I thought that "PL" stood for "polarizing lens." Dan Matyola http://www.pentaxphotogallery.com/danieljmatyola
On Thu, Jul 23, 2015 at 10:32 AM, Igor PDML-StR <pdml...@komkon.org> wrote: > > > Hi Darren, > > So, the initial "PL" was for PoLarizer (as Bill suggested)? > That's weird! But those things happen... > > I am recalling that when I saw "PL" many years ago, I actually thought it > could've been for "Linear Polarizer" but possibly in a different language > (e.g. French), where the word sequence is reverse (polarisant lin'eaire). > > > As for varios markings for Cirular Polarizers, I found that at least two > companies/brands also used "PLD" (Quantaray) or "P.L.D." (Marumi): > http://www.bhphotovideo.com/c/product/800690332-USE/ > Any idea what that "D" stands for? And why it is writed with the periods > (dots?) as an initialism? > http://www.marumi-filter.co.jp/en/product/02/dhg_s_cpld.php > (You can see it engraved on the filter.) > > In the letter case, it is funny that they write "Circular PL" on the > website. > > > Now, my 3 guesses that I mentioned yesterday but didn't write to avoid any > bias were: lens, light, and luminescence that would be in the scientific > term "circularly polarized luminescence". Obviously, none of these would be > correct in "CPL filter". > > Igor > > > > Darren Addy Thu, 23 Jul 2015 04:44:15 -0700 wrote: > > It isn't an acronym. PL was originally the abbreviation printed on > linear polarizers from almost all manufacturers. When circular > polarizers came into being (and were necessary to avoid exposure and > focus problems with modern cameras that use semi-silvered mirrors or > prisms to split the light entering the viewfinder in order to > calculate exposure and focusing distance) they had to be > differentiated in some way. You will see them called CPL, PL-CIR, and > PL-C (perhaps others) by various manufacturers. > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
