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#1 Daniel Madsen

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Posted 05 February 2007 - 03:36 PM

what are the circle of confusions for 1/4, 1/3, 1/2in CCDs?


hope someone has an answer
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#2 K Borowski

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Posted 05 February 2007 - 03:41 PM

Well, it depends on your acceptable sharpness, intended viewing size, and the lens you are using. There's a mathematical formula I have in an old Naval Photography guide at home somewhere. If you give me the area of each of those sensors, I could probably figure it out using the formula.

As a rule, the smaller the chip, the greater the depth of field, and the greater amount of leeway you have with focus.

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#3 Daniel Christie

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Posted 10 February 2007 - 10:31 PM

The CCD size is not actually representative of the image size. There was a discussion of this in another forum awhile back... I'll see if I can find it.

Daniel
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#4 Chris Keth

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Posted 12 February 2007 - 12:00 AM

For chip sizes, figure out the actual size of a pixel on the chip. That should be your CoC since anything smaller will just be represented by that pixel. Perhaps go with 1/2 the pixel size to be safe.
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#5 George White

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Posted 12 February 2007 - 12:13 AM

For chip sizes, figure out the actual size of a pixel on the chip. That should be your CoC since anything smaller will just be represented by that pixel. Perhaps go with 1/2 the pixel size to be safe.


I think its more (and and also less) complicated than that. There is a huge amount of information about depth of field on the net. I found this article http://www.bealecorn...trv900/dof.html that specifically addresses it for various size video sensors. I'm sure with a little digging you can find a better site and all the information on the topic you'd like.

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#6 Will Earl

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Posted 12 February 2007 - 02:16 AM

Panavision has the CoC ranging from 0.008mm (1/4") to 0.021mm (2/3") for the CCD sizes you mentioned.

http://www.panavisio...calcFOVform.asp

Unsure how accurate it is through. Probably a decent starting point.
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#7 Chris Keth

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Posted 12 February 2007 - 11:03 AM

I think its more (and and also less) complicated than that. There is a huge amount of information about depth of field on the net. I found this article http://www.bealecorn...trv900/dof.html that specifically addresses it for various size video sensors. I'm sure with a little digging you can find a better site and all the information on the topic you'd like.

---george


I realize that is a very unscientific way to look at it but it will probably estimate your actual visual depth of field better than any of the formulas based on chip size and viewing size. Those will tend to underestimate the depth of field since they are for sensors of unlimited resolving power (i.e. they don't take resolving power into account)

Compare 16mm film and an equivalent size SD chip. They will have the same calculated DoF but very different visually apparent DoF since the chip's ability to render fine changes in focus is so limited.
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#8 Leo Anthony Vale

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Posted 15 February 2007 - 12:11 PM

Panavision has the CoC ranging from 0.008mm (1/4") to 0.021mm (2/3") for the CCD sizes you mentioned.

http://www.panavisio...calcFOVform.asp

Unsure how accurate it is through. Probably a decent starting point.


Circle of Confusion is an arbitrary number based partially on how large the imaged will be magnifyed.

http://en.wikipedia....le_of_confusion

http://www.nikonlink...unklbil/dof.htm
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