AF101 BBC/EBU test results posted

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danap said:
To make my point clear: I only argue that this camera has been shipped with a significantly lower resolution than advertized. The difference between 800 lines (low compared with the EX1) and 610 clean lines is very significant for wide shots. I am also arguing that what I have got is not a "HD" camera. I am not talking about other cams and 4K.
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I don't know how people are getting 610 lines. In my own tests I am getting at least in the 700's.. and thats on a print out. I'm gettin 800 or more diagonal lines. Previous cameras people would claim a camera resloved x anount of resolution even if the lines weren't completely clean. All of a sudden the standards got more strict. Not that I am sayin I'm not dissappointed though. Especially since we see how detailed the gh2 is.
 
imdjay said:
sorry astigmatic but you're still missing the point that he was making. even if you get your walmart 4K camera it probably won't resolve 4K, just like the 1080 af100 isn't resolving 1080. so no, 4K will not end anything. And no, threads are not proof that 4K is a "need", that's subjective. There is plenty of data on the side of the argument that 4k isn't needed for the majority, but i have yet to see data which is on your side of the opinion.

In either case moore's law will eventually make 4k for 5K(dollars) at some point in the future, i just don't give a damn, it's a silly pedestal to be pining over
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Again, you;re missing the point that I was not addressing his point. lol

And because you don't need 4k doesn't mean others don't. For example, films with heavy compositing and grading. Shooting with anamorphic lenses then having to crop. Needing high rez frame grabs for advertising. 4k tvs.
 
astigmatic said:
Again, you;re missing the point that I was not addressing his point. lol

And because you don't need 4k doesn't mean others don't. For example, films with heavy compositing and grading. Shooting with anamorphic lenses then having to crop. Needing high rez frame grabs for advertising. 4k tvs.
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nope, i got that :), the point was your comment was directly related and pertinent. you are correct that heavy compositing can benefit from higher res, but i would venture to say that the vast majority of people on these forums and users of these level of cameras aren't doing heavy compositing. i could be wrong but i just don't see a mass of sci fi/effects movies being produced here let alone heavy effects movies using cameras in these price ranges. perspective is all i'm sayin ;)
 
I find it typical that Jan Crittenden is very quiet on this matter. I will get my camera's this week, and I know now that I will be very disappointed about the sharpness of the picture. If you buy an HD camera, one expects an HD picture and not something in between. If the camera produces 700 lines i.s.o. 800, Panasonic has been cheating. If it can be corrected in the firmware, no sweat, but if it cannot, one can sue Panasonic for that.
This is unacceptable, what a waste.
I sold my EX1. I should have kept it to shoot the wide shots.........................
 
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Beyond the resolution issue, I think there's a major clue about the nature of the AF100's image quality in Roberts' report. Note that when evaluating this report's circular resolution charts in the PDF document, it's important to view them at precisely 100% magnification, as the aliasing patterns will be altered at other magnifications. Here's a link to the report:

http://thebrownings.name/WHP034/pdf/WHP034-ADD66_rev_2_Panasonic_AF101.pdf

First, Roberts calculates the AF100's native image sensor resolution as about 4700x2644, which matches Panasonic's 12.4 Megapixel spec. With an RGBG Bayer Filter sensor, this should contain an array of 2350x2644 green pixels, interspersed in a grid among a pair of 2350x1322 red and blue pixel arrays. This should provide enough precision to support Full HD 1920x1080 resolution.

According to Roberts, however, the measured resolution of the AF100 in FHD mode is only about 1210x680, which is very close to half the 2350x1322 red and blue pixel resolution. He also highlights an unusual property of the green pixel resolution chart:

Alan Roberts said:
...there is clearly very little difference between the [red and green colors], the levels of aliases are identical. This implies that the green signal has been derived from the sensor at the same resolution as that of red and blue, which must be about 2350x1322...
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If, as Roberts suspects, the AF100 samples green pixels at the same resolution as blue and red pixels, this could explain how Panasonic manages to virtually eliminate color-fringed aliasing patterns from its resolution charts, which is the type of aliasing that notoriously plagues the Canon 5D Mark II:

http://thebrownings.name/WHP034/pdf/WHP034-ADD39_Canon_5D_DSLR.pdf

The drawback of Panasonic's technique, however, is the detrimental effect it has on the camera's FHD image resolution. According to Roberts' analysis, Panasonic has apparently chosen to allow aliased edge-sharpening to substitute for the missing high-resolution image details:

Alan Roberts said:
It is also clear, from the double-frequency pattern in the middle [of the resolution chart], that the lens is passing frequencies up to nearly twice that of 1920x1080, since the vertical spatial alias reappears above the sensor resolution limit. This is an indication that there is either no optical low-pass filter, or that it is inadequate.
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A camera whose image sensor lacks an effective optical low-pass filter may produce very sharp-looking images, because high-contrast edges will be artificially exaggerated by alias-generated artifacts. But since the AF100's alias patterns are free of telltale color-fringing, its aliased artifacts will likely blend into the image with a far more natural appearance than the garishly colored aliases produced by the 5D Mark II.

If this is in fact the way the AF100 has been engineered, then I doubt there's much Panasonic could do to improve it further. While the aliasing that Roberts objects to could be reduced with a better low pass filter, that would also make its poor image resolution more noticeable.
 
I would really like to get to the bottom of this 800 lines of resolution conspiracy...Is it or isn't it...Who makes the final decision as we have some that say yay! and some that strongly suggest Nay! Personally, If it really turns out that the camera 100% without a doubt shoots less than 800 and I am talking significantly less. Then I strongly feel Panasonic should remedy this issue quickly. Or at least make a statement as to how they tested this cam to be 800 lines. Common now, if you make a product and believe in it then stand up for it. Its not that its not a pretty picture...but its like advertising a new Toyota as having a v6 and really you pop the hood and it has a i4...yeah it still drives, it probably gets better fuel economy, maybe it runs softer...but you bought it thinking it had a v6...well sure it only cost you 5,000 bucks...and if you wanted a v6 you should have bought that shiny beemer...but damn...you can't help to feel a littttttleeeeee jibbed.

This being said...yes. I have gotten nice picture out of my AF100...but the point is did I get what was advertised? That is TBD. I would expect this camera to have at least the same resolution of a GH2 as it is the same sensor. Yes, its a nice thing to have waveform and over under crank plus timecode...god how I missed timecode. I loveee timecode.


anyways...It is a very pretty camera to look at. I just want the truth!


But you can't handle the truth.


BOOM. goodnight
 
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I find it typical that some people seem to think that people like Jan owe them something rather than being thankful for their involvement. And I'm surprised that people like Jan hang around with the number of jack ass coments directed at them.

And the comment on sueing is possibly the dumbest thing I've seen written on these forums.
 
Yea, I saw that thread on Vimeo too.

Like everyone else on this thread, I question why Panasonic says 800 lines while other people are coming up with several other numbers. Whether or not the BBC approves my current camera is not really of concern to me, because I am not going to produce any content for them. However, I would like to find some answers for the discrepancy. These sorts of issues are part of how I determine my future upgrades in equipment.

I remember the whole conversation about compromised vertical resolution when the HVX200 and XHA1 were first coming out as the HD indy cameras of choice. That seemed to be the compromise of the time around 2006. Why is this still going on now?

I really do think that the images I can get from the AF100 are beautiful, and I have already paid off my camera with enough gigs. Although, I am concerned about discrepancies in published performance compared to actual performance. Each upgrade in my equipment is an important investment. That is true for my camera and all of my equipment.
 
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I mean...the GH2 has a different OLPF than the AF as well...you would think that might just be the culprit just because it appears to be the same sensor.
 
This all reminds me of the HVX native chip size debacle... For a few weeks we all decided our HVXs were not good enough... well we're still using ours, and in fact used it on a number of shoots for Discovery last year, mixing with the original varicam and the EX1. All looked great at the end of the day.

But indeed, Panasonic seems a very secretive company (Jan excepted) with sometimes seemingly very confused priorities (see the GH1 firmware issue after the GH13 hack). I wouldn't expect any answers from them soon.
 
I have already asked them. But if you've turned on the news recently, you might notice that the Japanese folks have their hands kind of full right now.
 
artyswiss said:
I guess the question also is what is real HD resolution? Companies like Comcast advertise HD video signal...but they compress their HD signal about 39% to about 18 or less mbps. Do we really have a clear definition for hd signal besides 1920x1080 even youtube has "HD" thats not HD...but people use that word all the time.
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I am totally with you. Most of us on here work "HD" production in some form or another--professionally or for a hobby. We work in some master format, and eventually we compress our work for some form of delivery. Broadcast "HD" companies compress their footage even further. Most people outside of our world that I talk to are still confused about the differences between 1080p, 720p, and 1080i. I meet a lot of people who are thrilled with SD video delivered in a 16:9 aspect ratio.

I understand the compromises we are taking by using affordable indy cameras. However, I will be annoyed to learn that the published 800 lines of vertical resolution is not true. I purchased the camera with that belief. I am no pixel peeper, but I consider my equipment to be an investment in my career. It is true that the shooter is more important than the camera. I develop my skills more and more every year, but I need my equipment to meet my expectations.
 
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blackcat said:
I will be annoyed to learn that the published 800 lines of vertical resolution is not true. I purchased the camera with that belief. I am no pixel peeper, but I consider my equipment to be an investment in my career.
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This summarizes the point I tried to make earlier. What I want to emphasize is that this discussion about clean resolution is not an issue of "taste" but rather, here in Scandinavia, and elsewhere in Europe, a clear legal issue, which might involve either the Consumer Protection Authority, or worse, the Marketing Authority (to protect the market from false advertisement).

I am expecting legal complaints to be filed against Panasonic for misleading advertisement here in Europe. This is why Panasonic would be wise to come out of the box rather quickly, since the AF100 "issue" is gaining momentum in the professional community and the company's silence (antedating the quake btw) may damage their business reputation.
 
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