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  1. #1401  
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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?
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  2. #1402  
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    Quote Originally Posted by Tom Hamilton View Post
    So how does Nikonos solve for this?
    By ditching the damn "porthole" altogether :)

    They were designed from ground-up to produce sharp, undistorted and flat images in the water. Correcting something that was not designed for the intended purpose is generally hard, impractical or often impossible.
    What impressed me most was the optical performance and tollerances, which surpass the performance of many modern terrestial lenses on land. I didn't know this before I actually measured MTF.

    What does it practically mean? Very crisp, flat, undistorted, high contrast underwater images. My current favourite is this one: http://achtel.com/DeepX/A004_R003_1119WH.001930.jpg . You are welcome to blow it up 1:1 and compare it with any other frame grab captured with any other underwater optics/camera...IMAX included and see what you think.

    For me, the cat has already been skinned :)
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  3. #1403  
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    Master Prime 14mm at f/5.6
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  4. #1404  
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    Gates Deep Red underwater housing for sale

    - Gates Deep Red underwater housing for RED One
    - Monitor housing for RED 5.6" LCD

    - RED 18-50 short extension tube
    - FE 486 long extension tube
    - Acrylic dome port
    - FP80 flat macro port
    - Moisture alarm
    - Tally light
    - Motorized zoom control
    - HD-SDI connection with 30m/100feet of cable
    - Submersible microphone w. mini xlr connector
    
- Gates Seal Check Unit
    
- Pelicase with custom fit hard foam (does not absorb water)

    Accessories:
    - Aperture scale for RED 18-50
    - Focus scale for Master Prime 14mm
    - White focus/aperture scales x2
    - Tool kit and o-ring kit, silicone grease, lens cleaning kit
    - Extra focus rods and gear unit support bars
    - Extra spare parts (screws etc.)
    - Extra replacement monitor cables x2 (new type)
    - Extra latches
    - Trim weights, internal and external

    Modifications:
    The battery cradle has been fitted with a second V-mount to allow 2x RED Brick (or similar) batteries running in parallel, doubling the power capacity. Mount was installed by factory technician at Hawk-Woods Ltd. in UK.

    General condition:
    The housing has been kept in good condition and shows moderate/normal wear, purchased new in August 2009. The acrylic dome and flat port need re-polishing, this is done by Gates to restore to better-than-new surface finish (included in sales price, turnaround time 4 - 6 weeks)

    Original purchase price in excess of $30.000,-
    Asking price: $12.000 / € 9.300 - OBO

    I also have RED One M-X #8966 for sale, new 08-2011, only 462 hours. Body with SSD module, Element Technica breakout box, 5'6" monitor and basic RED cast iron accessories. Asking price $5.000 OBO if purchased together with housing (excl. RED $500/$600 transfer fee).

    Shipping cost and arrangements TBD. I will be travelling to UK (London), USA (NYC, New Orleans and LA) during late July/August and can deliver in person. No cash sales.

    Please PM or preferrably contact me at:

    Amund Lie
    Ph. +47 901 77 070
    amundlie@mac.com
    www.hydrophobic.no
    Attached Images
    __________________________________________________ ___

    Amund Lie
    Norway

    www.hydrophobic.no
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  5. #1405  
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    SOLD!

    You guys have a new colleague in Romania :)



    Quote Originally Posted by Amund Lie View Post
    Gates Deep Red underwater housing for sale

    - Gates Deep Red underwater housing for RED One
    - Monitor housing for RED 5.6" LCD

    - RED 18-50 short extension tube
    - FE 486 long extension tube
    - Acrylic dome port
    - FP80 flat macro port
    - Moisture alarm
    - Tally light
    - Motorized zoom control
    - HD-SDI connection with 30m/100feet of cable
    - Submersible microphone w. mini xlr connector
    
- Gates Seal Check Unit
    
- Pelicase with custom fit hard foam (does not absorb water)

    Accessories:
    - Aperture scale for RED 18-50
    - Focus scale for Master Prime 14mm
    - White focus/aperture scales x2
    - Tool kit and o-ring kit, silicone grease, lens cleaning kit
    - Extra focus rods and gear unit support bars
    - Extra spare parts (screws etc.)
    - Extra replacement monitor cables x2 (new type)
    - Extra latches
    - Trim weights, internal and external

    Modifications:
    The battery cradle has been fitted with a second V-mount to allow 2x RED Brick (or similar) batteries running in parallel, doubling the power capacity. Mount was installed by factory technician at Hawk-Woods Ltd. in UK.

    General condition:
    The housing has been kept in good condition and shows moderate/normal wear, purchased new in August 2009. The acrylic dome and flat port need re-polishing, this is done by Gates to restore to better-than-new surface finish (included in sales price, turnaround time 4 - 6 weeks)

    Original purchase price in excess of $30.000,-
    Asking price: $12.000 / € 9.300 - OBO

    I also have RED One M-X #8966 for sale, new 08-2011, only 462 hours. Body with SSD module, Element Technica breakout box, 5'6" monitor and basic RED cast iron accessories. Asking price $5.000 OBO if purchased together with housing (excl. RED $500/$600 transfer fee).

    Shipping cost and arrangements TBD. I will be travelling to UK (London), USA (NYC, New Orleans and LA) during late July/August and can deliver in person. No cash sales.

    Please PM or preferrably contact me at:

    Amund Lie
    Ph. +47 901 77 070
    amundlie@mac.com
    www.hydrophobic.no
    __________________________________________________ ___

    Amund Lie
    Norway

    www.hydrophobic.no
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  6. #1406  
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    Auckland, New Zealand
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    Hey guys, just doing a bit of market research for a client. What brand wetsuits do you prefer for diving? Any features that are a must have for under water filming (I imagine you often are trying to extend your dive time longer than recreational divers might, and sometimes in harsher conditions)?

    How about dry suits? Any new innovations that you see coming that could help out your profession/diving in general?
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  7. #1407  
    Senior Member Tom Hamilton's Avatar
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    May 2009
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    Port Orange
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    Hi Craig,

    We are all hanging out on the new thread here;

    http://www.reduser.net/forum/showthr...-Blower-Thread

    rgds,

    Tom
    Dragon 6K 'Red Sea', Helium 8K S35 ‘Safe Passage’
    Gates Deep Weapon
    Hollis PRISM2 Rebreather System
    Red Sea Pictures
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