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-   -   DV953 uses Pixel Shift Technology (https://www.dvinfo.net/forum/area-51/9491-dv953-uses-pixel-shift-technology.html)

Boyd Ostroff May 11th, 2003 03:57 PM

Somewhere I though I read that pixel shifting helped to give more of a film grain effect, as opposed to having them all aligned in the same rows and columns.

Frank Granovski May 11th, 2003 04:13 PM

>The guy at DV.com retersted the camera after reading the manual and said that the image is amazing.<

But wait, the story continues. Now he wants to return it and buy a TRV950, because it's got better 16:9 and 1/2 a LUX more (?) Also, he inferred the 953 is too complicated, that's why he still uses Ataris. Go figure. (That's why I'll never sell my DVL9500 cams. It don't matter, not even in a 24P HD world around the corner. I'm keeping them, and they're going in the grave with me!)

Joseph George May 11th, 2003 07:16 PM

Pixel shifting or not -- do some search on the Net guys -- I learned it in a Kodak seminar; once you shift the pixels it becomes a 1-CCD camera colorwise -- the colors need to be aligned precisely to take advantage of the 3-CCD system. CineAlta and Varicam are aligned precisely; the other ones -- I don't know. But on DV it does not really matter much. One CCD or 3 CCDs -- it does not make much difference because of the color compression.

Frank Granovski May 11th, 2003 07:55 PM

Joseph, video is far more forgiving than film---especially stills. Trust me. Even bad video can look good, not so with pictures.

Masaki Kuraoka May 12th, 2003 09:43 AM

Dear everyone.

I am getting dizzy reading all these posts.

But I thought DV953 / MX5000 use image shift only when you take still pictures. It doesn't use image shift when you take movies.

Am I correct on this?

I am not sure why Joseph is saying that DV953 isn't true 3CCD Camcorder.

DV953 has enough resolution to take movies (800k x 3 CCD) without shifting image and DV953 uses 3CCD to enhance 800k image to 3meg still pictures. Of course it isn't true 3meg pictures, that's because CCD is only 800k size. Image shifting enables 3meg pictures.

Jeff Donald May 12th, 2003 10:40 AM

This thread is going around and around.

First, why should I trust the subjective visual observations of someone who buys cameras with the sole intent of just playing with them and returning them. This is suspect in my opinion, along with his testing methods.

Second, Joseph, can you provide a link to some other source for your contention that 3 CCD's act like 1 CCD when pixel shift technology is employed? If Kodak brought this up at a seminar it must be published somewhere. If you can't find a link to substantiate your claim, then I think people are getting confused over nothing.

Joseph George May 12th, 2003 11:54 AM

Guys, I'm leaving town -- starting new project; don't have time. Kodak is quite advanced in CCD technology and quite helpful. Get on their site. They must have something to that effect. Do search on Google or maybe Kodak site on: Kodak CCD theory, operation, engineering, or something. I want to stress that it does not really matter much if you use 1 or 3 CCDs, especially not in DV, MPEG2 Micro DV, MPEG2 DVD, or MPEG2 HD DV. The colors are significantly compressed. It would make the most difference on 4:4:4 color system, where there is no color compression. On 4:1:1 and 4:2:0 systems you compress chroma (color) 4x compared to luma (B/W), so it does not really matter. Once you get to megapixel CCDs with resolution a lot higher than the format, it matters even less. Dalsa is 8 meg camera and is using 1CCD. Using 3 CCDs on consumer cameras has more to do with marketing and being able to take good stills. Anyway the 953 seems to be a nice camera from what the guy on the other board says and because of the manual controls it probably is the best buy in that price range, followed by PDX10, DVX100, HD10, if JVC fixes up the color problem. Al these are nice cameras for video production where you have enough light, with lux rating 15 for 953, 7 for PDX, 24 in progressive for DVX and 35 in HD for HD10. DVX is 3 Lux in interlaced but I'm adding it here because of the progressive mode, where it has increased subjective resolution over DV. 953 and PDX have increased 16:9 resolution. HD10 is HD.

Andre De Clercq May 12th, 2003 12:03 PM

Joseph, I don't understand were you get all those "strange" thoughts. (Green) pixels shift techniques have been patented about 20 years ago and has been accepted in the pro cam world as a method which allows the difficult trade-off of optical aliasing vs luma resolution limits for a given (3CCD) structure to be shifted towards a higer luma resolution picture. If you persist in yr belief that this structure is a 1 CCD equivalent you must at least know that yr 1 CCD has 3 times times the surface and fill factor(sensitivity) and three times the amount of pixels (resolution) and most important that you have to invent a 1 CCD structure with partly overlapping pixel structures(which is optically the case in 3CCD pixel shifted structures), not co-sited like in 1CCD devices with filter.

Joseph George May 13th, 2003 10:27 PM

Got tired of explaining this. We are basically recording luma and 2 compressed chroma signals. On one CCD system you get these signals off of a single chip and there is a space shift among the pixels whose signal you use to combine into signal to be recorded. That is the reason that 3 CCD's are used, so you get the signal from all 3 components at the same time, in the same space. You use these signals to create the 4:1:1 signal. If the CCD does not have enough resolution for the format, like on Canon XL1/XL1s, the manufacturer selects to use physical shift among pixels. This allows higher luma resolution, but worsens the color resolution.

Example. There is a boundary of blue and green in the picture. On a true 3 CCD system all 3 sensors will see the same boundary. On a shifted pixel sensor, near the boundary one color sensor may se the blue, one the green, and one half of each. By combining these signals, of 3 sensors that are not at the same location, you get inaccurate color. It is that simple.

All 3 of the 4:2:2 signals are recorded simultaneously so you need to feed them with simultaneous information that is same in space and time.

As I said, in DV it does not really matter much. But the 3 physically shifted CCDs do resemble 1 CCD less the double green pixel count. The color accuracy is equal to 1 CCD sensor. The large pixel count naturally helps.

I had the camera quality backwards in my previous post. The low end is 953; the high end is HD10.

Jeff Donald May 13th, 2003 10:44 PM

Since you're back in town from your project can you find a link to substantiate your post, please? I searched Kodak's site and found nothing. I hope you'll have better luck.

Frank Granovski May 14th, 2003 12:59 AM

Just to continue the other story, the dv.com member, Lyonhart, exchanged his faulty PV-DV953, and now is happier (with the replacement). All those thousands and thousands of words he wrote, and complaining about the wasted days used to write these words, it never dawned on him that there was something wrong with his cam. Go figure!

Joseph, you are dead wrong. Andre De Clerq already explained why; and I value all his posts, since he knows what he's talking about, all of the time. He is our Adam Wilt and Peter Utz.

Joseph George May 14th, 2003 01:16 AM

Jeff: If you can't find it, I'm not going to look for it. I already explained it. Talk to someone else who knows.

Note from forum administrator Chris Hurd: It is ALWAYS the responsibility of the person making the claim, and not the person reading the claim, to substantiate that claim with evidence. I am very suspicious of anyone who says "you go look for it" in response to a query asking for documentation supporting their claim. The responsibility lies with whoever makes the claim, and if they're unwilling to do the legwork to subtantiate it, then I doubt it's for real. -- CH

Frank: It appears that you don't have a clue what Andre is talking about.

Frank Granovski May 14th, 2003 01:26 AM

Joseph, I said you were wrong: a 3 CCD cam using pixel shift is still a 3 CCD cam, which captures superior/more accurate color than a 1 CCD cam. Since you said otherwise, the task is yours alone to prove.

Re: "...3-CCD camera; the way the CCD's are placed creates the same image as a 1-CCD camera with 3x the resolution of one of the chips." ---Jospeh George

Joseph George May 14th, 2003 03:17 AM

Frank Granovski: Joseph, I said you were wrong. A 3 CCD cam using pixel shift is still a 3 CCD cam, which captures superior/more accurate color than a 1 CCD cam. Since you said otherwise, the task is yours alone to prove.

Yes, you can call it a 3 CCD camera. It uses 3 CCDs, but the color, with the shift, will be same as on 1 CCD camera. The luma will have greater resolution, which will allow you to advertise it as a 2.4 megapixel digital still camera, but even that will not be 100% true, as the pixels will overlap and the image will be worse than from a true 2.4 megapixel camera, with the double No. of green pixels, etc.

Frank Granovski May 14th, 2003 03:41 AM

The you said I said response:

Re: "Anyway. Believe what you want. You obviously do not understand the technical issues...Enjoy your little toy."

No need to get defensive. I simply said that you are wrong.

Re: "If you believe that the camera has the same color as one that has the pixels properly aligned for the purpose of color improvement, fine.

That's what you think I said, but that is not what I said. This is what I said: "a 3 CCD cam using pixel shift is still a 3 CCD cam, which captures superior/more accurate color than a 1 CCD cam."

You said: "3-CCD camera; the way the CCD's are placed creates the same image as a 1-CCD camera with 3x the resolution of one of the chips."

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