Archived posting to the Leica Users Group, 2018/04/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Yes, the filters reduce the amount of light hitting the individual sensors, thus the reduced sensitivity. Without the filters, more light reach the panchromatic sensors of the Monochrom cameras. On 3 April 2018 at 19:36, Howard L Ritter Jr <hlritter at twc.com> wrote: > Notwithstanding any other considerations that may have to do with Bayer or > other filter schemes, isn?t it still true that in any color sensor, because > each photosite has a monochromatic filter over it, that site will receive > only one-third (notionally) of the incident white light on it, and greater > proportions of any non-white mixture ? but in any case, lose anything from > just a bit to a whole lot of the incident light, and therefore have a lower > average ISO than an unfiltered monochrome sensor? > > ?howard > > > On Apr 2, 2018, at 19:05, Ken Iisaka <ken at iisaka.com> wrote: > > > > There are many freely available documents on what Bayer sensors are, for > > example: > > > > https://en.wikipedia.org/wiki/Bayer_filter > > > > "Demosaicing", in the simplest term, is an interpolation algorithm and > has > > very little to do with "anything blue in the image has to pass through a > > red then green grid layer first." > > > > Here's a description of Foveon sensors, which actually captures blue > light > > first, then green then red at last. > > > > https://en.wikipedia.org/wiki/Foveon_X3_sensor > > > > Because all three colors are captured at the same location, no > > "demosaicing" is necessary with Foveon sensors. In addition, no > > "demosaicing" is necessary with monochromatic, or rather, panchromatic > > sensors, as each pixels capture light from a wider range of wavelength, > not > > limited to one "color" > > > > All image sensors in use today have a grid layout. Foveon sensors have > > multiple layers to detect light of different wavelengths. Bayer sensors > use > > separate pixels to capture levels of different wavelengths. > > > > Here's more explanations about different filter array designs: > > > > https://en.wikipedia.org/wiki/Color_filter_array > > > > > > > > On 2 April 2018 at 15:32, Mark Rabiner <mark at rabinergroup.com> wrote: > > > >> If there are so many factual errors then why not show us one? Show us > how > >> the Bayer process really works! Otherwise this is just added to the > list of > >> crass personal attacks which have compiled over the years from you. And > >> let's see one of your pictures Ken! > >> > >> > >> > >> > >> -- > >> > >> Mark William Rabiner > >> Photographer > >> > >> ?On 4/2/18, 5:16 PM, "LUG on behalf of Ken Iisaka" <lug-bounces+mark= > >> rabinergroup.com at leica-users.org on behalf of ken at iisaka.com> > >> wrote: > >> > >> There are so many factual errors. What Mark describes is Sigma Foveon > >> sensors. It has nothing to do with Bayer-layout sensors used by Leica > >> and > >> most other cameras. > >> > >> Just go take pictures. > >> > >> On 1 April 2018 at 03:41, Mark Rabiner <mark at rabinergroup.com> > wrote: > >> > >>> It?s the same speed but it can skip having to pass though various > >> filters > >>> first in the RGB Bayer process. It's just direct. > >>> Makes for a far cleaner final result. > >>> As I understand it demosaicing means anything blue in the image has > >> to > >>> pass through a red then green grid layer first. > >>> Anything green has to pass though just the red gird layer one first. > >>> And if it?s a red rose its fairly direct. Should look good. > >>> A black and white sensor has none of that. No grids. No layers. > >> Everything > >>> direct. > >>> Its keeping it simple stupid. I like that. > >>> > >>> > >>> > >>> > >>> -- > >>> > >>> Mark William Rabiner > >>> Photographer > >>> > >>> ?On 3/31/18, 12:14 PM, "LUG on behalf of Paul Roark via LUG" > >>> <lug-bounces+mark=rabinergroup.com at leica-users.org on behalf of > >>> lug at leica-users.org> wrote: > >>> > >>> On Sat, Mar 31, 2018 at 7:59 AM, chris williams via LUG < > >>> lug at leica-users.org > >>>> wrote: > >>> > >>>> ?... > >>>> > >>>> > >>>> Leica was able to use some kind of sensor made in Belgium that > >> was > >>>> strictly designed for monochromatic images. > >>>> > >>>> ?... > >>> > >>> Yes, but aside from not having an R, G or B filter over the > >> pixel, the > >>> silicon is still the same speed as that under the filters of the > >> color > >>> sensors. The monochrome's native speed is higher only because > >> it has > >>> no > >>> color filters over the pixels. I don't think the Leica foundry > >> has > >>> found > >>> any breakthrough to increase silicon's native light sensitivity. > >>> > >>> I'm not knocking the monochrome at all. For street photography > >> or > >>> where > >>> you don't need a filter, it's truly faster and a great tool for > >> those > >>> types > >>> of photography. > >>> > >>> Paul > >>> www.PaulRoark.com > >>> > >>> > >>> ? > >>> > >>> _______________________________________________ > >>> 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 > >>> > >> > >> > >> > >> -- > >> Ken Iisaka > >> first name at last name dot org or com > >> > >> _______________________________________________ > >> 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 > >> > > > > > > > > -- > > Ken Iisaka > > first name at last name dot org or com > > > > _______________________________________________ > > 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 > -- Ken Iisaka first name at last name dot org or com