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16mm lens for JVC-HD200U? or super 16mm?
16mm is a 4:3, right?
So if you're using a 4:3 16mm prime lens with the JVC-HD200U (which is native 16:9) then isn't the lens blocking some of the image from the 16:9 CCD? Or maybe it doesn't work like that? Anybody? Seems like it would make more sense to use a Super 16mm lens. Like this:http://www.cookeoptics.com/cooke.nsf/secondary/sk4 |
Reimagers like the Mini35 and the new JVC unit can make the image any size they like.
The ground glass has to be a specific size to fit within the image circle that the 16mm lens projects, but the relay optics on the backside will size that groundglass image to the necessary size for the HD100 CCDs. In other words, no worries. |
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I'm really trying to AVOID using the mini-35 adapter, cinemek ect... I don't want to spend any more money than I have too. Not to mention the light loss and SIZE of 35mm adapters. Maybe I'm still misunderstanding how this works. I was under the impression that in unison with the NEW lens adapter (HZ-CA13U) I would be able to mount a 16mm cine lens DIRECTLY onto the camera. (NO GLASS IN BETWEEN). Is this correct? I can use Super 16mm cine lens in the same way? Or does the new HZ-CA13U adapter actually utilize relay glass itself? I envisioned it as a metal bracket that allowed PL mounting. Where am I missing? |
Chip size would still be small so 16mm lens depth will not look like the 35mm adapter depth. The PL mount is encouraging though. Will this camera have the same size chips as the 100?
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Even the DOF on 1/2" and 2//3" inch chips is not the same as 35mm. If you really want that look you will need to use and adaptor like the RedRock or get a full framed 35mm sensor.
However, being able to put on some high quality Super 16mm lenses which are very available on this camera is outstanding. |
Doesn't the JVC have a 1/3 inch sensor? I think the image area of 16mm film is slightly larger than a 2/3 inch video imager (16:9), so I'm pretty sure it'll cover. You won't be getting 16mm DOF though, and you may have back focus problems. The Panavision site (sorry, can't remember the link) has a PDF showing the size of various formats. You might want to check it out to help you visualize this.
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According to a JVC rep, the adaptor has a lens -- or lens system -- that provides a 0.46X image reduction. Which would be about right given your numbers. He claimed, there is no ground glass taget -- rather, the lens -- or lens system -- simply alters the light path coming from the mounted lens so that it lands on the CCD prism. Don't ask me if he's right about an adaptor working that way. It seems so obvious, yet too good to be true. |
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I'm asking because the handle is currently built into the video lens. |
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Is it possible to use a Super 16mm lens with JVC's new adapter? |
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Maybe I read the JVC press release wrong. I thought it said 16mm, not Super-16mm. I thought it'd make a difference? |
So does this mean the image will have the same characteristics as the Super16 lens -- DOF, angle of view, level of distortion?
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Which would be the better lens in general? The Super 16, or the 13x Fuji? What are decent lenses, and what might they cost?
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16mm lenses need to resolve accurately because the frame size is so small anyway, but it isn't as small as 1/3" CCD. I'm hoping the designers of the optics in this adapter have taken that into account. I can't wait to check this out with a good set of fast Zeiss primes. I imagine there are three distinct markets for this adapter: 1. Independent filmmakers comfortable with S16/16 as a format, but simply cannot afford the costs involved in stock/processing/transfer/optical blowup. 2. Television Productions already shooting S16/16. 3. Film schools with an inventory of 16mm lenses. Since the unit at the show was a mock-up/prototype there are still many unknowns: - does it truly maintain the field of view of S16 or 16mm? - will there be a stop loss (or gain?) - is it composed of pure optical elements or is some sort of relay lens with GG resolver? (indications are that it is unlike typical "mini35" style adapters.) -does it maintain the depth of field characteristics of the same lens on a S16/16 body? -does it require a backfocus adjuster? -what will the retail price be? (someone mentioned a price in another post, but I was told by Craig Yanagi they still do not know how they will price it yet or exactly when it will be released.) |
HZ-CA13U 16mm PL mount and the HD100
Is it safe to assume that the HZ-CA13U 16mm PL mount will work with the HD100?
Luis |
It will work, but the adapter was designed for the image flip feature in the new cameras. You'll have to flip in post if you want to use on the 100.
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I think Cineform might support image flipping during capture. They developed it for the RedRock Micro setup and this is similar.
btw, didn't Arri announce some new S16 primes at the show. Some of it's a blur with sensory overload. It was nice meeting you Nate, and you didn't run away screaming. I'm impressed.:) |
Would it be a "dream" or a true possibility to get from JVC a HD100 firmware upgrade to have that flipping capability? Anyways, right now we have the mirror image flipping capability in the current firmware (accessed through the service menu)...
Luis |
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"He claimed, there is no ground glass taget -- rather, the lens -- or lens system -- simply alters the light path coming from the mounted lens so that it lands on the CCD prism."
I thought of this approach a while back to get full frame FOV out of a APS sensor in a DSLR. I wonder if this is what they have done, cudos to them if they have. |
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Luis |
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Very nice in any case; there is some wonderful 16/S16 glass out there and this could open up a number of lens options, at least as far as zooms and telephotos go. Not too many 16mm lenses wider than around 8mm so don't look for too much on the wide end, but I've got a Zeiss 10-100 that I'd like to try, just to see how it holds up! |
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Luis, can you share with us how to do that? I've got access to Arri S16 glass and I KNOW I'm going to be needing this feature. |
"If that's the case, then it's functioning like a relay lens, or basically a re-focuser. This would not change the depth-of-field characteristics to match 16mm/S16, so the DOF would be identical to the existing HD100 lens at equivalent focal lengths"
Can you help me understand this please. My thought was that you are only resizing the area the image is being focused on with the lens (reducing it to march the 1/3" sensor, not changing the image itself. Therefore the lens would provide the same DOF and FOV as it would on a sensor it was natively designed for. |
DOP & FOV in the HZ-CA13U PL mount adapter
There is a lot of confusion surrounding this product, probably because it is not yet fully developed. But the way it was described to me by several JVC reps at the booth is that a lens on the adaptor will maintain the FOV and DOF characteristics that it has on a S16mm camera. For example, if you placed a 9mm Ziess Superspeed on this adaptor it would have a much greater FOV than you would get at 9mm on a 1/3" lens - more like a 4mm. It supposedly does this by using reducing optics that shrink the image so that you don't get the cropping that would occur if you were just using a physical adaptor, such as the Nikon. How they can do this without a ground glass is a mystery to me, but if true it is great news because it means that wide lenses on S16 would be just as wide on the HD100 and that there would be less DOP for the same relative frame size, since a longer length S16mm lens would be needed to achieve that frame size. (Hope this is clear).
The downside of the adaptor (as seen in it's current non-working prototype) is that it is about 5.5" long. I can't see mounting a zoom on it without getting a very front heavy rig. Also, they don't currently have plans for a handgrip. Of course, there are 3rd party solutions, but not with a record or focus assist button in them. In any case, hats off to JVC for attempting something that would be unheard of for most electronics companies. |
If you hold up a 35mm lens in front of a 1/3" video camera, it won't deliver the DOF of a 35mm camera. It still delivers 1/3"-caliber DOF, just upside-down.
It's adding the ground glass inbetween that allows the DOF to be resolved on the projection screen (ground glass), which the 1/3" camera lens (or relay lens) can then photograph. Now, if you put a still-camera lens right on a 1/3" camera body, you still get 1/3" DOF (witness the XL1/2 using the EOS adapter). So unless there's some manner of projection screen, it would seem doubtful that the DOF properties of the 16mm lens will be preserved. I don't know how the shrinking-the-frame element will affect this process; I can't think of another example of that offhand, and I figure that it will still deliver 1/3" DOF but you do raise an interesting point. Until the product's on the market we won't know for sure, so maybe they've worked some wizardry that does preserve 16mm DOF? |
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I've got my fingers crossed.
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I re-read that and agree with Andrew that the way I said it was confusing. I was referring to 10mm = 10mm, whether it's on a 35mm camera or a 16mm camera or whatever. I said it wrong and appreciate Andrew's clarification.
And yes, I think we'll have to see it in action to know exactly what it's doing. They said specifically no ground glass, right? So... I don't know what that means for the DOF characteristics. Was there any talk of the c-mount adapter? Or has this one replaced the potential c-mount adapter? |
The image on the screen "has" the DOF of the attached lens because the screen is placed where the film would be placed. And, I assume the image is the same size as it would be on film. Which raises a several questions.
1) There must be a downstream lens that focuses the image from the GG to the prisms and CCDs. Now if the GG image is the size of 16mm film frame -- then this lens would seem to need to reduce the image by 0.46X to get to the 1/3-inch CCDs. Which makes me think THIS is the lens the JVC rep. was talking about. 2) So perhaps he was wrong about no GG. 3) Since GG grain can be measured by an FFT. It is, in fact, noise. The finer the grain, the higher the noise frequency. The more uniform the grain, the more narrow the noise band. The fact JVC is developing the adaptor and the camera gives them the option for new approaches. In theory, this noise can be "notched-out" by a notch filter in DSP. Alternately, if the noise frequency is higher than image detail (the signal), then a very steep low-pass filter can remove it. This can be an optical filter or a DSP filter. 4) Reading reviews of several lenses, it appears these lenses produced a slightly "curved" image on the film plane. This works because 16mm film very slightly curves between perfs. So how does a flat GG deal with the fact that either the center or edges can be in focus -- not both. I assume the GG can be either set for center or edge focus -- or adjusted for either. |
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If you resize the apparent field of view of a lens optically through a magnifying lens, the depth of field becomes equivalent to whatever the new *effective* focal length of the lens is, not the focal length of the original lens. Believe me, a while back I thought it would be clever to try to shrink my depth of field by putting a wide angle adaptor on the end of my lens. I would then have to zoom in to get the same field of view, giving me a smaller depth of field, right? Err, well, wrong... At least I can shoot some nice wide-angle shots now. =D
This is why adaptors like the mini35 use ground glass. If you could just shrink the image optically and get the same depth of field, they would've done that and avoided all the hassles such as light loss that dealing with ground glass gives you. |
Well New Life for my Arri BL16 Lens
Its been a while since we shot with the Arri BL16, mow the lens wil be in use again, so guys moral of the lesson dont throw away your old stuff. I have already spoken to JVC dubai, cant wait to get the adapter and shoot some TVC, with GYHD 100 and the lens thats the end of my M2 experiment or is it.
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Here is a quick example of what can be purchased for use with the new PL adaptor
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I was told at the JVC booth that the idea of the PL adapter is that the horizontal FOV on a 16mm camera would be maintained AS WELL AS depth of field. I was also told that there is NO GROUND GLASS like similar third party products. So how is it done optically? We don't know because the unit being displayed at NAB was an empty glassless mock-up. I have also been thinking about depth of field and the calculations based on acceptable circle of confusion values and I am now starting to doubt that a 16mm image reduced to 1/3" HD will possibly maintain the depth of field characteristics on a 16mm gate. We simply won't know anything about this mysterious adapter until it is released. Here's my photos of it: http://www.timdashwood.com/.Pictures...HD200-PL_A.JPG http://www.timdashwood.com/.Pictures...HD200-PL_B.JPG |
Thanks Tim
[QUOTE=Tim Dashwood]The new adapter has PL mount though, not Arri BL mount. I'm sure a conversion could be done. We simply won't know anything about this mysterious adapter until it is released.
Lets see if this goes like Optex story and the nikon adapter, I just could not wait as I wanted to mount nikon lenses from day one even before I bought the GYHD100. Got in touch with Zoerk, and rest as we say is history. |
When is this going to be released? This sounds like a bit of a miracle if it works.
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