Pixel Count of CCDs for the last time maybe?

B

Barry_Green

Moderator
Posted this on DVInfo in response to another thread, but I felt like it's too choice of a demonstration to leave it buried elsewhere.

I know pixel count is on everyone's minds, but I'd like to demonstrate why it doesn't necessarily mean diddlysquat.

Hopefully this can forever settle the question about the relevance of the CCD's pixel count. This post was in reference to someone who has continually tried to find out the pixel count to demonstrate that it's lower than his chosen camera, the native-pixel-count JVC HD100.

So I propose that you have to decide one of two choices: either pixel count is important, or it is not. Only one of those two can be true, correct?

If it is so important, then obviously one must abandon the JVC immediately, since the Canon offers 69% more pixels than the JVC does. The Canon offers 1,555,200 pixels vs. the JVC's 921,600 -- that's a difference of 68.75%. If pixel count is so important, one must stay true to their convictions and go with the Canon and forget the JVC (and everything else).

So the only valid reason to stick with the JVC then would be to admit that pixel count doesn't really matter all that much, right?

So let's see how important pixel count is, in translating to actual defined resolution in an image. Here's a great, great, great example. Compare these two res chart extractions. One is from a 378,840 pixel standard-def DVX100 using the Andromeda, and one is from the 921,600 pixel JVC. So if pixel count is so important, the JVC shot should have roughly 2.4x as much definition as the Andromeda, right?
Andromeda-vs-HD100.JPG



Ummm... Hmmm. Son of a gun. Maybe overall pixel count isn't such a big thing after all? Maybe it's actual resolved image definition that's a bit more important perhaps?

The Andromeda is showing equivalent horizontal resolution from its 770 pixels (vs. the JVC's 1280) and it's showing substantially higher vertical resolution from its 492 (vs. the JVC's 720). The Andromeda-ized DVX with 378,840 pixels is showing a sharper image than the HD100 with its 921,600 pixels.

I for one don't really care what the pixel count is, as long as the resolved image definition is competitive. And Juan Pertierr of reel-stream has shown us how you can get equivalent definition (and arguably BETTER definition) from as few as 770x492 pixels. Sounds to me like as long as the HVX has at least 770x492 pixels it'll be capable of delivering an image at least as sharp as the JVC HD100. And, guess what, it does. Here's an extraction from those two cameras:
HVX-vs-HD100.JPG


The JVC shows higher horizontal, the HVX shows higher vertical, and each shows equivalent amounts of edge enhancement, with the overall edge in sharpness going to the HVX.

(res chart extractions taken from the originals posted here: http://forum.reel-stream.com/viewtopic.php?t=363)
 
Well now we know what has been done, Panasonic Andromeda-ized a DVX and called it the HVX :) ....and added a few little features as well...
 
What these charts (and other andromeda footage) are proving is: everything that comes behind the digitizing of the CCD has a much bigger impact on the image quality than we thought.

Who cares if the pixels are 960x720 or 1080x820 when the in-camera downconverting throws away so much information.
It's like a sportscar that's been limited to 80 mph. It doesn't matter if its a ferrari or porsche, they all have a lot of hp, but can't use them.

DVCProHD is nice, but I want the option to record the best possible image from the camera as well.
Take a look at the digital still camera market. Even the inexpensive point'n'shoot cameras have the option to record raw images. But we poor "prosumers" are stick to "medium jpeg quality".
 
Great example Barry

But...... confused....... this brings up an interesting question and that is; how the hell does andromeda get a sharper image out of the DVX with older CDD's than Panasonic can get out of the HVX with the latest lot?

People have been going on about '... the lens on the HVX wont be able to get that resolution anyway' - yet here it seems pretty clear that the old DVX lens and ccd is outperforming the HVX new lens and ccd (at least in terms of resolution and sharpness - it was always good enough). I certianly expected the HVX to outperform a DVX mod.... why does this seem just wrong to me?

Does this have something to do with 4:4:4 or are the people at reelstream just better at tweaking than Panasonic?

If there was a device that could record the andromeda signal to DVCPROHD I think this would be a far superior image with greater lattitude too.

If the guys at reelstream get hold of the HVX I wonder what they could produce. Seems to me that Panasonic did not get the Max out of the DVX and maybe so with the HVX too.

But, I must be missing something here, it's like 1+1 dont make 2 anymore.
waaaaaa
 
Okay, this was my post on the topic at DVinfo:

"Right, we all agree that the HVX horizontal resolution isn't great? From what I have seen it is worse than the vertical.

So why is HR lower than VR? The lens shouldn't favour one axis and the codec has more pixel horizontally than vertically.

That leaves the DSP and the CCDs. Maybe the pixel shift favours vertical res?

BUT, maybe the CCDs have higher vertical res than horizontal. That would also explain why Panasonic won't release the CCD info! It would look pretty odd if they admitted it used 576x720 CCDs wouldn't it.

Hey, I'm just throughing a new spanner into an old debate :)"
 
mmm, to know the actual horizontal resolution you have to multiply the chart result with 1,77 (the 16:9 apect ratio)... that guves a horizontal res of aroung 1200...

so, the HVX200 res could be around 1200X800
 
Rodrigo said:
mmm, to know the actual horizontal resolution you have to multiply the chart result with 1,77 (the 16:9 apect ratio)... that guves a horizontal res of aroung 1200...

so, the HVX200 res could be around 1200X800
Click to expand...

I thought a 16:9 chart took that into account but I'm probably wrong.

Anyhow it was just an idea of what they "might" have done.
 
if it took it into account then the horizontal numbers would go up to 1200 and beyond... i'm guessing here as well since I am only a tech aficionado
 
There's no way to be certain, but possibly the people building the HVX were more concerned with things like P2 support, frame-rate upgrades, etc., than simple resolving power? I mean, usually, when I watch a movie, I'm not staring at the vertical lines on the wall trying to see if they blend together. Although there have been times, when the movie was really boring...
 
This image came through a lens right? What is the lens doing to the chart? First we say don't compare specs, just compare images, then we say look what these charts prove?

The "shoot out" sure said other wise didn't it and it didn't consider pixel count. Also, pixel count needs to take into account pixel size. The larger the pixel the better sensitivity to light. There is probably a fine line to walk here as well.
 
The only caveat here being that the Andromeda doesn't do any of its processing in camera. It's all done after capture where time can be taken to do things to the best degree possible. Juan and reel-stream have been breaking some new ground with their 'demosaicing' technology. I'm not aware of anyone else who has experimented with their ideas and I would be surprised if you could do the equivalent processing in camera.

Barry's point is still quite valid of course (not trying to crush it). What matters most is resolving power of the system in total not necessarily pixel count. Clearly people have underestimated the lens on the DVX (and likely the HVX lens too) for instance!

The Andromeda is showing equivalent horizontal resolution from its 770 pixels (vs. the JVC's 1280) and it's showing substantially higher vertical resolution from its 492 (vs. the JVC's 720).
Click to expand...

Indeed! It's an impressive piece of work! I'm reading over 800 horizontal lines and maybe 740 vertical from the andromeda. Am I seeing things (serious question here)? I noticed that the image looks different when zoomed in on with photoshop vs windows picture viewer. Maybe I'm going crazy and need to compare the two again! =)
 
CCD has vertical dimension 3mm, lens 80l/mm, we must double pixels to read lines. We will recive 480 - vertical rosolution. Am I wrong?.
 
Not 800 horizontal lines!

Not 800 horizontal lines!

the 800 lines Andromeda result is 4:3 lines. 800*4/3=1066pixels which is 1066*9/16=600 tv lines. 600lines limited by the chart. Probably a little more with a real 16:9 shooting. Nothing THAT impressive!
 
Right but unless I'm reading the chart improperly (don't usually read these things) the 800+ lines of res is on the horizontal axis so you don't loose any when cropping vertically. Not impressive for a cinealta or similar but quite impressive given the source of the footage which matches or exceeds most of the low price HD(V) cams on the market right now.
 
I don't want to start a 720 vs. 1080 debate here, but there are some things to consider before you lock on to the higher number. Looking at just the pixel resolution, one can assume that there's a lot to be gained by going to the higher 1080 resolution, right? Well, not as much as you think with the 1/3" CCDs. Take a look at the data presented by Adam Wilt:


HDW-F900/3 CineAlta 2/3" 1920x1080p 1000h+ 1000v+
Canon XLH1 1/3" 1440x1080i 800h- 700v+

AJ-HDC27F Varicam 2/3" 1280x720p 700h+ 700v+
JVC GY- HD100U 1/3" 1280x720p 700h 700v


SEE: http://www.dv.com/features


If we compare the Canon to the JVC, you'll see that in the vertical direction there isn't a lot to be gained by going to 1080. In the horizontal direction it's less than 100 lines we gain. That comes out to be around a 14% improvement in resolution; not a whole lot.

Now compare the Canon to the F900 and we see a big jump in the resolution. No surprise here, because we're look at a bigger CCD and a better lens. The problem is that no 1/3" CCD really fully resolves all the detail. If we are wanting true 1080 detail, a MINIMUM of a 1/2" CCD will be necessary. Shooting 1080 with a 1/3" CCD is like up converting 720 to 1080. You have all the pixels, but not the real detail that 1080 could provide.

If we compare the JVC with the HDC27F, there is a slight improvement going to a 2/3" CCD, but not much. While a larger CCD is always going to give a better image, in terms of resolution, a 1/3" CCD holds up very well against a 2/3" CCD. It is not unreasonable to shoot 720p and be able to resolve the detail. Realistically, any 1/3" CCD; JVC, CANON, Sony, or Panasonic is only able to resolve 720 worth of image anyway and 720 does look good when blown up to a big screen.

While the Andromeda resolution is interesting, it is from their test shot and not a mass produced camera, correct? It will be interesting to see what independent tests show.


My personal belief is that the Panasonic's Native CCD resolution is 960h x 720v. There is a slight chance it could be 960h x 810v. For those who wish to read all the details, see messages 1 & 8:


http://www.dvxuser.com/V3/showthread.php?t=45801


Assuming I'm correct, I'm VERY happy that the engineers at Panasonic wisely chose this resolution. Increasing the pixels does little to increase the captured detail, BUT it does lower sensitivity and increases the problem with noise and dynamic range.


In the end, there is one simple fact, for an under $10,000, 1/3" CCDs, the image looks great.


Bob Diaz
 
You are a good poster Diaz but it seems, at least to me, that you are trying to justify yourself at the end of your posts if not always, almost always.

I know you always have so much care with the Panasonic brand in order to say always what they want to hear but please you don't need to mention always that bla bla bla $10,000 bla bla bla 1/3" CCDs bla bla bla the image looks great...

...no one is gonna be bite you! :)
 
soarprod said:
Well now we know what has been done, Panasonic Andromeda-ized a DVX and called it the HVX :) ....and added a few little features as well...
Click to expand...

I don't think so - The DVX + Andromeda has more res than the HVX
 
filmmaker1977 said:
You are a good poster Diaz but it seems, at least to me, that you are trying to justify yourself at the end of your posts if not always, almost always.

I know you always have so much care with the Panasonic brand in order to say always what they want to hear but please you don't need to mention always that bla bla bla $10,000 bla bla bla 1/3" CCDs bla bla bla the image looks great...
Click to expand...

Ummm... filmmaker... did you read the post? Bob is not pandering, he's summarizing. Chomp to you!
 
ullanta said:
Ummm... filmmaker... did you read the post? Bob is not pandering, he's summarizing. Chomp to you!
Click to expand...
Ummm... ullanta... as you already must know it's not my opinion... He's a nice poster but he's always politically correct or I must say Panasonically correct?...
 
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