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35mmor 2/3" lens, 1"CCD, 33 1/3% reduction in sensitivity


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#1 Glen Alexander

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Posted 19 January 2008 - 02:43 AM

Am looking for those guru who have actual experience using these lenses not just the theory, thanks.

Please check my math to see if I have made a typo or had a brain cramp. :) converting units into film lingo to get the proper lenses.

No PL mount glass please.

Sensor is 1", HD, mono

When used in a particular configuration, the sensitivity of the CCD is reduced by ~~33 1/3%.

Configuration reduces the available aperture required by 0.63093 stops?

Case 1.
Glass 2/3" Fujinon Cine HD
Lens are made for 2/3" sensor, Fujinon Super Cine, C-mount

Since the lens is made to project a 2/3" image which decreases the effective focal length.

Case 2.
Glass 35mm Nikon photographic lens, F-mount.
Since the lens is made to project a 1.378" image, the focal length is increased.

Questions
for case 1,
If my original shot requires a 100mm, F3.

1. is the Fujinon glass good enough past 2/3" of an inch to produce useable images? "good" meaning no horrific distortions, fisheyes, etc.

if not, are there other glass mfg that do produce product that will?

which yields better 'quality' images for

2. compressing the DOF?

3. super wide angle, NO fisheye, how long can one go?

4. prime lens 200mm or greater? F4.5/6

5. prime 100mm lens?

6. zoom lens 25-100mm?

7. zoom lens 55-200mm?
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#2 David Mullen ASC

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Posted 19 January 2008 - 03:49 AM

Your question is extremely confusing. Can't you be more specific? What is a 1" HD mono camera and why are you putting a 2/3" lens on it and what circumstance would cause you to lose 1/3 of the sensitivity?????

If you put a 2/3" lens on a 1" camera, you will have to crop the sensor area to get rid of the vignetting, so are you asking if the 2/3" lens is good enough or if the camera is good enough to survive the cropping to a 2/3" area?

Could you rephrase your questions? I don't even know what you mean by "requires 100mm at F/3" -- you want to use a 100mm lens on a 35mm-sized sensor? Or do you want to use a 100mm 2/3" HD lens? Why at F/3? Why 100mm?

What are you asking???
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#3 Glen Alexander

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Posted 19 January 2008 - 04:43 AM

Your question is extremely confusing. Can't you be more specific? What is a 1" HD mono camera and why are you putting a 2/3" lens on it and what circumstance would cause you to lose 1/3 of the sensitivity?????

If you put a 2/3" lens on a 1" camera, you will have to crop the sensor area to get rid of the vignetting, so are you asking if the 2/3" lens is good enough or if the camera is good enough to survive the cropping to a 2/3" area?

Could you rephrase your questions? I don't even know what you mean by "requires 100mm at F/3" -- you want to use a 100mm lens on a 35mm-sized sensor? Or do you want to use a 100mm 2/3" HD lens? Why at F/3? Why 100mm?

What are you asking???

Hi David,
Sorry to be confusing. The CCD is a 1" array, you can either get a C-Mount from the factory or an F-mount, a PL-mount would probably crash into the sensor without a serious or very expensive modification.

The CCD array can be operated in color but then you have to deBayer/demosaic the resulting images, the demosaicing process 'throws' aways pixel so the number of effective pixels get substantially reduced. If you operate the CCD in mono mode, no deBayering/demosaicing, you don't lose as many pixels but the sensitivity of the pixles in mono is reduced as they still have the filters on top of the array.

Yes i'm asking if the 2/3" fujinon are good enough or the image will have to be cropped severely. or are there other 2/3" lenses that are better but not seriously more expensive? I want to make indie films and budget is a concern, but I do want quality but quality I can afford. I can afford fujinon and Nikon glass or similar .

I choose the 100mm F3, aritrarily, as the choice of lens will have to compensate for the sensitivity of the sensor dropping by 33% as well as a lens that doesn't quite match the sensor area.

Maybe I completely missed in my search for good 1" lenses in C- or F-mount?

cheers

Edited by Glen Alexander, 19 January 2008 - 04:47 AM.

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#4 Glen Alexander

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Posted 19 January 2008 - 04:53 AM

so if the shot is originally calls for a traditional 35mm PL-mount, 100mm, F3, daylight. how would i get close to this as possible with either a 2/3" fujinons or 35mm Nikon glass with a 1" sensor that has reduced sensitivity by 1/3.

Thanks for quick answer!!! :)

Edited by Glen Alexander, 19 January 2008 - 04:57 AM.

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#5 Michael Nash

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Posted 19 January 2008 - 02:40 PM

2/3" video lenses are made to be used with prism-block cameras. On a "flat" sensor there will be chromatic distortion.
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#6 Glen Alexander

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Posted 20 January 2008 - 12:08 AM

2/3" video lenses are made to be used with prism-block cameras. On a "flat" sensor there will be chromatic distortion.

Hi,

Thanks for the post.

How bad will the distortion be with the Fujinons? Are there better lenses? If the distortion isn't too bad, I can write an algorithm to correct for it. Can you quanitify or post an image of the distortion?

cheers
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#7 David Mullen ASC

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Posted 20 January 2008 - 12:18 AM

Why not just use a 2/3" 3-CCD camera with the 2/3" Fujinon HD lens?

I'm not sure why a 1" sensor camera has a C-mount -- C-mounts are mainly used for 16mm cameras and a few small video cameras. So why build a camera with a 1" sensor and then put a mount on it for lenses not meant to cover a 1" sensor? What was the manufacturer thinking???

Either way, a C-mount lens or a 2/3" video lens, are both designed only to cover a smaller area, so why not use a camera with a 2/3" 3-CCD sensor?
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#8 Glen Alexander

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Posted 20 January 2008 - 12:30 AM

Why not just use a 2/3" 3-CCD camera with the 2/3" Fujinon HD lens?

I'm not sure why a 1" sensor camera has a C-mount -- C-mounts are mainly used for 16mm cameras and a few small video cameras. So why build a camera with a 1" sensor and then put a mount on it for lenses not meant to cover a 1" sensor? What was the manufacturer thinking???

Either way, a C-mount lens or a 2/3" video lens, are both designed only to cover a smaller area, so why not use a camera with a 2/3" 3-CCD sensor?

Hi David,

Thanks for the post.

Cost is the main issue with a 3-CCD camera. Secondary concerns are size and weight.

I plan on doing some real remote shots and need something rugged and that doesn't break my back lugging around as well as being able to power with a small solar panel.

I'm not concerned with recording audio on the sensor like Sony EX-1. I'm quite happy with a small, portable DAT.

The sensor is going to cost about $4.5k USD, the acquistion, command/control laptop about $2.0k.

Why the mfg would put a C-mount on the sensor, to be honest I can only guess for low cost lenses and compatability with their other existing and current products? otherwise I don't have a clue. :)

Thanks for the feedback, great to get the details worked out of these issues .

cheers

Edited by Glen Alexander, 20 January 2008 - 12:31 AM.

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#9 David Mullen ASC

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Posted 20 January 2008 - 12:45 AM

Why not buy the Sony XDCAM-EX and a bunch of batteries?

Why mess with this DIY set-up? Your laptop needs power too anyway.
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#10 Glen Alexander

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Posted 20 January 2008 - 01:22 AM

Why not buy the Sony XDCAM-EX and a bunch of batteries?

Why mess with this DYI set-up? Your laptop needs power too anyway.


Hi David,

I've read so much on both sides about Sony/Cinealta type systems on this forum and others, people for and against. People bashing it for this reason, praising for this, it's difficult for me to see that there is a consensus to be honest.

I guess it is what you are comfortable with. I've used Balser, Dalsa, Pulnix in scientific, applications, ultimate DIY :) I find it 'simplier', then the myriad of buttons, settings, that confuse the hell out of me ha ha. I am a fan of the simple and straightforward, do the math for your lighting, lens, DOF, FOV, fps, and 'hit the button'. I have a good understand of the optical 'basics' not all of the whiz bang buttons, zebra patterns, modes etc. ha ha not that I'm opposed to learning a new trick mind you.

The sensor only needs ~4/5 Watts under full load. The laptop can perform for 2 to 3 hours under full load and needs about ~70/85W, ~50W or so 'idle', maybe ~10W?? or see "sleeping". Numbers could be off will have to check the spec sheets.

Thanks for posting.

Cheers
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#11 Brian Wells

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Posted 30 January 2008 - 09:28 PM

Balser, Dalsa, Pulnix in scientific, applications... I find it 'simpler'

Hi,

For *most* cinematographers, that method is not simpler, IMHO. Hope this helps!
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#12 Sam Wells

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Posted 31 January 2008 - 10:56 AM

I'm not sure why a 1" sensor camera has a C-mount -- C-mounts are mainly used for 16mm cameras and a few small video cameras. So why build a camera with a 1" sensor and then put a mount on it for lenses not meant to cover a 1" sensor? What was the manufacturer thinking???



I think there are "industrial" C mount video lenses that cover 1" --- I know we had a Hitachi 1" Vidicon camera used as video assist on a snorkel rig, it was C mount.....

-Sam
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Visual Products

Media Blackout - Custom Cables and AKS

Metropolis Post

Ritter Battery

Technodolly

Abel Cine

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Willys Widgets

Glidecam

CineLab

Opal

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