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Pawel Achtel
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Sorry to burst your bubble, Tom, but...
This has already been attempted by Leif Samuelsson back in 1998. Here is a copy of his research paper: http://home.swipnet.se/marinls/domeuw.html
However, such solution has some fundamental problems other than manufacturing, which Leif pointed out in his research:
The image plane curvature for a given dome port and angle isn't constant. It changes depending on the distance of the subject from the lens.
The objects close to the dome are projected on a surface of a virtual sphere, but objects further away are mapped on a slightly flatter, but also curved surface. Not only those surfaces have different curvature, but they are also not aligned, causing compression of "depth" dimension.
While theoretically possible to overlay, the MTF of human vision would be relatively insignificant compared to that of 4k sensor and normal/wide viewing angles. The acuity of central vision is very high, comparable to about 160 Megapixel array. As we watch images, our eyes constantly scan the area, effectively requireing even higher MTF from corner to corner. So, we are not even close to the limits of human vision. Although 4k may be getting close enough for practical reasons.
A 10" dome is not that different than an 9" dome. CinePort has curvature of 12". You would need a 32" dome to minimise the image plane curvature on a 30mm sensor to similar levels as we had using 2/3" HD sensors with an 8" dome. But, even then, image plane curvature would present problems at large apertures and wide angle of view in 4k.
Not sure why you think that Nikonos is "far from ideal". To me, it seems to be as close to ideal as it gets: it is small and compact, it does not require gears or servos, it can be changed in seconds, it out-resolves the sensor at 5k from corner to corner (not many terrestial lenses can achieve this on land!), it performs exceptionally well wide open, it produces perfectly flat image, it doesnt' cause vignetting, it does not create geometrical distortions, it doesn't flare easily (BTW, speaking of flaring, Have you seen Howard Hall's footage of humpback whales?), it produces high contrast images, it doesn't suffer from chromatic aberrations or astigmatism, the manufacturing was to very strict tollerances and back focal distance is generally spot on, and, best of all, they are inexpensive!
There is also a good selection of different lenses ranging from 12mm 170-degree fisheye to 80mm and anything in between, including all RS lenses that we can use on standard Nikonos mount with an adapter. That's pretty close to ideal to me You can even put a dome port and any manual Nikon lens on it for split shots.
But, for me, the biggest advantage is the ability to mout two of those lenses side-by-side or in a wet beam splitter. How do you shoot 3D with two 10" domes?
This has already been attempted by Leif Samuelsson back in 1998. Here is a copy of his research paper: http://home.swipnet.se/marinls/domeuw.html
However, such solution has some fundamental problems other than manufacturing, which Leif pointed out in his research:
The image plane curvature for a given dome port and angle isn't constant. It changes depending on the distance of the subject from the lens.
The objects close to the dome are projected on a surface of a virtual sphere, but objects further away are mapped on a slightly flatter, but also curved surface. Not only those surfaces have different curvature, but they are also not aligned, causing compression of "depth" dimension.
While theoretically possible to overlay, the MTF of human vision would be relatively insignificant compared to that of 4k sensor and normal/wide viewing angles. The acuity of central vision is very high, comparable to about 160 Megapixel array. As we watch images, our eyes constantly scan the area, effectively requireing even higher MTF from corner to corner. So, we are not even close to the limits of human vision. Although 4k may be getting close enough for practical reasons.
A 10" dome is not that different than an 9" dome. CinePort has curvature of 12". You would need a 32" dome to minimise the image plane curvature on a 30mm sensor to similar levels as we had using 2/3" HD sensors with an 8" dome. But, even then, image plane curvature would present problems at large apertures and wide angle of view in 4k.
Not sure why you think that Nikonos is "far from ideal". To me, it seems to be as close to ideal as it gets: it is small and compact, it does not require gears or servos, it can be changed in seconds, it out-resolves the sensor at 5k from corner to corner (not many terrestial lenses can achieve this on land!), it performs exceptionally well wide open, it produces perfectly flat image, it doesnt' cause vignetting, it does not create geometrical distortions, it doesn't flare easily (BTW, speaking of flaring, Have you seen Howard Hall's footage of humpback whales?), it produces high contrast images, it doesn't suffer from chromatic aberrations or astigmatism, the manufacturing was to very strict tollerances and back focal distance is generally spot on, and, best of all, they are inexpensive!
There is also a good selection of different lenses ranging from 12mm 170-degree fisheye to 80mm and anything in between, including all RS lenses that we can use on standard Nikonos mount with an adapter. That's pretty close to ideal to me You can even put a dome port and any manual Nikon lens on it for split shots.
But, for me, the biggest advantage is the ability to mout two of those lenses side-by-side or in a wet beam splitter. How do you shoot 3D with two 10" domes?