatin sheets though, especially on certain wide - angle lenses where the protruding front element precludes the use of any screw - in filters. Some telephoto L - lenses, such as the EF 70 - 200mm zoom lenses, or the EF 300mm f / 4L IS USM do not have rear gelatin filter holders. Super-telephoto lenses such as the EF 500mm f / 4L IS USM, or the EF 200mm f / 2L IS USM have a rear 52mm drop - in filter holder which can be used to hold gelatin type filters. Lenses EF mount zoom lenses Name Category Min focal length mm Max focal length mm Max aperture at min focal length f / Max aperture at max focal length f / USM IS Current product 8 - 15mm f / 4L USM fisheye Wide - angle 8 15 11 - 24mm f / 4L USM Wide - angle 11 24 16 - 35mm f / 2.8 L USM Wide - angle 16 35 2.8 2.8 16 - 35mm f / 2.8 L II USM Wide - angle 16 35 2.8 2.8 16 - 35mm f / 2.8 L III USM Wide - angle 16 35 2.8 2.8 16 - 35mm f / 4L IS USM Wide - angle 16 35 17 - 35mm f / 2.8 L USM Wide - angle 17 35 2.8 2.8 17 - 40mm f / 4.0 L USM Wide - angle 17 40 20 - 35mm f / 2.8 L Wide - angle 20 35 2.8 2.8 24 - 70mm f / 2.8 L USM Standard 24 70 2.8 2.8 24 - 70mm f / 2.8 L II USM Standard 24 70 2.8 2.8 24 - 70mm f / 4L IS USM Standard 24 70 24 - 105mm f / 4L IS USM Standard 24 105 24 - 105mm f / 4L IS II USM Standard 24 105 28 - 70mm f / 2.8 L USM Standard 28 70 2.8 2.8 28 - 80mm f / 2.8 - 4.0 L USM Standard 28 80 2.8 28 - 300mm f / 3.5 - 5.6 L IS USM Telephoto 28 300 3.5 5.6 35 - 350mm f / 3.5 - 5.6 L USM Telephoto 35 350 3.5 5.6 50 - 200mm f / 3.5 - 4.5 L Telephoto 50 200 3.5 4.5 70 - 200mm f / 4.0 L USM Telephoto 70 200 70 - 200mm f / 4.0 L IS USM Telephoto 70 200 70 - 200mm f / 2.8 L USM Telephoto 70 200 2.8 2.8 70 - 200mm f / 2.8 L IS USM Telephoto 70 200 2.8 2.8 70 - 200mm f / 2.8 L IS II USM Telephoto 70 200 2.8 2.8 70 - 300mm f / 4 - 5.6 L IS USM Telephoto 70 300 5.6 80 - 200mm f / 2.8 L Telephoto 80 200 2.8 2.8 100 - 300mm f / 5.6 L Telephoto 100 300 5.6 5.6 100 - 400mm f / 4.5 - 5.6 L IS USM Telephoto 100 400 4.5 5.6 100 - 400mm f / 4.5 - 5.6 L IS II USM Telephoto 100 400 4.5 5.6 200 - 400mm f / 4L IS USM 1.4 x Extender Telephoto 200 400 EF mount prime lenses Name Category Focal length mm Max aperture f / USM IS Current product 14mm f / 2.8 L USM Wide - angle 14 2.8 14mm f / 2.8 L II USM Wide - angle 14 2.8 24mm f / 1.4 L USM Wide - angle 24 1.4 24mm f / 1.4 L II USM Wide - angle 24 1.4 35mm f / 1.4 L USM Wide - angle 35 1.4 35mm f / 1.4 L II USM Wide - angle 35 1.4 50mm f / 1.0 L USM Standard 50 50mm f / 1.2 L USM Standard 50 1.2 85mm f / 1.2 L USM Medium telephoto 85 1.2 85mm f / 1.2 L II USM Medium telephoto 85 1.2 85mm f / 1.4 L IS USM Medium telephoto 85 1.4 135mm f / 2.0 L USM Telephoto 135 200mm f / 1.8 L USM Telephoto 200 1.8 200mm f / 2.0 L IS USM Telephoto 200 200mm f / 2.8 L USM Telephoto 200 2.8 200mm f / 2.8 L II USM Telephoto 200 2.8 300mm f / 2.8 L USM Telephoto 300 2.8 300mm f / 2.8 L IS USM Telephoto 300 2.8 300mm f / 2.8 L IS II USM Telephoto 300 2.8 300mm f / 4.0 L USM Telephoto 300 300mm f / 4.0 L IS USM Telephoto 300 400mm f / 2.8 L USM Super-telephoto 400 2.8 400mm f / 2.8 L II USM Super-telephoto 400 2.8 400mm f / 2.8 L IS USM Super-telephoto 400 2.8 400mm f / 2.8 L IS II USM Super-telephoto 400 2.8 400mm f / 5.6 L USM Super-telephoto 400 5.6 500mm f / 4.5 L USM Super-telephoto 500 4.5 500mm f / 4.0 L IS USM Super-telephoto 500 500mm f / 4.0 L IS II USM Super-telephoto 500 600mm f / 4.0 L USM Super-telephoto 600 600mm f / 4.0 L IS USM Super-telephoto 600 600mm f / 4.0 L IS II USM Super-telephoto 600 800mm f / 5.6 L IS USM Super-telephoto 800 5.6 1200mm f / 5.6 L USM Super-telephoto 1200 5.6 100mm f / 2.8 L Macro IS USM Macro 100 2.8 180mm f / 3.5 L Macro USM Macro 180 3.5 17mm f / 4.0 L Tilt - Shift Tilt - shift 17 24mm f / 3.5 L Tilt - Shift Tilt - shift 24 3.5 24mm f / 3.5 L II Tilt - Shift Tilt - shift 24 3.5 50mm f / 2.8 L MACRO Tilt - Shift Tilt - shift 50 2.8 90mm f / 2.8 L MACRO Tilt - Shift Tilt - shift 90 2.8 135mm f / 4L MACRO Tilt - Shift Tilt - shift 135 Canon lens codes On the back of Canon lenses is a six - digit code, which indicates where the lens was manufactured and when. Example of a code `` UV1212 '' The first letter, ' U ', represents the factory that made the lens. Three possible first letters are : U = Utsunomiya = Fukushima O = Ōita The second letter, ' V ', represents the year of manufacture = 1960, 1986, 2012 = 1961, 1987, 2013 = 1962, 1988, 2014 = 1963, 1989, 2015 = 1964, 1990, 2016 = 1965, 1991, 2017 = 1966, 1992 = 1967, 1993 = 1968, 1994 = 1969, 1995 = 1970, 1996 = 1971, 1997 = 1972, 1998 = 1973, 1999 O = 1974, 2000 = 1975, 2001 Q = 1976, 2002 = 1977, 2003 = 1978, 2004 = 1979, 2005 U = 1980, 2006 V = 1981, 2007 = 1982, 2008 X = 1983, 2009 Y = 1984, 2010 Z = 1985, 2011 The next two digits represent the month of the lens is manufactured. The last two digits are for internal Canon use. Therefore, the example ( pictured ) of UV0512 means the lens was made in the Utsunomiya, Japan factory in May 2007. See also Canon EF lens mount References Jump up ^ Canon Europa N.V. and Canon Europe Ltd 2002 - 2015. `` Black or White Lenses - Canon Professional Network ''. Canon Professional Network. External links At the-digital-picture.com : Canon L Lens Series Information On Canon Website : EF LENS WORK III Canon Subsidiaries Océ Products Cameras Canon 7 Canon AF35M Canon Cinema EOS Canon ELPH Canon EOS Canon FL Canon Canonflex Canon II Canon PowerShot Canon T series Canonet Canon P Lenses Canon EF lens mount Canon EF - S lens mount Canon FD lens mount Canon FL lens mount Canon L lens Canon EF - M lens mount Other Camcorders Canon Cat Canon V - 20 Canon EOS flash system Wordtank Technologies DIGIC Digital Photo Professional Ultra Fast Rendering People Fujio Mitarai Other Canon K.K. v Green Cartridge Co. Canon Eagles Canon Open Category Commons Retrieved from `` https://en.wikipedia.org/w/index.php?title=Canon_L_lens&oldid=804800361 '' Categories : Canon L - Series lenses Hidden categories : Articles with weasel words from March 2009 Talk Contents About Wikipedia Español Français 한국어 Nederlands Tiếng Việt 中文 Edit links This page was last edited on 11 October 2017, at 07 : 05. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: what do the colored rings on canon lenses mean
Answer: to reduce heat absorption under the sun that may otherwise affect the performance of the lens