View Full Version : Understanding CMOS Size


Anthony Meluso
December 30th, 2003, 12:01 AM
I have read many threads here and other places and have come to this conclusion that film like depth of field is not truly possible on a DV cam. I take pitures using film and know exactly how to achieve the right depth of field I want but to use these same princeables in the digital world is crazy. However film like depth of field can be achieved in photography on 6.5 and higher megapixal cameras. My question is why not take the CMOS size in digital photo camera and use them in video cameras. If I'm not mistaken I believe on a GL2 the pixel size is like 410,000 pixels. I know in the high end HDCAMs its about 2 megapixels. When do you think that film like depth of field will be aviable to DV CAMs.

Charles Papert
December 30th, 2003, 02:09 AM
Bigger sensor=bigger optical system=bigger bucks. How much is one willing to spend for a DV camera? Even the highest end Sony or Panasonic HD cameras still only use 2/3" sensors, just twice as big as an Xl1s but smaller than middle end digital still cameras.

Love to see it happen...don't expect it any time soon, unfortunately!

Oh, actually there is the "trick" answer to this...use a 35mm lens adaptor like the Mini35, or check out the homebuilt versions discussed on this board (Agus35).

Chris Hurd
December 30th, 2003, 02:19 AM
Howdy from Texas,

<< When do you think that film like depth of field will be aviable to DV CAMs >>

To echo what Charles just said, it's available *now* through the rental of the P+S Technik Mini35 image converter and 35mm motion picture lenses.

Also, high megapixel counts on CMOS or CCD sensors do not equal shallow depth of field... the physical size of the sensor will have more of a bearing than pixel count.

Large CMOS sensors currently will not generate 30 frames per second for video, nor would the 25mbps bandwidth of standard DV be enough to handle that amount of dataflow anyway.

Jeff Donald
December 30th, 2003, 06:18 AM
I don't think all the chip sizes, has ever been posted all in the same place.

1/7 inch (3.63mm), 2.3mm diagonal, 1.9x1.5mm (L x W)

1/6 inch (4.23mm), 2.7mm diagonal, 2.2x1.6mm (L x W)

1/5 inch (5.08mm), 3.2mm diagonal, 2.6x2.2mm (L x W)

1/4 inch (6.35mm), 4.0mm diagonal, 3.2x2.4mm (L x W)

1/3 inch (8.47mm), 6.0mm diagonal, 4.8x3.6mm (L x W)

1/2 inch (12.7mm), 8.0mm diagonal, 6.4x4.8mm (L x W)

2/3 inch (16.9mm), 11.0mm diagonal, 8.8x6.6mm (L x W)

1 inch (25.4mm), 16mm diagonal, 12.8x9.6mm (L x W)

These are actual chip sizes and effective sizes are slightly smaller.

Filip Kovcin
December 30th, 2003, 09:50 AM
hello there,

maybe this link is usefull - it looks for me that almost all sizes are included (film, photo and video)

http://www.panavision.co.nz/main/kbase/reference/tbleframelist.asp