Simple question:

Started Jan 12, 2013 | Discussions thread
Usee
Senior MemberPosts: 1,517Gear list
Like?
Re: Simple question:
In reply to Richard Franiec, Jan 14, 2013

Richard Franiec wrote:

Would you buy Foveon sensor implemented into Canon 5DMkIII (or if you like Nikon D800) and if not, why?

Cheers,

Richard

Answer: NO

...because I like light weight bodys with good ergonomics like the Samsung NX20, or the Panasonic GH3 (which has the maximum weight I would accept nowadays for a body without lens).

Furthermore I would not want a FF sensor due to the need of bigger and heavier lenses...

...I would buy a camera with a revised layered sensor with the sensor size not bigger than I described here:

http://forums.dpreview.com/forums/thread/3034332

...and with top notch high resolving light weight lenses.

-

It is quite simple, why a layered sensor with the actual Foveon design is loosing his advantages with the higher pixel density and the size we already have in the SD1 generation and therefore the DP3M (due to its probably further optimised lens) is probably the most appealing camera in the sense of the Foveon concept at that high pixel density (without looking at the drawbacks of the body design):

1. the airy disk of red light at 760 nm is twice as big as the blue one at 380 nm - at the same aperture setting...

...resulting in a red airy disk spread over the area of 4 Foveon pixel whilst the blue one has only the size of one pixel at the same aperture setting...

...thus the need for extra sharpening the red channel and loosing the one pixel - all true color information - advantage:

http://forums.dpreview.com/forums/post/50578456

This also applies to Bayer pattern sensors, but this type of sensor is used to combine the information of several pixel sites.

Therefore the need of a more narrow band pass filter to reduce this problem (like introduced with the DP1s) is not that important for Bayer pattern.

2. the smaller the pixel size the higher the demand on the lens quality and the chosen aperture setting, to avoid single pixel information degradation due to additional light spreading over several pixel...

...especially in the corners of layered sensors due to the deeper, seperate buckets within a pixel which a layered sensor needs and which make it even more complicated to concentrate a coloured airy disk consisting of airy disks with different sizes (depending on the wavelenght mix for a certain colour) in one pixel.

The bigger the angle of incidence of the light, the bigger the color shift, vignetting and the noise in the corners of the frame - loosing the single pixel advantage even more, if the lens design is not highly optimised...

...therefore third party lenses like M42 lenses or older Sigma lenses already show more problems than the DP2M, which also shows slight problems despite the optimized lens and the software corrections:

http://forums.dpreview.com/forums/thread/3354783?page=3

3. I think that the DP3M probably has the most optimized lens for those issues,

but those issues will remain, simply due to the real existing limitations of optics:

The different sizes of airy disks depending on the wavelenght and aperture setting.

Thus, I would buy a Foveon camera like the DP3M if it has a lens which is able to resolve about 1.4x the nyquist of the sensor - even in the corners of the frame - and which has the option to use specialised AA-filter and or different (band pass / IR) filter on demand...

...supported with proper, customizeable software.

...a niche product for sure, but isn't Sigma Foveon all about niche products - exept lenses?

-

11 MP sensor and a lens even wide open (at F 2.8 or faster) suited for more than 15 MP...

...that would increase the single pixel quality (contrast, sharpness, dynamic range, noise, color etc.), processing speed and battery life - even without changing anything else!

-- hide signature --

Envy is the highest form of recognition.
Stop to run, start to think.
Think twice - that doubles the fun!
Your world is as big, as Your mind.
Avoid to have only one point of view!
Uli

Reply   Reply with quote   Complain
Post (hide subjects)Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow