Archived posting to the Leica Users Group, 2018/04/03
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Howard this was the kind of thing I was trying to communicate though doing a
poor or unclear job. I'm kind of like those pixel sites. Corrupted by too
many other influences.
--
Mark William Rabiner
Photographer
?On 4/3/18, 10:36 PM, "LUG on behalf of Howard L Ritter Jr"
<lug-bounces+mark=rabinergroup.com at leica-users.org on behalf of 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.
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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
_______________________________________________
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