EX1 sensor dimensions?

Vince Gaffney · December 5th, 2007, 04:41 PM

And here's the CMOS version from silicon imaging. it's near the bottom

http://www.siliconimaging.com/ARTICL...#cmosimgerchar

vince
or just go here and look at the sizes

http://www.dvinfo.net/conf/attachmen...3&d=1196679037

Noah Yuan-Vogel · December 5th, 2007, 04:55 PM

perhaps this is of some help:

http://www.dpreview.com/news/0210/02...ensorsizes.asp
http://www.panavision.co.nz/main/kba...eframelist.asp

unfortunately, these are not always consistent between cameras... notice that at 2/3" on the panavision site there are several listings for different dimensions. there is no listing for 1/2" 16:9 so its hard to say if the ex1's 16:9 adopts the 4:3 1/2" specification's height or width or diagonal.

according to that chart, 16m film actually has a diagonal of about 11mm, 1/2" cmos about 8mm, and 8mm film about 6mm

so 1/2" is somewhere in between standard 8 and 16mm film

Noah Yuan-Vogel · December 5th, 2007, 05:05 PM

who knows, maybe the vignetting issue some people have is because sony went with a 16:9 1/2" sensor that is 8.5x4.8mm, but the lens is intended for 4:3 1/2" sensors and they were too generous with how they came about 16:9 from the normal 1/2" sensor format. totally pulling that out of thin air but that would explain some things.

Carlos Moreira · December 5th, 2007, 05:10 PM

yes. this might be the explanation - its set too close. If you resize the sensor vertical from 16:9 to 4:3 you get a higher diagonal value.
Tis also explains the good DOF. calculated in 4:3 the sensor may be just a bit smaller then 2/3.

could somebody please cut off the glass to have a look ? ;-)

Brian Drysdale · December 5th, 2007, 05:39 PM

No HD camera is 4 x 3, they're all widescreen format.

Noah Yuan-Vogel · December 5th, 2007, 05:53 PM

right, although its not unheard of for a camera to have a 4:3 sensor and crop to 16:9. the canon hv20 does this with its 1/2.7" sensor. i was just suggesting the ex1 might do the opposite by expanding horizontally instead of cropping vertically. there does not seem to be that much information on sensors that are 1/2" and 16:9. perhaps we might learn more if we look at sony's other 1/2" xdcams. there are plenty of machine vision 1/2" cameras that are HD-like resolution but most of them are 4:3.

Carlos Moreira · December 5th, 2007, 05:55 PM

this not an issue of HD or not but a simple question of sensor dimensions.
You can also use a 4:3 sensor and crop it to get 16:9

popular example is the XL2. it has 1/3 4:3 sensors which are cropped for 16:9. the result is a smaller real size and really bad DOF.

Eric Pascarelli · December 6th, 2007, 12:15 AM

I've never seen the actual spec, but my best guess is that the active area of the imager is 7.2mm wide x 4.05mm high.

The first reason that I think this is the measurement is because 2/3" HD cameras are widely known to be 9.6mm x 5.4mm.

2/3" times .75 = 1/2" and so multiplying the 2/3" chip dimensions by .75 gives me the above figures (of course I know that chip sizes are based on old vidicon tube dimensions and hence are not so neatly proportional as this).

The second reason is from measuring the field of view and distance with a tape measure.

At full wide, 5.8mm, I measured the distance to a wall, and the distance between two tape marks on the wall placed at the left and right edges of frame. This gave me enough information to calculate the chip size, assuming two things - that the lens focal length is really 5.8mm and that the EX1's monitor shows the whole frame with no cropping (in fact it does not, but it comes close). From these measurements I estimated 6.54mm width.

I did the same thing at full tele, 81.2mm. The number I got was 7.75mm, with the same two assumptions.

The dimensions 7.2 x 4.05 fall neatly between these two estimates.

It's clear to me that the actual lens focal lengths on the EX1 are a bit different from the lens markings. I don't believe the lens goes quite as wide or as long as its markings indicate, but that's for another thread, and I can certainly measure that definitively once I find out the size the 1/2" HD chip.

If someone finds the actual dimensions of the active area of the EX1 chips, please let me know.

Chris Hurd · December 6th, 2007, 12:50 AM

Quote:

Originally Posted by Bill Spence

I read somewhere on these boards (I think it was Barry Green), that the sensor size is actually quite a bit smaller than the actual chip.

You've read it on these boards from both Barry Green (at least once) as well as myself (several times).

Barry touches on it here:

http://www.dvinfo.net/conf/showpost....6&postcount=21

Two weeks earlier, I had mentioned it here:

http://www.dvinfo.net/conf/showpost....1&postcount=20

Plus, both of those occasions were in this particular forum.

Quote:

Originally Posted by Carlos Moreira

...the result is a smaller real size and really bad DOF.

There is no such thing as "bad" DOF (depth of field). There is only shallow DOF or deep DOF or points in between, but you cannot possibly characterize deep DOF as being a "bad" or undesirable quality. There will be circumstances in which a person may want shallow focus and there will be other circumstances in which a person may want deep focus... one is not better or worse than the other; it's simply an aesthetic choice.

Keep in mind that one of the classics of American cinema, Orson Welles' 1941 masterpiece "Citizen Kane," was mostly composed of shots using very deep focus, that is, copious amounts of DOF, to the extent where they had to resort to composites for some scenes because the lenses they were using couldn't present the extremely broad depth of field they wanted.

Hand me a cheap consumer camcorder with a tiny 1/6th-inch chip, and I'll show you how to produce a very shallow DOF with it. See http://www.dvinfo.net/articles/optics/dofskinny.php for more info. There is no such thing as "bad" DOF.

Eric Pascarelli · December 6th, 2007, 01:27 AM

To further that point, Chris, I would suggest that if there were in fact a "bad" depth of field, it would be shallow DoF and not the deep DoF of these small format cameras.

In 35mm film production, much effort and money is expended to get "enough stop" to hold focus for a particular scene - to hold focus between an actor's eyes and nose for example. This can mean doubling the amount of lighting equipment, pushing the film or whatever. In so many cases in the past (another example is miniature photography) I would have loved to have been able to use one of these miraculous cameras with which everything is in focus!

Over the past decade, with the rise of small format digital acquisition and post, shallow DoF has become a sought after effect and not simply a byproduct of the medium. This is is exemplified when I work with CG artists who might ask me "do you want me to add more depth of field to that?" And I say "no - there's already too much - make the the background softer"

Our definitions of DoF are opposite - to me, more depth of field means deeper depth of field. To them it means shallower DoF, because in their world, everything is in focus, and "depth of field" is a filter that's added in post.

35mm adapters are lovely, but at times I think that they are superfluous added "effect" - a shortcut to an appearance of quality at the expense of other qualities. There are plenty of ways to tell a great story while embracing the small format medium and its wonderful deep DoF.

Chris Hurd · December 6th, 2007, 01:39 AM

Quote:

Originally Posted by Eric Pascarelli

...I work with CG artists who might ask me "do you want me to add more depth of field to that?" And I say "no - there's already too much - make the the background softer"

Our definitions of DoF are opposite - to me, more depth of field means deeper depth of field. To them it means shallower DoF, because in their world, everything is in focus, and "depth of field" is a filter that's added in post.

Let me assure you then...

On *this* site, CG artists are no, "more depth of field" definitely means deeper depth of field. If I have to drive to somebody's house with my twenty-year-old copy of Citizen Kane on VHS and whack them over the head with it, "more DOF" equals a deep focal plane.

"Bad DOF" is what my Rottweiler is when I come home from the dentist.

Carlos Moreira · December 6th, 2007, 03:30 AM

when the DOP / director WANTS or NEEDS the DOF to bee deep it is a free artists decision. But if he wants to have a shallow DOF and can´t archive it due to technical limits of the camera, it´s simply bad.
And of course I always can get a (more) shallow DOF when using tele, but this also means a very long distance from camera to object and no chance to get shallow DOF on in-room shots.
Even the EX-1 has a bad DOF for me, but it touches the lower range of what is useful.
For me the DOF of the EX-1 looks close to 16mm.

Brian Drysdale · December 6th, 2007, 09:04 AM

Quote:

Originally Posted by Carlos Moreira

You can also use a 4:3 sensor and crop it to get 16:9.

Any HD camera I've used that offered 4x3 cropped either end of the 16 x 9 image, rather than cropping a 4x3 top and bottom to create 16 x 9. This was for shooting DV.

Chris Hurd · December 6th, 2007, 09:39 AM

That's true Brian, but the post by Carlos that you're referring to:

http://www.dvinfo.net/conf/showpost....6&postcount=22

...makes it clear that he was speaking about the standard definition Canon XL2.

And he's right, it's certainly possible to use a 4:3 sensor and crop it to get 16:9, which Canon did with the XL2, as I've explained here: http://www.dvinfo.net/canonxl2/articles/article06.php

Brian Drysdale · December 6th, 2007, 09:56 AM

Quote:

Originally Posted by Chris Hurd

.... it's certainly possible to use a 4:3 sensor and crop it to get 16:9, which Canon did with the XL2, as I've explained here: http://www.dvinfo.net/canonxl2/articles/article06.php

Yes, he's correct regarding SD cameras. However, I'm not saying that you can't crop a 4 x 3 sensor to 16 x 9, just that HD cameras don't do it that way.

December 6th, 2007, 01:27 AM	#25
Eric Pascarelli Major Player Join Date: Nov 2007 Location: Los Angeles, CA Posts: 498	To further that point, Chris, I would suggest that if there were in fact a "bad" depth of field, it would be shallow DoF and not the deep DoF of these small format cameras. In 35mm film production, much effort and money is expended to get "enough stop" to hold focus for a particular scene - to hold focus between an actor's eyes and nose for example. This can mean doubling the amount of lighting equipment, pushing the film or whatever. In so many cases in the past (another example is miniature photography) I would have loved to have been able to use one of these miraculous cameras with which everything is in focus! Over the past decade, with the rise of small format digital acquisition and post, shallow DoF has become a sought after effect and not simply a byproduct of the medium. This is is exemplified when I work with CG artists who might ask me "do you want me to add more depth of field to that?" And I say "no - there's already too much - make the the background softer" Our definitions of DoF are opposite - to me, more depth of field means deeper depth of field. To them it means shallower DoF, because in their world, everything is in focus, and "depth of field" is a filter that's added in post. 35mm adapters are lovely, but at times I think that they are superfluous added "effect" - a shortcut to an appearance of quality at the expense of other qualities. There are plenty of ways to tell a great story while embracing the small format medium and its wonderful deep DoF. Last edited by Eric Pascarelli; December 6th, 2007 at 02:02 AM.

December 6th, 2007, 09:39 AM	#29
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	That's true Brian, but the post by Carlos that you're referring to: http://www.dvinfo.net/conf/showpost....6&postcount=22 ...makes it clear that he was speaking about the standard definition Canon XL2. And he's right, it's certainly possible to use a 4:3 sensor and crop it to get 16:9, which Canon did with the XL2, as I've explained here: http://www.dvinfo.net/canonxl2/articles/article06.php __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

December 5th, 2007, 04:41 PM	#16
Vince Gaffney Regular Crew Join Date: Dec 2005 Location: Chicago, IL Posts: 146	And here's the CMOS version from silicon imaging. it's near the bottom http://www.siliconimaging.com/ARTICL...#cmosimgerchar vince or just go here and look at the sizes http://www.dvinfo.net/conf/attachmen...3&d=1196679037

December 5th, 2007, 04:55 PM	#17
Noah Yuan-Vogel Major Player Join Date: Dec 2004 Location: New York City Posts: 613	perhaps this is of some help: http://www.dpreview.com/news/0210/02...ensorsizes.asp http://www.panavision.co.nz/main/kba...eframelist.asp unfortunately, these are not always consistent between cameras... notice that at 2/3" on the panavision site there are several listings for different dimensions. there is no listing for 1/2" 16:9 so its hard to say if the ex1's 16:9 adopts the 4:3 1/2" specification's height or width or diagonal. according to that chart, 16m film actually has a diagonal of about 11mm, 1/2" cmos about 8mm, and 8mm film about 6mm so 1/2" is somewhere in between standard 8 and 16mm film

December 5th, 2007, 05:05 PM	#18
Noah Yuan-Vogel Major Player Join Date: Dec 2004 Location: New York City Posts: 613	who knows, maybe the vignetting issue some people have is because sony went with a 16:9 1/2" sensor that is 8.5x4.8mm, but the lens is intended for 4:3 1/2" sensors and they were too generous with how they came about 16:9 from the normal 1/2" sensor format. totally pulling that out of thin air but that would explain some things.

December 5th, 2007, 05:10 PM	#19
Carlos Moreira Regular Crew Join Date: Nov 2007 Location: Spain, Barcelona Posts: 27	yes. this might be the explanation - its set too close. If you resize the sensor vertical from 16:9 to 4:3 you get a higher diagonal value. Tis also explains the good DOF. calculated in 4:3 the sensor may be just a bit smaller then 2/3. could somebody please cut off the glass to have a look ? ;-)

December 5th, 2007, 05:39 PM	#20
Brian Drysdale Inner Circle Join Date: Feb 2006 Location: Belfast, UK Posts: 6,152	No HD camera is 4 x 3, they're all widescreen format.

December 5th, 2007, 05:53 PM	#21
Noah Yuan-Vogel Major Player Join Date: Dec 2004 Location: New York City Posts: 613	right, although its not unheard of for a camera to have a 4:3 sensor and crop to 16:9. the canon hv20 does this with its 1/2.7" sensor. i was just suggesting the ex1 might do the opposite by expanding horizontally instead of cropping vertically. there does not seem to be that much information on sensors that are 1/2" and 16:9. perhaps we might learn more if we look at sony's other 1/2" xdcams. there are plenty of machine vision 1/2" cameras that are HD-like resolution but most of them are 4:3.

December 5th, 2007, 05:55 PM	#22
Carlos Moreira Regular Crew Join Date: Nov 2007 Location: Spain, Barcelona Posts: 27	this not an issue of HD or not but a simple question of sensor dimensions. You can also use a 4:3 sensor and crop it to get 16:9 popular example is the XL2. it has 1/3 4:3 sensors which are cropped for 16:9. the result is a smaller real size and really bad DOF.

December 6th, 2007, 12:15 AM	#23
Eric Pascarelli Major Player Join Date: Nov 2007 Location: Los Angeles, CA Posts: 498	I've never seen the actual spec, but my best guess is that the active area of the imager is 7.2mm wide x 4.05mm high. The first reason that I think this is the measurement is because 2/3" HD cameras are widely known to be 9.6mm x 5.4mm. 2/3" times .75 = 1/2" and so multiplying the 2/3" chip dimensions by .75 gives me the above figures (of course I know that chip sizes are based on old vidicon tube dimensions and hence are not so neatly proportional as this). The second reason is from measuring the field of view and distance with a tape measure. At full wide, 5.8mm, I measured the distance to a wall, and the distance between two tape marks on the wall placed at the left and right edges of frame. This gave me enough information to calculate the chip size, assuming two things - that the lens focal length is really 5.8mm and that the EX1's monitor shows the whole frame with no cropping (in fact it does not, but it comes close). From these measurements I estimated 6.54mm width. I did the same thing at full tele, 81.2mm. The number I got was 7.75mm, with the same two assumptions. The dimensions 7.2 x 4.05 fall neatly between these two estimates. It's clear to me that the actual lens focal lengths on the EX1 are a bit different from the lens markings. I don't believe the lens goes quite as wide or as long as its markings indicate, but that's for another thread, and I can certainly measure that definitively once I find out the size the 1/2" HD chip. If someone finds the actual dimensions of the active area of the EX1 chips, please let me know.

December 6th, 2007, 03:30 AM	#27
Carlos Moreira Regular Crew Join Date: Nov 2007 Location: Spain, Barcelona Posts: 27	when the DOP / director WANTS or NEEDS the DOF to bee deep it is a free artists decision. But if he wants to have a shallow DOF and can´t archive it due to technical limits of the camera, it´s simply bad. And of course I always can get a (more) shallow DOF when using tele, but this also means a very long distance from camera to object and no chance to get shallow DOF on in-room shots. Even the EX-1 has a bad DOF for me, but it touches the lower range of what is useful. For me the DOF of the EX-1 looks close to 16mm.