In message <>, Please stop referring to concentric RGB sensors as "Foveon" or "The Foveon idea". Millions of people had the idea before Foveon; in fact most people who know that color graphics use formats with separate RGB would naturally assume that all three are sensed for each pixel, unless they heard of the bayer CFA. Foveon is merely a company that promised to make the basic universal idea a technological reality, but have failed to do so with any level of quality in terms of providing data from which color can be easily or accurately interpolated. --
In message <bqh0ns$k4r$>, Nonsense, liar. Nobody assumed that Foveon had the same sensor pattern as a Bayer. Some may have called the full RGB triplet a single sensor (as in, "an RGB sensor", but no one assumed anything less than three colors being detected at each coordinate. Everyone who knew of Foveon knew it as something different because it did have RGB at each coordinate. No, this whole thing started because you came in here with insane claims, just like you used to do with the Amiga in another newsgroup. It's not efficient at all, that's the problem. The overhead involved in trying to get a full-RGB concentric sensor makes high resolutions a great technologial challenge, and it really isn't worth it with current technology, because for the same cost you can make a bayer with less channel sensors than a Foveon that captures more real detail unless the subject is an unlikely high-frequency big change of hue with little or no change in luminance. Sigma decided to make up for the lack of resolution by omitting not only an anti-alias filter, but even microlenses, making the images appear "sharp" with artifacts when sharp lenses are used. This false SD9 sharpness at the pixel level is your rock of hope, as the SD9 images at 1:1 pixel viewing on a monitor have more "zing", but unfortunately, this zing is not from real detail, but from artifacts. Yes, high-frequency details below the nyquist are more pronounced with the SD9, but they are also polluted with detail from above the nyquist, which you can not filter out without filtering out real detail as well. --
In message <bqknsl$p3o$>, No, I think what you are looking for is "The SD9 takes 10.3M samples in 3.43M unique spatial sensor coordinates". --
In message <3fccf26e$0$204$4all.nl>, Please don't call concentric RGB triplets "the Foveon concept", or "the foveon idea', or "foveon". They didn't invent that idea; it is a basic intuition. _Their_ idea was to make this basic intuition a technological reality, and they have failed to deliver quality goods. They have not found a way to filter light so that it charges the photosites in the correct layer. --
In message <>, Obviously, there is no need to filter color aliasing with a Foveon, so the anti-aliasing filter can be weaker. The Sigma SD9, however, not only has no anti-aliasing filter at all, but doesn't even have microlenses to direct the light that would hit the surface of the sensor between photosites into the photosites. The result is that the SD9 is a mean, lean aliasing machine. --
http://www.dpreview.com/news/0306/03062502leicadigitalr9.asp Check the specs: - No anti-alias (blur) filter. You just called Phil Askey an idiot. Also see... http://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&q="blur+filter" +bayer
There are loads of full color sensor cameras on the market, only a few are made by Foveon. The advantages are well understaood by all in the know, and they are considered utterly dominant designs compared to thier single chip counterparts. Foveon may have pioneered the 3 chip camera, but today there are many. The Foveon Pro 10M sensor is only revolutionary in that it brings this universally understood (in photography circles, not here) extraordinary advantage to a DSLR, by fabbing all 3 chips (now layers) on a a single die.
Same for all sensors (individual) including Foveon's. Just look at the channel breakdown of any image. So bottom line, it doesn't matter since it is the same for both and Foveon will get (10.3/6.0)X as much "extra" luminance as a 6M sensor Bayer, any way you figure.
It does. It generates full previews that can be zoomed-in to the pixel level, unlike the unusable S2 Pro in RAW mode which only shows a tiny preview image. The SD9 doesn't store images as JPEGs because the JPEG format itself causes too much harm to a single-pixel-resolution image (it does the same to Bayer images, but they are too blurry to care with a 4-pixel minimum resolution). And TIF is too big. Cropping is not magnification, just like digital zoom isn't optical. The test is perfect.
Just like every Bayer DSLR user here originally thought they actually had more sensors in their very low sensor count cameras, than in the 10.3MP SD9. Many here generuinely thought the vastly superior SD9 had lower resolution than a truly puny 3MP Bayer, not having seen this, I guess... http://www.pbase.com/pennychallenge
The image is a mass of noise. Check the channels. Each channel has a different pattern of intensities, even in areas that should be smooth. It's really bad, probably one of the worst digital images I've seen. Note also the serious smearing of colors in areas like the trees. Unless you shot that picture in a snowstorm, it's a mess.
Agreed, but using the silicon absorption characteristics to separate the spectral bands in a single chip is IMHO a new concept, i.e. the implementation of it. The absorption characteristics were of course know already, like e.g. the better penetration by long wavelengths such as IR. RGB triplets from single shot cameras on the other hand have already been in use for a long time, nothing to do with the particular sensor being discussed here. Bart
No it wont !! The sd foevon sensor is only 3.34 mp, the cannon 6 mp. So you do get 6 mp worth from the cannon, but only 3.34 mp worth of luminance date from the sd foevon. "Only a Gentleman can insult me, and a true Gentleman never will..."
Sounds like they are saying each discrete/independent position can be used without any of the others. That's fine if you want a single 3.4MP image, such as a very good black & white image. You just need data from all THREE colors to make up ONE co-lated sample. In essence, it takes 10.3M of data to make up a 3.4M RGB array.
In message <bqn4ht$e0g$>, No, what they thought was that a 6mp bayer sampled from more locations than a 3.43mp Foveon, and they were right. The SD9 has 10.2M sensors. It only has 3.43M pixels. They all look horrible. Every one of them. This test is out of the scope of < 24*36mm sensors. Yours has more contrast because your penny has more contrast, and because your camera aliases. If I did not know that Lincoln pennies started in 1959 and had dates on them, I wouldn't have any idea what the date on your SD9 sample was (not even that it was a date). --
In message <bqn3ms$dn2$>, The theoretical advantages. The actual chip is not working out, and it is used (or rather, abused) in a Sigma cameras that try to cheat the laws of sampling, and capture aliasing artifacts. --
power cells have been using the 'double well' (gathering the charges at two different levels in the silicon) technique to increase the power generation for a while. There have also been sensors used to measure the wave length of light, though they have never been put together in an imaging area before Foveon. (Well to my knowledge, which admittedly is not vey extensive.) When I did a search on 'silicon absorption' I turned up quite a few devices that exploited the fact that the absortion lenth in silicon is frequency dependent.
Furthermore, it doesn't stop all frequencies above that zero. The response has zeroes at all multiples of the sampling frequency but (admittedly diminishing) finite transfer at intervening frequencies. E.g. 3/2 * the sampling frequency will be attenuated somewhat, but still passed. /JB
