View Full Version : Size of CCD chips
Clint Grant June 27th, 2005, 12:17 PM Hello everybody. I have another basic, terribly newbie question, but I have to know. What difference does the size of CCD chips have on a camera? For example, a Canon Xl1s has 1/3 size chips, while GL2 has 1/4 size chips (I think). This difference causes some people to buy the XL1s over the GL2. Thanks for any help, Clint Grant
Matt Irwin June 27th, 2005, 02:18 PM A larger chip (usually) means higher capture resolution-- there is more "real estate" to fit pixels into (don't confuse caprture res with image resolution: all SD video from miniDV to DVCPro50 to DigiBeta is 720x480). Larger chips also have a shorter depth of field which is associated with a "filmic" look if utilized.
Professional camcorders usually have 1/2" or 2/3" chips, as well as a better and wider selection of lenses. The XL cameras are also attractive to many for their ability to use a wide variety of lenses via an adaptor, among other reasons.
Hope this helps.
Joshua Provost June 27th, 2005, 02:19 PM Bigger chip generally means better low-light performance (of course that is assuming the same number of pixels, but a larger chip).
Clint Grant June 27th, 2005, 05:32 PM Thanks to you both for confirming that for me. I was just unclear on the logic of the chip size. Thanks agin, Clint Grant
Chris Hurd June 27th, 2005, 06:01 PM Larger chips also have a shorter depth of fieldWoah, hold on there... image sensors have no "depth of field" at all. Depth of field (DoF) is an optical property of a lens. There is no direct relationship between CCD size and DoF... only an indirect relationship. See this link for more info about DoF:
http://www.dvinfo.net/articles/optics/dofskinny.php
Matt Irwin June 27th, 2005, 06:52 PM Woah, hold on there... image sensors have no "depth of field" at all. Depth of field (DoF) is an optical property of a lens. There is no direct relationship between CCD size and DoF... only an indirect relationship. See this link for more info about DoF:
http://www.dvinfo.net/articles/optics/dofskinny.php
I know. I worded that poorly, probably in an attempt to be concise. oops. heh.
Thanks for keeping me in check, Chris.
Laurence Kingston July 2nd, 2005, 10:12 AM I always thought larger CCDs meant shorter depth of field too, and I know I've seen it in print many times. None the less i realize you are right. It's just that camcorders with bigger CCDs tend to allow shorter depth of field f-stop settings because they need less light. In actual practice this means you can usually get shorter depth of field with a larger CCD camera.
Ash Greyson July 2nd, 2005, 11:43 AM The technical jargon doesnt really matter... a 2/3" CCD camera has a better DOF than smaller chip cameras. As mentioned above, just the fact that it allows more light in, allows for a better DOF, even if similar lenses were used...
ash =o)
Andre De Clercq July 2nd, 2005, 12:17 PM For the same f-number and the same subject size, the larger the sensor (CCD) is, the lower the Dof
Chris Hurd July 2nd, 2005, 12:21 PM a better DOFOops... Ash... be careful how you describe that. "Better" is a relative term. For some folks, "better" will mean a deep focal plane (like Citizen Kane), and for others it will mean a shallow focal plane. Around here it's much more helpful to describe things in absolutes rather than superlatives -- thanks,
Joshua Provost July 2nd, 2005, 01:32 PM Yes, bigger means shallower. 1/3" about the same as 8mm film; 2/3" like 16mm. You'd need about 1 1/3" to equal the shallow depth of field of 35mm film.
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