1ccd vs 3ccd
 

hi everyone im new here

besides low light is their a huge diffrence between 1ccd and 3ccd.can someone tell the diffrence between the hv10 footage and the xh-a1 in default setting,daylight recording.thank you

The difference between single-chip and three-chip camcorders lies mainly in how they reproduce color.

Keep in mind that the image sensor is a monochromatic device and doesn't know what "color" is. Therefore it needs a color filter. There are two kinds of single-chip camcorders... those with complimentary (CMY) color filters and those with primary (RGB) color filters. If the camcorder has an RGB color filter, then it will build color information the same way that a three-chip camcorder does, through the Red, Green and Blue color wavelengths. So the answer to your question is yes, *if* the single-chip camcorder has an RGB color filter. The Canon HV10 and HV20 have these primary color filters.

See http://www.dvinfo.net/canonoptura/ar...ra70-2.php#rgb for a little more info.

I've been impressed by the HV10 in good contrasty outdoor light (magic light) not only in resolution but color reproduction when compared to my HVX200. It doesn't have the dynamic range in the shadow detail but it's pretty amazing for what it is. After pushing the levels a little it intercuts in fairly well.

One thing to keep in mind is that a lot of the 1 chip camcorders that you see aren’t CCD but are CMOS based. CMOS are much cheaper but the color reproduction is much better which is why CMOS camcorders look just as good as 3 CCD camcorders.

And another thing to keep in mind is the digital still camera industry... all digicams from point & shoots to Digital SLRs are single-chip RGB. It won't be too long from now (hopefully) when the video camera industry will follow suit.

Hadn't thought about the still camera comparison... Not sure I agree that single chip is as good as 3 chip - I can't think of any pro camcorder that is single chip?

That said, if they do develop single chip to the same quality as 3, it should bring the cost down a bit!! Somehow, I can't see Sony et al doing that!!

All the best

Besides the Sony A1u, this:
http://dvinfo.net/conf/showthread.php?t=85486
And lest not forget about the RED, because if I remember correctly, it’s going to use only 1 CMOS imager which is one of the reasons its going to be very affordable for what it can do.

....so many questions now...

isn't the big advantage of 3CCD that color resolution is 3 times as high?

- Or does the color separation process by prisma introduce a loss?
- Or is CCD a more noise-prone technology than CMOS?
- Or does YUV depth compression result in enough loss to diminish the 3CCD gain?
- Or do CMOS sensors generally have higher pixel values thus compensating for the color-res loss?

I'm not asking for an 'encyclopedia' (in fact the theory can be found on the web of course), but If you have any thoughts on this...

(and we may want to move this :)

In many ways 3CCD is kind of a waste for most shooting. any extra color detail that may be there is instantly lost when compressed to 4:2:0. Even if you did a live capture as 4:2:2 you still loose half the chroma pixels anyway.

1 chip cameras can have interpolated pixels because every other pixel needs to be calculated. For example "GRG" The green pixel where the red pixel is needs to be interpolated to fill it in. This is done by math formulas. 3 chip cameras have the advantage of having every pixel there but "only" if they use the native resolution to begin with. A HD camera that uses for example 3 960x540 pixel chips and uses pixel shift to get to 1920x1080 also uses interpolation. Pixel shift is much better then just normal resizing but it still has pixel blanks that need to be filled. That is why I think a 960x540 3 chip camera is pretty much just as good as a 1920x1080 single chip camera. In fact I think the single chip is better because you still have an accurate 1920x1080 array and only in between pixels need to be calculated. At least one color is accurate for every pixel in the array. Pixel shift kind of depends on certain colors in the scene. If you have a scene with a lot of reds and blues and very little green then the pixel shift will not help as much. This is because the green chip is offset by half a pixel but if the colors do not really contain any green component then it doesn't see it anyways.

Again if you are shooting to tape or pretty much any camera based format you have reduced color anyways so the only time any of us would see the loss of color is if you could somehow yank RGB frames from the camera which none of us can do.

This is why the only HDV/DVCPROHD camera that offers you a true 1x1 pixel representation is the JVC HD100/HD200 series of cameras. But if you record to tape or even uncompressed it doesn't really matter because you loose 1/2 or 3/4 of the color anyways.

thanks for the replys,i read somewhere that the hv10 can get better picture than fx1,what do you guys think.

Absolutely! It can get better images than my A1 in good light. But it depends on the shooting scenario.

The HV10 is killer!

but are the color accurate as the a1

Colors can be very accurate with a single chip camera. I mean the RGB filter in front of the chip passes RGB colors to the DSP. A 3 chip camera uses a prism to split the light into RGB and each chip reads that RGB from each slpit beam of light. In the end it is all reading as RGB. The only difference is that 1 chip cameras have to interpolate every other pixel for each channel. The colors are very accurate, the image just isn't as crisp as it could be due to the interpolated pixels. Remember extreme highend DSLR's are also using a RGB filter with a single chip and these produce images that are very photographic for even some of the most strict pros. Even the interpolated pixels can be accurate because they are based on formulas used from the other pixels in that area.

Canon is well known to create some very accurate colors with it's DSLR cameras using a RGB filter so it is safe to say they kind of know what they are doing.

how is the hv10 in low light

very interesting discussion =D.

lemme add to the questions:
1. what's this business with chroma? what is it such a difficult thing to both capture and reproduce in general?

2. been reading about industry moving towards 36-bit color (cause HDMI1.3 standards, new LED/technology displays coming out). what will this mean for recording?

This all stems from the fact that CCDs and CMOS are not colour sensitive. Therefore, in order to define the colour coming out of a CCD/CMOS pixel, you have to know before hand what colours it can see.

If you use a 3-chip setup (which can be done for both technologies) you split the light into red, green and blue, and you have a whole CCD for each colour. You use some patterned filter (Bayer, etc.) on a 1-chip design.

The problem is, when the information is stored to disk or tape, it is compressed. The easiest way to compress something is to simply throw away the information... so that's what they do. The whole YUV scheme says that you calculate the luminosity (how bright) each pixel is in the image and you store that in a grid. You then do two additional calculations to produce 2 chroma channels, which can be used to re-construct the colour. Up to this point the procedure can be pretty much lossless.

But then people say that they are more sensitive to brightness than they are to colour (we have both brightness and colour sensors in our eyes. In general, we have more brightness ones)... so they reduce the resolution of the chroma channels by a factor of 2 (4:2:2) or a factor of 4 (4:1:1 and 4:2:0). Specifically they reduce the information in the horizontal dimension. The claim is that we are less sensitive to horizontal things than vertical things, but I expect it has more to do with the horizontal scanning nature of CRTs.

If you ever have the chance to look at some truly uncompressed 4:4:4 video, you'll be amazed at how bad chroma compression really is.

-Steve

color bits are how many different colors there can be in each RGB channel. For example 8 bit color has 256 shades per channel. There are 3 channels of color to equal 24bit. 36bit means 12bits of color per channel. That means each channel can have 4096 shades per channel instead of just 256. This can reduce color banding in color gradients. Spreading 256 shades of blue across a 1920x1080 pixel image can cause color banding because the color gets spread in chunks because there are not anough samples to soread throughout the whole image. With 4096 samples there are more then enough samples per channel to fit the 1920x1080 image.

This has nothing to do with chroma compression however. A 36bit image can still be compressed as 4:2:0. What this means is that each color has a wider range of possible colors but the detail is still reduced.

The only chance any of us ever have of being able to shoot 36bit color is with some form of mpeg4. Mpeg2 cannot use anything other then 8 bit color so no HDV camera will ever have 36bit color.

Isn't the potential limiting factor on the HV20 (vis a vis three chip camcorders or pro-single chip) the size of the chip itself? I'm sure the images are great in good light but isn't noise a real issue esp. in low light on smaller chips? The other thing is the unlimited DOF you get from such a small chip. It's very difficult to throw the background out of focus. Whereas a single full size (35mm) chip gives you a chance to get a very narrow DOF. But single 35mm-size HD-rez chips are still very expensive to manufacture and also require lots of bandwidth in camera to process. So as an aspiring filmmaker, the large DOF on an HV20 would be my biggest hesitation.

Well now that is what makes this a consumer camera. It isn't designed for professionals. It can be used and give very pro results but it isn't meant for that.

We must remember this is a consumer camera. It is what it is and we should not expect it to be a pro camera. If you want a pro camera you should get a pro camera. If you are concerend about DOF even a 1/3" pro camera can be hard to work with. That is why there is all talk of 35mm adapters for cameras. Even a $9,000.00 XLH1 has DOF field issues. A 1/2.7" chip is actually a tiny bit larger then a 1/3" pro chip so at least the HV20 is starting to move in a better direction.

Sorry if I was stating the obvious :-( but it seemed like low light noise and DOF were bigger issues than how a single chip handles colorspace.

It all depends on the person. While lowlight noise may be a concern for some people, it is something that can be overcome by using lights. Color space however is something we have no control over. DOF is also something that not everybody is going to be concerned about. A consumer will want the opposite effects of DOF then what a filmmaker would want. For DOF it is another one of those things that is subjective and can be worked on by the user if they so choose. A 35mm adapter can be used if you must have a certain style of DOF. Color space and overall quality from the camera, chip and DSP is something that none of us have control over so it is nice to find a camera that works for us.

Besides the HV20 should be better at DOF then any other 1/3" camera since it has a 1/2.7" chip. This is the first camera other then 1/2" or 2/3" cameras to have a chip larger then 1/3". I know it isn't that much larger but it is a step in the right direction. You will get the same type of results for DOF as you would with any highend 1/3" camera and maybe even slightly better. As far as I know this is the only HD camera under roughly $25,000.00 that has a chip larger then 1/3".

Just to clarify -- it is the first HD camera other then 1/2" or 2/3" cameras to have a chip larger then 1/3". It's been done before in standard definition (re: the last models from the Canon Optura series DV camcorders).

wow thanks for the easy to understand answers!!! as usual, this place rocks. thanks thomas&steven.

ya'll really are "experts" when it comes to this stuff.

In milimetres (diagonal), how large is the surface area of 1/3 and 1/2.7"? How much larger is the HV20's sensor.

In all actuallity it is easier than it looks, although I am not sure who decied to do a decimal fraction to represent size, but a 1/3ccd is .33 inches (although most ccds can be misrepresented by size) and the 1/2.7 Cmos sensor is .37 inches.

A pet peeve of mine... don't get me started.

I wrote a little bit about it here: http://www.dvinfo.net/canonoptura/ar...eage.php#opccd

The interesting thing about the HV10 is that it actually has LESS noise in reasonable to good light than many prosumer cams costing much more. The pristinity of its image is one of the great things about the HV10.

im going to be making a lot of short films,some event videography,will the hv20 be good enough or should i step up to the a1.thank you

I'm coming from a DVX100 (original) and am chomping at the bit to replace it. I do my creative stuff (short film projects, etc.) with it but also a lot of family video and some weddings. That latter two tend to be low light stuff (I usually light my film projects). The XH A1 is my first choice for a new video camera but I'm also going to replace my Canon Rebel XT DSLR this year with a higher end (hopefully full frame) camera. So to buy both a Canon 5D (or it's replacement) and the A1 means a bit of a hit financially ($6-7K). Now all of a sudden the HV20 looks like an appealing (i.e., low cost) HDV solution. I can't wait to see the image it produces.

Keep in mind that the HV10 is still not a stellar performer in low-light. HDV cams in general need plenty of light. With that said, cams such as the A1 or Sony FX7/V1/FX1 are still better in low-light than the HV10. But give the HV10 decent light, and you'll be hard pressed to tell it apart from far more expensive HDV cams.

so you think the color color accuracy is the same as the fx1 or even better.

I think it's pretty close. Without an A/B test, you'd be very hard pressed to tell any significant differences. The CMOS sensor starts off with better color rendition than a CCD, but the other cams have 3CCDs which evens the playing field. But I can tell you with the HV10 that I've never seen better color rendition from any single sensor camcorder.

does anyone have a side by side test of the hv10 and a1,or some still grabs of the hv10 footage in daylight.thanks for all the replys.

Comparison between HV10, FX1 and XDCAM

http://www.dvinfo.net/conf/showthread.php?t=81364

Patrick

Exciting discussion!