View Full Version : Is 1/2 that much better than 3/4?
Tyson Persall September 20th, 2007, 04:40 PM I should probably know this already but thought id ask.
I understand that 1/2 is better than 3/4 sensor because its bigger which allows more light to enter the iris. Thus, better in low light.
But is this the only advantage?
Will I notice a difference in well lit shots between a 3/4 and 1/2 inch camera?
Jiri Bakala September 20th, 2007, 04:50 PM I should probably know this already but thought id ask.
I understand that 1/2 is better than 3/4 sensor because its bigger which allows more light to enter the iris. Thus, better in low light.
But is this the only advantage?
Will I notice a difference in well lit shots between a 3/4 and 1/2 inch camera?
I believe you are actually thinking 1/3" or 1/4" sensors. The sensor sizes go from smallest to biggest:
1/4"
1/3"
1/2"
2/3"
2/3" is a standard broadcast camera size and its advantage over the smaller chip sizes is better low light performance and shallower DOF (depth of field). The 1/2" of the XDCAM line of cameras is better than most of the 1/3" or 1/4" cameras because the sensors are physically bigger and can capture more light (the low light performance) and also optically allows shallower DOF.
It's the amount of light reaching the sensor that is important (not the iris). A 3/4" sensor would be actually better yet than the 2/3" but it is not used in TV cameras, to my knowledge.
Hope this helps.
Thomas Smet September 20th, 2007, 06:21 PM There is also the fact that it is just too hard or near impossible to do a 3 chip camera where the chips have 1920x1080 pixels with 1/3". The 1/3" chips are just too small and generate way too much heat to pump out that many pixels.
So far pretty much every single HDV camera and even the HVX200 have had to use some sort of trick to get around the size limitation of the 1/3" chips.
The JVC series of HD cameras so far has been the only sub $20,000 camera that actually offers the true native resolution of the format it records to. To do this however they had to split the image block into two halves. All the 1080i cameras have had to use either a single cmos chip, pixel shifting, or a funky method of rotating the chips to overlap to pull out extra detail. All of these methods work very well but they are not as pefect as a raw clean feed from a 1920x1080 set of chips.
There is also the theory that when you have pixels that small that the details will kind of get blended together anyway because the light hitting those puny chips just doesn't have the precision to get details the size of one pixel. The 1/3" lens also plays a part in this. A 1/2" lens will allow more precise light to hit a 1/2" chip.
So really with HD unlike SD having 1/2" is really the mininum to have the full amount of detail you could have with HD. I'm not sure if a 1/3" HD camera could ever resolve the same level of detail due to those limitations.
With all that however it is pretty much overkill. You will be hard pressd to find people who woud stare at their screen and tell you that something looked like it was shot with a 1/3" camera. While there is a difference between 1920x1080 and 1440x1080 it is so small that only the ones who insist on zoomig into a still shot to find missing detail will ever really notice.
Tim Polster September 20th, 2007, 09:12 PM With all that however it is pretty much overkill. You will be hard pressd to find people who woud stare at their screen and tell you that something looked like it was shot with a 1/3" camera. While there is a difference between 1920x1080 and 1440x1080 it is so small that only the ones who insist on zoomig into a still shot to find missing detail will ever really notice.
Actually, I would disagree with this statement.
It is quite easy to tell the 1/3" cameras from their bigger brothers when it comes to image quality and dynamic range.
Sure, 1/2" chips are better for lowlight, but to me the best part is the image quality that is gained.
1/3" chip cameras even though they are loved have visible limitations when it comes to handling highlights. They tend to look harsh when it comes to highlights and often lose color detail before larger chipped cameras with the same exposure.
The larger chip cameras just give a more refined, balanced image to my eyes.
Chris Hurd September 20th, 2007, 09:16 PM To your eyes, Tim... no argument there. But I'll maintain that many folks can't tell the difference at all. My next door neighbor. My aunt in Montana. My most recent client.
Tim Polster September 20th, 2007, 09:46 PM Chris, you are right.
I stare at images so often that it is hard to remember what it was like before did this kind of work.
I have also noticed that having the ability to see the difference is expensive as well!
Thomas Smet September 21st, 2007, 12:19 AM Yeah I can tell too but then again thats why I get paid to play this stupid game. Like Chris said I was talking about the normal people who don't spend their days and nights sitting on DVinfo. It also depends on what camera you are talking about. There is no way to group every 1/3" camera into one group because they all have different looks to them. Some have more detail then others. The Z1 is clearly a notch behind the 330 while a Canon Xh1 has been known to hold it's own next to a F900 in certain shooting conditions.
My whole point is that the lines between "oh my god" and "thats nice" are getting smaller and smaller. In most cases with any form of HD camera you are going to get a "oh my god." It is ture however that 1/2" does have better image quality so if you think your clients can tell the difference then I would be more worried that they are about to steal your job and/or your other clients.
David Heath September 21st, 2007, 03:56 AM Whilst you may struggle to tell 1/3" camera pictures apart from their bigger brothers in good conditions, it's when the light goes down that the differences become evident.
John Bosco Jr. September 21st, 2007, 04:07 AM I should probably know this already but thought id ask.
I understand that 1/2 is better than 3/4 sensor because its bigger which allows more light to enter the iris. Thus, better in low light.
But is this the only advantage?
Will I notice a difference in well lit shots between a 3/4 and 1/2 inch camera?
If there was a 3/4 inch sensor (.75 inch), it would be the best of all; however, 2/3 inch sensors (.67 inch) are the largest currently. 1/2 inch sensors (.50 inch) are better than 1/3 inch (.33 inch) and 1/4 inch (.25 inch) sensors. Just think that in terms of sensors bigger is better.
Michael Mann September 21st, 2007, 05:43 AM Tyson, don't forget about narrower depth of field.
In that respect 1/2'' vs. 1/3'' or 1/4'' is quite a difference.
Jiri Bakala September 21st, 2007, 07:40 AM If there was a 3/4 inch sensor (.75 inch), it would be the best of all; however, 2/3 inch sensors (.67 inch) are the largest currently. 1/2 inch sensors (.50 inch) are better than 1/3 inch (.33 inch) and 1/4 inch (.25 inch) sensors. Just think that in terms of sensors bigger is better.
Enter Red One - full size CMOS sensor, essentially emulating the 35mm film in many aspects. At a price, of course. And Dalsa, Arri D20 and some others too. So, yes, there are bigger sensors but in a different category of cameras.
A 3/4" sensor would be perhaps nice, although I am not sure how much better it would really be over a 2/3" - but the main issue is that there are no lenses and the implementation would be very costly and impractical at this point. You may as well just jump straight to the full size.
Kevin Shaw September 21st, 2007, 08:24 AM But I'll maintain that many folks can't tell the difference at all. My next door neighbor. My aunt in Montana. My most recent client.
I have clients who can't see an obvious difference between good widescreen DVDs and full-quality footage from my FX1s, but even for them I suspect footage from the EX1 would be pleasing at a subtler level. Plus the EX1 should yield very nice frame grabs, something I wish was better with my current cameras. If nothing else the EX1 will provide extra assurance that you're getting the best image quality one could realistically hope for in this price range, with no excuses for your pickiest clients.
What I'm wondering is how the EX1 will affect interest in higher-end HD cameras, since it may yield close to the limits of quality that can actually be delivered to home viewers in digital form. As Thomas said the difference between 'oh wow' cameras and 'that's nice' are getting smaller, and the EX1 seems poised to set a new standard of price versus quality.
Josh Laronge September 21st, 2007, 08:36 AM If there was a 3/4 inch sensor (.75 inch), it would be the best of all; however, 2/3 inch sensors (.67 inch) are the largest currently. 1/2 inch sensors (.50 inch) are better than 1/3 inch (.33 inch) and 1/4 inch (.25 inch) sensors. Just think that in terms of sensors bigger is better.
Are sensors are measured on the diagonal? If so, then the Red would be a 1.1" sensor.
Peter Jefferson September 21st, 2007, 09:06 AM "So far pretty much every single HDV camera and even the HVX200 have had to use some sort of trick to get around the size limitation of the 1/3" chips"
Actually dude, the Canon H1, G1 and A1 all have native 1920x1080 sensors... at 1/3 sensor, and downscale simply to be compliant with the HDV codec requirements
Steven Thomas September 21st, 2007, 09:30 AM RED sensor specs:
Sensor 12 Megapixel Mysterium™
Physical Size 24.4mm x 13.7mm (Super35mm)
Active Pixel Array 4520 (h) x 2540 (v)
Full Pixel Array 4900 (h) x 2580 (v)
Dynamic Range > 66dB
Depth of Field Equivalent to 35mm Cine Lenses (S16mm with windowed sensor)
So it appears to be a 16x9 sensor with the horizontal at almost 1".
From what I'm hearing and seeing from some footage/grabs, it's extremely clean and fairs very
well even at higher ISO.
I'm not on the order list, but I have a buddy who is. I'm looking forward to checking it out soon.
Greg Boston September 21st, 2007, 09:32 AM Actually dude, the Canon H1, G1 and A1 all have native 1920x1080 sensors... at 1/3 sensor, and downscale simply to be compliant with the HDV codec requirements
With all due respect Peter, those cameras have native 1440x1080 1/3 inch sensors. The current XD HD is also native 1440x1080, but 1/2 inch.
But the point remains the same. Thomas was a bit off with the claim that no 1/3 inch chip available had HD resolution.
There is also the theory that when you have pixels that small that the details will kind of get blended together anyway because the light hitting those puny chips just doesn't have the precision to get details the size of one pixel.
This is where on chip lens technology helps. It gathers and focuses light precisely onto each pixel. That has helped to make some of the smaller sensor size cameras more sensitive over the last several years. That technology is also used on the 1/2 XD HD cameras.
-gb-
Thomas Smet September 21st, 2007, 10:26 PM With all due respect Peter, those cameras have native 1440x1080 1/3 inch sensors. The current XD HD is also native 1440x1080, but 1/2 inch.
But the point remains the same. Thomas was a bit off with the claim that no 1/3 inch chip available had HD resolution.
-gb-
I never said a 1/3" wasn't HD. In fact I even said most people would find it very hard to tell them apart. What I did say is that as far as I know no 1/3" 3 chip camera has the full 1920x1080 pixel raster while actually resolving that much detail.
Alister Chapman September 22nd, 2007, 02:42 AM Isn't the XL-H1 1920x1080?
Chris Hurd September 22nd, 2007, 03:35 AM Actually dude, the Canon H1, G1 and A1 all have native 1920x1080 sensors... at 1/3 sensor, and downscale simply to be compliant with the HDV codec requirementsDead wrong. Actually the Canon H1, G1 and A1 all have native 1440x1080 sensors.
Isn't the XL-H1 1920x1080?Nope... see above... the Canon XL H1, XH G1 and XH A1 (same chips in all three camcorders) are definitely native 1440 x 1080. From there, they get a resolution boost from Pixel Shift in the horizontal axis, so it's practically "as good as" 1920 x 1080, but most assuredly native 1440 x 1080.
...as far as I know no 1/3" 3 chip camera has the full 1920x1080 pixel raster while actually resolving that much detail.Quite correct. There is no 1/3rd-inch three-chip camera that has the full 1920x1080 pixel raster. The maximum in the 1/3rd-inch realm is the CCD used in the Canon XL H1 & XH camcorders, at 1440 x 1080 (and pixel shifted from there).
Hope this helps,
John Bosco Jr. September 22nd, 2007, 05:18 AM Are sensors are measured on the diagonal? If so, then the Red would be a 1.1" sensor.
I forgot about the Red One. You are correct the sensor size is over an inch. A 3/4" chip wouldn't be that great a difference over a 2/3rd inch, like mentioned in another reply.
Barry Green September 22nd, 2007, 07:56 AM Are sensors are measured on the diagonal? If so, then the Red would be a 1.1" sensor.
Yes they are measured on the diagonal, but... no sensor is anywhere near the size that is reported. A 1/2" sensor does not, in any stretch of the word, actually measure 1/2". That's why the proper nomenclature is to say that it's a 1/2" TYPE sensor.
For example, a 2/3" chip doesn't measure .667 inches (17mm) across in any dimension; it's actually 9.6mm x 5.4mm, for a diagonal of about 11mm, or 0.433 inches. Yes, a 2/3" chip actually measures less than half an inch.
So, if one were to classify the Red One sensor by the diagonal measurement, using the same terminology as existing video sensors, it'd actually qualify as a 1.7" type sensor. About 2.5 times larger, on the diagonal, than a 2/3" sensor.
John Mitchell October 17th, 2007, 10:08 AM FYI after attending the Sony demo on the EX the way they get away with processing so much information is there is an A to D converter on each of the 1980 rows of each sensor. So no danger of a split screen effect with this cam :)
Sony have done a good job here of speeding up processing with parrallel processing and this also minimises heat and therefore noise. Being CMOS you can also point this cam at a light or a sunset with no smear problems.
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