Archived posting to the Leica Users Group, 2007/05/08
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Claudio, Originally when Leica announced the 6 bit coding it was to identify the lens and optimize it's performance. Probably to correct for vignetting. Then it was discovered that the Leica image sensor had a reduced infra red filter which caused certain dark materials like polyester cloth, leather and even natural colors of flowers to turn toward a strong magenta color. In order to eliminate the magenta caused by the strong IR, Leica suggested using a special IR/UV filter to remove the IR and correct the off color cast. This is fine but the filter causes the edges and the corners of the photo to turn a cyan color. This problem is increased as the angle of the light increases through the filter. The widest angle lenses are the worst and the condition improves as the angle decreases in the lesser angled lenses. Leica found they could correct for this cyan color cast by compensating the color of the affected edges of the photo. Since the amount of compensation is different for the different lenses, the camera has to know what lens is being used when the special filter is installed. The way to do this is to code the lenses. Regards, Len On May 8, 2007, at 9:12 AM, Dott. Ing. Claudio Rimediotti wrote: > Thanks! > And now another question: > the reason why of this 6-bit code? > > Thanks again, > > Claudio > > ----- Original Message ----- From: "Eric Korenman" <faneuil@gmail.com> > To: "Leica Users Group" <lug@leica-users.org> > Sent: Tuesday, May 08, 2007 12:47 PM > Subject: Re: [Leica] Lenses without 6 bit code in M8 > > >> short answer: none! >> >> Eric >> >> >> On 5/8/07, Dott. Ing. Claudio Rimediotti >> <studio.rimediotti@iol.it> wrote: >>> >>> I'd like to know what are the problem to use old Leica lens >>> without 6 bit >>> code in an M8. >>> >>> Thanks, regards from Italy! >>> >>> Claudio Rimediotti >>> >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >>> >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information