Digital Camcorder CCD

[Dr Mordrid]

1. All of those cameras use prisms.

2. Don't forget the huge influence of the LENS. You could have the most sensitive CCD around but with a lens that can't open up enough to take advantage of it low light will give you fits. Also note that CCD's in camcorders can be 1/4", 1/3", 1/2" or 2/3".

That said, of the cams you listed here are the CCD sizes:

TRV950 - 3x 1/4.7" (Yup...that's what Sony says)

GL2 = 3x 1/4"

XL1s = 3x 1/3"

DVC80 = 3x 1/3"

Optura = 1x 1/4"

The JVC GY-DV550U is an example of a pro cam with 3x 1/2" CCD's. ~$7,000 USD.

The JVC GY-DV700WU is an example of a pro cam with 3x 2/3" CCD's that are 16:9 in aspect ratio. ~$9,000 USD.

Dr. Mordrid

[smitty]

1 . the xl1-s and the gl2 use prisms

2. I think there are a few other facts involved
eg. assume say a 1/3" ccd depending on a/ the number of pixels in the sensor and b/ the actual size of each pixel the quantity of light could be higher with larger pixel size

Also I think the electronics( quality of ) and how well adjusted they are play a role in low light ability.
Black level , white balance , PPV , etc.
Also there is somewhat of a tradeoff in low light quality versus quantity. To each his own.
I'll take 3ccd's everytime.
smitty

[Brian Ellis]

There are several factors involved in low-light sensitivity. The most important is the capacitance of the pixel of a CCD. This depends on the area of the pixel, the thickness of the dielectric and the dielectric constant. As the dielectric material and therefore constant is always similar, only the thickness and size can have an influence on the capacitance. Then there is the light-sensitive semiconductor materials and the form of the junction.

It is therefore not possible to say that a given size has a given light sensitivity, as the signal:noise ratio (which the electronics will also play a role in) is also a determination.

I have a Panasonic NV-DX1 which has 3 CCDs of 380 kpixels each. I have a friend with the NV-DX110, with the same spec. Mine is ~3 whole stops more sensitive than his and gives a better image. That means that his kicks in the extra gain in poor light conditions than does mine, so I also have a better s/n ratio. In their still cameras, Fujifilm make a great commercial ploy of their interlocked hexagonal pixels, which are larger than the traditional square pixels and therefore have a better sensitivity, all other things being equal.

[Flying dutchman]

@DocMordrid:

I'd like to add the remark that 24p is fairly easily converted to PAL framerate with little quality loss.

How about those new three-layered CCD's we read about some time ago, the ones that are supposed to make 3-ccd camcorders look old? Any good cameras made with those?

[Dr Mordrid]

There were a couple of these in the works. One was a new multi-layered CCD by Canon and the other the Foveon X3.

I haven't seen much lately about Canons multi-layered CCD.

Not much was going on with Foveon until Sigma came out with an SLR using it; a turkey at that, but not because of the CCD.

Another recent bit of Foveon news came this last March when National Semiconductor licensed the X3 technology, so there may yet be hope for it.

Dr. Mordrid

[Brian Ellis]

I wouldn't invest too heavily in it for hi-quality work at this time: there are still many technical ifs and buts.

[Dr Mordrid]

Exactly why it's not in the video market already. Nobodys going to commit to it 'til all those questions are answered.

Dr. Mordrid