Digital Camcorder CCD

[brandon184]

I keep seeing a certain number of megapixels associated with the CCD of a digital camcorder. How many megapixels would a studio/production-quality CCD have?

Thanks.

[Brian Ellis]

3 x 1/2 Mpixel would suffice to obtain broadcast quality for standard NTSC or PAL with no compression. However, camcorders often have more for stills, and remember that the inbuilt compression and low-cost electronics will limit the bandwidth to less than that quality. If you are not using the camcorder for stills, then 3 x 350,000 will be sufficient, especially as the average camcorder lens is usually like the bottom of a Coca-Cola bottle.

[Dr Mordrid]

DV cameras use the same frame size regardless of how many megapixels the CCD contains (NTSC: 720x480/345,600 pixels; PAL: 720x576/414,720 pixels).

Most consumer cams use a single CCD for the entire scene while a 3 CCD cam (an upper model feature) uses one for each primary color to improve color quality, but the final frame size is the same in both types.

All a CCD size over and above the standard DV frame affects is the resolution of the stills you shoot and, in some cameras, how wide a range of movement can be handled by the cams electronic image stabilization. If the camera uses optical image stabilization then it only helps with the stills.

Pro HDTV digital cams used by studios (mainly Sony's HDCAM) use a frame size of 1920x1080 (2,073,600 pixels).

Dr. Mordrid

[brandon184]

What digital camcorder(s) would you guys reccomend for broadcast-quality shooting?

The camera would not be used for stills. It would be used for both indoor and outdoor shooting.

Strong color and clarity definition are important.

~ Brandon

[Dr Mordrid]

I like Panasonic camcorders;

AJ-SDX-900 (3 CCD: $25,000 list)

http://www.panasonic.com/PBDS/subcat/Products/cams_ccorders/f_AJ-SDX900.html

Panasonic DVX-100 (3 CCD: $3,795 list)

http://www.panasonic.com/PBDS/subcat/Products/cams_ccorders/f_ag-dvx100.html

AG-DVC80 (3 CCD: $3,295)

http://www.panasonic.com/PBDS/subcat/Products/cams_ccorders/f_ag-dvc80.html

AG-DVC7 (single CCD: $1,295)

http://www.panasonic.com/PBDS/subcat/Products/cams_ccorders/f_ag-dvc7.html

Dr. Mordrid

[brandon184]

Excuse the stupidity/ignorance... But I don't understand what you mean when you refer to single CCD compared to 3 CCD, etc. Which is better? What would broadcast-quality have?

Thanks!

[Dr Mordrid]

A broadcast cam would have 3 CCD's.

After the light exits the back of the lens there is a prism that splits the scenes light into 3 parts with each containing one of the lights primary colors; red, green or blue (RGB). Each primary color gets its own CCD tuned to getting the highest qualty out of each. The info from all 3 CCD's is enhanced and recombined electronically before it's encoded to DV and laid down on tape.

In a single CCD cam one does all the work, but not quite as well.

Here's some reading for you;

http://www.internetcampus.com/tvp015.htm

Dr. Mordrid

[brandon184]

Cool. Thanks for the info!

[brandon184]

New question - what does that $25,000 camera have that seperate it from the other 3 CCD cameras you listed?

[Dr Mordrid]

More/better features; higher quality filtration, the choice of 24p (film speed), 30p or 60i, a better digital signal processor, the ability to switch between the DVCPRO and DVCPRO50 formats etc.

DVCPRO50 uses twice the bitrate of miniDV and DVCPRO (50 mbps vs. 25 mbps) and offers a 4:2:2 colorspace for better compositing and effects (bluescreening etc.). NTSC miniDV and DVCPRO both use a 4:1:1 colorspace (miniDV PAL = 4:2:0), which can cause problems when doing effects...particularly keys and overlays. The higher bitrate and colorspace of DVCPRO50 will also minimize artifacting with multiple generations of recompression.

The difference between miniDV and DVCPRO? DVCPRO uses larger tapes, which allow up to 123 minutes vs. 60 minutes for miniDV.

Another biggie would be an anamorphic 16:9 mode (horizontally squeezed to fit a 4:3 frame) instead of a plain letterboxed 16:9. Anamorphic 16:9 gives a better result than letterboxing but not as good as an HDCAM's 1920x1080, but then HDCAM's start out at $65,000 USD

Dr. Mordrid

[Brian Ellis]

Whereas I agree with what Doc has written, you may also wish to consider DVCAM, which is a better quality of DV recording developed by Sony. This is used in their pro and some semi-pro cams. They can accept full DV size and mini-DV-size tapes, but you lose 33% of the tape capacity (i.e., a 1 hour mini-DV lasts only 40 minutes and a 2 hour DV 80 minutes). You can play a recorded mini-DV tape in a DVCAM device but NOT vice versa.

Much of the difference between pro cameras and 3-CCD pro-sumer ones (<~$3,500) is in the optics. A good lens costs at least a couple of thousand, alone. Some of the cheaper 3-CCD cameras (which I recommend) do not have prisms but use half silvered dichroic mirrors, which are less good. (Prisms are comparatively heavy!)

[KRSESQ]

Doc:

I assume the Panasonic AG-DVC7 only handles 720x480, 60i? Not 16:9 resolution?

Or does the viewfinder include 16:9 framing guides (for cropping to 16:9 letterbox in post)?

That is one very attractive looking camera.

Kevin

[Dr Mordrid]

24p = 24 fps progressive (no fields; each frame is a bitmap)

30p = 30 fps progressive (no fields; each frame is a bitmap)

60i = 60 interlaced fields (the 30 fps you're used to seeing)

24p is becoming a big deal because it not only is the same frame rate as film, which gives you a "film look" without processing, but it also is DVD legal...which means you can encode more bits/frame for better visual quality while getting a smallish file size. The player itself does the conversion to TV-legal frame rates.

Even DV cameras that support 16:9 shoot it at 720x480/576, regardless of if they're anamorphic or letterboxed.

In anamorphic 16:9 the widescreen video gets horizontally squished to fit the 4:3 aspect ratio, something like you see in SVCD. Though this seems to be a major quality loss it isn't given that in a 720 wide DV frame there are only 180 color samples spread across 4 pixels each.

This movie sites anamorhpic info page (both Cinemascope and Panavision being anamorphic movie formats) should give you an idea of what happens;

http://home.hiwaay.net/~criswell/theatre/static_subpages/formats/anamorphic_format.html

The other 16:9 method is letterboxing, which is used in cheaper cameras. It's weakness is that it fakes a 16x9 aspect ratio by overlaying black bars on the standard 720x480/576 high DV frame. Not exactly impressive IMHO.

Between you, me and the wall I'd rather get a GOOD anamorphic lens attachment for a 4:3-only DV cam than put up with letterboxing. An anamorphic attachment does the horizontal squeeze optically as was done with Cinemascope and Panavision in movie film cams, but a quality one isn't exactly cheap running $500-700 USD.

DV cams won't get full widescreen without such tricks until they start using the HDTV frame sized of 1920x1080 or some other 16:9'ish resolution with a width evenly divisible by 16 (to make it MPEG legal).

Dr. Mordrid

[smitty]

I think Brian has hit the mark. Given appropriate lighting ,the quality of the lense plays a major role in the resulting video.
No one has mentioned the Canon XL1-s.
(3 ccd , interchangable lenses, optic image stabilizer)
I find it to have an excellent lense and the resulting video to be broadcast capable .
I see Brandon you are from Canada.The XL1-S is about $6000 Canadian.
smitty

[Hulk]

Very interesting discussion.

A couple questions.

1. Do the following 3CCD cams use dichroic mirrors or prisms, TRV950, GL2, XL1s, DVC80.

2. If the CCD diameter were equal for a 1CCD and 3CCD camera, would not the 1CCD camera have better lowlight capability, theoretically? Since there will be photonic absorption losses during the refracting of the light? A good example would be low light capability of Optura Pi vs GL2.

- Mark