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Old December 21st, 2004, 12:52 PM   #31
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I not fixated on Foveon too. I just mentioned it without knowiing all the facts. But this thread still prove to be very useful in understanding greater knowledge of CCD.
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Old December 21st, 2004, 01:09 PM   #32
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<<<-- Originally posted by Balazs Rozsa : Not easy to do so. Current broadcast lenses are designed for a prism block. You would need to come up with a whole family of new lenses designed for your 1 chipper. -->>>

You could always use a lens mount that accepted 35-mm still or 16- or 35-mm motion picture lenses. Or you could adapt the optics used in the 10x and 12x zoom lenses found in some more expensive digicams. Would they be sharp enough for HD video? Probably. One photography publication ran resolution tests on 3.2-, 4-, and 5-megapixel cameras with these zooms; if memory serves, resolution peaked at about 1,500 line pairs, which is pretty close to the theoretical limit of a 4-megapixel single-chip digicam.
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Old December 21st, 2004, 01:25 PM   #33
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> You would need to come up with a whole family of new lenses
> designed for your 1 chipper.

Yes. But that's really a non-issue: especially if they use the 35mm frame size or similar. Canon has no trouble making lenses for their XL-series DV cams. And for a 35mm frame size they already have a wide range of photo lenses that can easlily be adapted. In a worst-case scenario --that is in the case of a new frame size-- it would just create a new market opportunity. It did for Canon.

And, because of the light sensitivity problem that they are already encountering with HDV, they will just have to move consumer and "indie" video to larger sensors at reasonable pricing. This is because higher resolution means lower pixel sizes at a given sensor size, and lower pixel size means less sensitivity.

The Sony FX1/Z1 HDV cameras don't even have full HD resolution yet and they are already much less sensitive to light than the Canon XL1 and the Panasonic DVX100.

My guess is that Sony, being able to do a much better job with a single sensor and MPEG2 than JVC, didn't want to confuse the market just yet. Sony already uses single-sensor RGB filter cameras in their high-end consumer segment with very good results. They just don't want al the Betacam customers to stop paying all the $$$ and buy the beter prosumer stuff!
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Old December 21st, 2004, 02:17 PM   #34
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Ha, saying 'digital film' is like saying 'horseless carriage.' I really can't wait for film to be dead for motion capture like it is for small format still cameras.
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Old December 21st, 2004, 05:13 PM   #35
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>>You would need to come up with a whole family of new lenses designed for your 1 chipper.

>You could always use a lens mount that accepted 35-mm still or 16- or 35-mm motion picture lenses.

I was talking about broadcast cameras because the camera in question was a $20000 camera.

If you are talking about consumer cameras I agree one chippers have a bright future. With only 2 megapixels 1 chip cameras could produce very nice 1 megapixel downsampled images. If you used a 1.8" hard drive to record 100Mb/s data from the camera at maximum 60 progressive frames a second, you would have an inexpensive Varicam.

The only problem would be you would need a computer to shrink the amount of data to a smaller size before arhiving your footage to DVDs. For example in the form of WMV9 files. But technically speaking such a camera would be quite inexpensive to produce (if high enough numbers could be sold) and still would give you quality images.

Kodak or Olympus could do it because they have nothing to loose in the high end video market
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Old December 21st, 2004, 06:17 PM   #36
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> The only problem would be you would need a
> computer to shrink the amount of data to a
> smaller size before arhiving your footage

Embedded soon enough. Who would have thought 3 years ago that Sony could pull off real-time high-res MPEG2 compression in something you can hold in your hand and pay with three month's worth of salary. So the computer is just a temporary nuisance.

> Kodak or Olympus could do it because they have
> nothing to loose in the high end video market

I agree and I would add Nikon to that list. Furthermore, I think JVC and Canon also have little to loose. And Sony and Panasonic will pretty soon have everything to loose if they don't switch their semi-pro and consumer line to HD and large sensors. It's better for them to self-cannibalize but at least keep the customers at less money then to let those other companies take away all their prosumer clients AND their pro clients.

It's like when the internet came along. The small companies that were able to adapt fast are the ones that were able to ride the wave and survive. Big companies like IBM and even not-so-big like Microsoft almost missed it. IBM actually lost it's practical monopoly on computing and had to become a niche player.
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Old December 22nd, 2004, 09:52 AM   #37
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I dont think, 3ccd systems will ever go away entirely

beacuse the way i see it is unless you find an alternative way to sample full colour information (1:1 pixel ratio) then you have to stick to 3ccd.

yes those full 35mm cmos/ccd images are excellent BUT who's saying that those images would not be even bettter if their was 3X 35mm full cmos/ccd..

problem is data..(or too much, to be precise) its hard enough capturing data from ONE 35mm sensor (connected to hard drive the size of a fridge ;)) things will get better in the future..
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Old December 22nd, 2004, 09:53 AM   #38
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I forgot about Kinetta, Don't know a lot about it. Not sure how close Jeff is to releasing a production model. I hope it's soon.

My reference to "digital film"(it's in quotes for a reason, punkin') is that Arriflex and Panavision's cameras are" film style" digital cameras. They are set up like and look like film cameras, they have optical viewing systems and use many of their respective film system parts and accessories, plus those of third party mfrs.

This makes the transition for film crews going from film to digital easier. There is a lot of money riding on these folks to get it right the first time, or else the producer is unhappy because the crew is "wasting money". There is a lot more going on on a film set than just shooting a film. So, user interface and user friendliness are paramount.

These people have a lot invested in Arri and Panavision film systems, both in knowledge and equipment that interfaces with these two systems-lenses, follow focus, remote focus, matte boxes, etc. It just makes sense to make them as similar as possible, that way the transition is smoother.

My main interest in a digial camera is as a professional DP. These are tools that I use on a daily basis for my work, that are (hopefully) viable technological steps forward. There are a lot of good things out there, but I take the wait and see approach. I look at what is going on and filter out a lot of the BS and see what will fit my needs and keep track of which way the film and video industries are going. unfortunately the best and the brightest are not always recognized or utilized; or you get the VHS vs Beta argument and whoever has the better marketing department wins.

For many jobs I am renting a camera because neither I nor the production can afford to own the higher end gear. For me as a DP, owning a film camera is one thing, the technology won't really change that much, it'll still take film and expose it twenty years later. Owning an HD camera seems risky, since the technology seems to change all the time. Plus I'm not that rich, yet ;~)

My answer to the original poster's statement of: "I don't believe 3 CCD's are needed anymore" is agreement, apparently not.
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Old December 28th, 2004, 08:17 PM   #39
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<<<-- Originally posted by Mark Sasahara : For me as a DP, owning a film camera is one thing, the technology won't really change that much, it'll still take film and expose it twenty years later. Owning an HD camera seems risky, since the technology seems to change all the time. -->>>

True enough about the HD cameras. As far as the film camera, well, I own a super-modified Arri 2c and I can't rid of it fast enough! (it's been in the shop for a year having a new video door built for it, which is taking forever). I know a lot of cameramen who have dumped their film cameras in the last couple of years; do you know Rob Draper, for instance?
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Old January 4th, 2005, 11:07 PM   #40
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Hi Charles! I like your work.

I know the name, but I don't think I've met Rob.

I think there will eventually be a technological stasis, my main point being that unless you have the bucks to keep re-investing in new video gear every few years, then, you're better off renting. I'm not getting that kind of work yet, but I'm definitely working on it, though.
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Old January 10th, 2005, 07:26 AM   #41
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Color accuracy is another major reason for 3CCD

<<<-- Originally posted by Balazs Rozsa : Actually for professional video 3 CCDs will be better for quite a long time because they have better light sensitivity.

If you build a 1CCD camera and a 3CCD camera using the same CCD chips and put the same lens in front of the cameras, in the case of the 1CCD camera the color filter will block about two third of the light that would go onto the sensors on the CCD. That means that the 3CCD camera will give the same noise and color clarity at about one third the light amount that is required for the 1 CCD camera to give the same noise and color clarity.
>>>

One factor people seem to be forgetting is the accuracy of determining the color of the object. Each resolved pixel of the final image will be defined as components of Red Green Blue light. How to determine how much of each RGB?

3-CCD - If you have a prism you can accurately split the light into beams of each color and put a CCD to capture each beam. Remembering high school physics class the prism does an excellent job of this. Light is split exactly by its frequency/wavelength. The CCD that captures Green for instance will not require the same dense filter to remove the other colors since the prism has already split the light beam and redirected the other colors to other CCDs.

1-CCD - If you have only one CCD you must paint a tiny color filter in front of each pixel to perform the filtering. So the cluster of RGB pixels are all together, little blobs of color allowing the 3 sensors to be sensitive to the different colors. but you are depending on a less accurate method to split the light into RGB. Also you have reduced the sensitivity to low light situations since you have essentially thrown away 2/3 of the light by absorbing it into the painted filters instead of spliting it up and redirecting it to the 3 CCDs of the other solution.

Just my 2-cents...

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Old January 10th, 2005, 09:38 AM   #42
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Re: Color accuracy is another major reason for 3CCD

<<<-- Originally posted by Paul Shard:
3-CCD - If you have a prism you can accurately split the light into beams of each color and put a CCD to capture each beam. Remembering high school physics class the prism does an excellent job of this. Light is split exactly by its frequency/wavelength. The CCD that captures Green for instance will not require the same dense filter to remove the other colors since the prism has already split the light beam and redirected the other colors to other CCDs.

1-CCD - If you have only one CCD you must paint a tiny color filter in front of each pixel to perform the filtering. So the cluster of RGB pixels are all together, little blobs of color allowing the 3 sensors to be sensitive to the different colors. but you are depending on a less accurate method to split the light into RGB. Also you have reduced the sensitivity to low light situations since you have essentially thrown away 2/3 of the light by absorbing it into the painted filters instead of spliting it up and redirecting it to the 3 CCDs of the other solution. -->>>

Example: white light coming in.
3ccd: 1/3 of the light is green and that gets into green ccd.
1ccd: 2/3 of the light is filtered from green pixel, so 1/3 of the light gets into green pixel.
Where's the difference just considering sensivity?
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Old January 10th, 2005, 11:03 AM   #43
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Re: Re: Color accuracy is another major reason for 3CCD

<<<-- Originally posted by Toke Lahti :
Example: white light coming in.
3ccd: 1/3 of the light is green and that gets into green ccd.
1ccd: 2/3 of the light is filtered from green pixel, so 1/3 of the light gets into green pixel.
Where's the difference just considering sensivity? -->>>

1ccd: 2/3 of the light is filtered from green pixel, so 1/3 of the light gets into green pixel. Plus for every other pixel which is not a green pixel the green light is not getting to the pixel at all. Overall 1/6 of white light.

For red and blue only every fourth pixel is red or blue so the ratio is even bigger.
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Old January 10th, 2005, 11:29 AM   #44
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Re: Re: Color accuracy is another major reason for 3CCD

<<<-- Originally posted by Toke Lahti :

Example: white light coming in.
3ccd: 1/3 of the light is green and that gets into green ccd.
1ccd: 2/3 of the light is filtered from green pixel, so 1/3 of the light gets into green pixel.
Where's the difference just considering sensivity? -->>>

I think it is as follows... the 3CCD is noticeably more sensitive - somewhere in the neighbourhood of 3 times because the sensors are much smaller in the 1CCD camera - less light gets to them (a bit better than 1 f-stop sensitivity improvement)

3CCD - each CCD in this system is say 1/3 inch. Imagine it divided as a grid 720 by 480 pixels (for normal DV camera). Each pixel represents one pixel of the image in the one color (say green). There are 345,600 pixels in each CCD so each sensor receives 1/345600th of the total green light. But the prism redirected 2 thirds of the light to start with so we could say 1 millionth of the total light will hit the green pixel in question.

1CCD - for our 1/3inch camera there have to be three sensors in each of the locations to make up the image. Each with a filter. So total sensors on the chip are 720*480*3=1036800 sensors. Therefore 1 millionth of the total light hits our same green pixel. BUT the filter now removes the red and blue light leaving 1/3 of a millionth of the total light.

As I reread this it seems needlessly complicated and potentially confusing. anyone feel free to chime in with a simpler explanation :-)

Maybe another way to see it is that all the light entering a 3CCD camera eventually hits a sensor but 2/3 of the light entering a 1CCD camera is absorbed away by filters and never strikes the sensors.

Paul
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Old January 10th, 2005, 01:11 PM   #45
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To make it a little more clear (I think)...

1CCD - the color filter throws away 2/3 of incoming light before hitting pixel

3CCD - the prism deflects 2/3 of light away from each CCD & towards the others. Than all three CCD's charges are processed (combined) into one signal.

Is that right?
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