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July 7th, 2004, 08:02 AM | #31 |
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that last link looks like part of that PDF that i found the other day detailing Pana's entire range of CCD's =)
it's a goodun =) |
July 7th, 2004, 08:33 AM | #32 |
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If somebody could please enlighten this confused and sleepy head :-)
Vertical resolution is the same as no. of horizontal lines??? How are horizontal lines of resolution such as 500, 510, 520, 530 and 540 achieved if the maximum vertical resolution is 480? Goodnight from Tokyo :-)) |
July 7th, 2004, 08:54 AM | #33 |
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It is confusing terminology, but you have your horizontal and vertical confused. If your screen was a spreadsheet the rows would be vertical lines and the columns would be horizontal lines. The complete DV image consists of 480 vertical lines (rows) and 720 horizontal lines (columns). The spec that you usually see on camcorders refers to the horizontal resolution, which is the number of dots running from left to right than can be resolved (actually this gets complex, so this is a simplification).
Generalizing again, resolution is measured in a square area of the image, so the maximum number of vertical lines is 480. Measuring from left to right you need to take into account that the pixels are not square and have an aspect ratio of ~.9. So in the same space as the 480 vertical pixels you would have 480/.9 = 533 horizontal pixels. Therefore the maximum horizontal resolution in DV is about 530 lines. Now maybe someone with a little more tech know-how can elaborate on this, but I think this explains the general concept... |
July 7th, 2004, 06:57 PM | #35 |
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Here's some more explanations.
http://videoexpert.home.att.net/artic1/201res.htm http://members.aol.com/ajaynejr/vidres.htm#Example1 |
July 11th, 2004, 08:49 AM | #36 |
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If in fact all CCDs progressively scan, as was suggested by a previous poster, but most have the scanned lines read in an every-other interlaced pattern, how does this explain the inter-line blurring in still captures of moving subjects from interlaced video?
If the lines are actually captured in one progressive sequence per frame, even if they are read and transferred as interlaced, that should reduce or eliminate the inter-line blurring of moving subjects. This does not happen with footage from an "interlaced" camera, as stills from moving subjects are usually blurred, to some degree. A related feature to this is demonstrated by Sony's "progressive-shutter", used to capture still pictures without blurring, on an interlaced-scanning system. All the lines are captured from the same short open-shutter period, so no motion blurring occurs between adjoining interlaced lines. Anyone who can decipher and understand what I just wrote, could probably clear up this incongruity. Steve McDonald |
July 11th, 2004, 11:14 AM | #37 |
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> Anyone who can decipher and understand what I just wrote, could
> probably clear up this incongruity. Jjajajaja yes, I'm sure ;-) First of all, as far as I have been able to grasp from some of the stuff that has been linked, no, some CCD chips are not progressive capable at all. When you freeze a frame of video from an interlaced sensor, depending on the software used and such, you are usually freezing a frame which contains one set of lines from one instant in time (one field) and another set of lines from another instant in time (the other field), so you when things are moving from one instant to the next, you get that characteristic interlaced double image. You can either discard half of the lines and duplicate or interpolate from the others (and thus lose 50% vertical resolution), or combine and resample the information from both sets of lines (and also lose some resolution but not as much). I don't know which one of the two, but Sony digital still cams that lack a real progressive scan sensor use one of these methods. My old Mavica had a "frame" and a "field" mode where you could enable or disable this. When there is little or no movement, it is better not do deinterlace and you get full resolution, but when there is movement you can get rid of the motion artifacts by duplication or interpolation. I am not sure if the newer Sony digicams have real proscan CCDs, continue to have frame/field modes or simply deinterlace behind the scenes.
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July 11th, 2004, 10:27 PM | #38 |
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Boyd,
Good analogy with the spreadsheet. To take this horizontal resolution thing a bit further, here is my understanding. Horizontal resolution rating is pretty much an indicator of the quality of glass on the camera. My 953 is rated at 570 lines while the XL-1 lense resolves over 600 lines. Hence, the XL-1 produces a 'sharper image' on the 720 horizontal spreadsheet columns(to use your analogy). Broadcast camera lenses tend to be rated at 800 or above meaning they have 'the sharpest' image projected onto the 720 horizontal pixels. I understand of course that high end cameras also achieve superior images with more than good glass, but I'm just illustrating a point. Put another way, let's say you and I have identical resolution (720 pixels) on our retinas (ccd's). However, your cornea (lense) is better than mine so you would have 'clearer' vision. regards, |
July 15th, 2004, 06:31 AM | #39 |
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I spent almost an hour playing with both the black and silver GS400 last night. Didn't want to put the cam down but the store was closing :-).
When you activate procinema mode, the LCD displays the Jap word "Procinema" on the upper left side and directly under it, the Jap word "Frame" is also displayed. The GS100 does not do the same thing. |
July 15th, 2004, 04:22 PM | #40 |
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So, Allan, what do you conclude from that? Does the picture degrade in that mode versus interlaced widescreen, for example? From the videos you posted, it seems that procinema and widescreen modes have similar resolution.
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July 18th, 2004, 03:08 PM | #41 |
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Getting back to the press release. The marketing person seemed to be saying the gs400 has more in common with the dvx than with the gs200 or previous dv953. The chart clearly shows they are capturing a full progressive image and saving it as 2 interlaced images (like 30p of the dvx). Now all of you are saying this is not so? Who to believe....
btw... Simplified Horizontal resolution for the math challenged is the number of vertical lines going from left to right... example... ||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Simplified Vertical res is the number of horizontal lines from top to bottom example... _____________ _____________ _____________ _____________ _____________ NTSC rectangles are wider than tall PAL rectangles are taller than wide. Thats why when converted to square PC pixels you end up with more vertical resultion to work with in you nle. (very simplified answer to PAL resolution). And if the gs400 is true 30p/25p then I may buy it. But not if it's only 'fake' progressive (frame * 2). The marketing person seems to want this to be the camera for those who want the dvx but can't afford it. |
July 18th, 2004, 04:51 PM | #42 | |
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Quote:
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July 18th, 2004, 09:31 PM | #43 |
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<<<-- Originally posted by Joe Carney : Getting back to the press release. The marketing person seemed to be saying the gs400 has more in common with the dvx than with the gs200 or previous dv953. The chart clearly shows they are capturing a full progressive image and saving it as 2 interlaced images (like 30p of the dvx). Now all of you are saying this is not so? Who to believe....
Like I previously posted, EXACTLY the same explanations and illustrations were given by Panasonic Japan with the PROCINEMA function of the GS100, the black mamba to some. There are enough members of this board who own the GS100. So what do they say about the Procinema feature of their cam? Just how difficult is it to replace the word FRAME by PROGRESSIVE in both the menus and the LCD displays? I am no Japanese but I think I have familiarize myself enough to know how painfully detailed and accurate and practical they are when in comes to choice of words and classification, especially for technical terms. This is a country that calls X-Ray as Roentgen. The marketing person seems to want this to be the camera for those who want the dvx but can't afford it. -->>> That marketing person better learn some Japanese first and talk to Panasonic Japan. Yes of course, he wants those who can't afford the dvx to buy the GS400. From all Japanese sites I have read, including the first reviews, the common thing emphasized is the Crystal Engine (technology). Panasonic Japan is very clear that the GS400 does not have Progressive Scan CCD, but now, I am not sure at all if such type of CCD is required in order to be "true progressive scan capable." They said they would get back to me on the resolution under Procinema/Frame Mode and I am still waiting for that :-( Yesterday, I took 2 minutes of sample videos inside the store using the GS400, approximately 10 seconds each under all 6 settings. (Normal Interlaced, Wide Interlaced, Procinema, Normal Frame Mode, Wide Frame Mode, and Procinema again). If anybody here has the knowledge and equipment to analyze the footages to find out whether Procinema or Frame mode is progressive scan or whatever, I am willing to send him or her the tape. I can't do it :-)) BTW, whether it is actually progressive scan or frame mode, and regardless of the still capability (I have NOT used my black mamba to take any stills), I think this high-end (consumer) cam is a nice buy...d_mn I paid more than 1.5 times for my Optura100. Yes Guy, I admit the Procinema sample looks great compared to widescreen interlaced mode. I cannot make any conclusion but my best guess/opinion is, Frame Mode PLUS Crystal Engine :-)) |
July 18th, 2004, 09:58 PM | #44 |
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Ok, Allan, we have it. Frame mode not 30P. But, it still looks great!
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July 19th, 2004, 09:59 PM | #45 |
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the issue for me is in the nle when editing. In vegas (and other nles') that can properly handle 24p, you get a full 720x480 picture to work with. With frame mode you get the same limitations of trying to convert interlaced to progressive for uprezing or changing to different formats. If frame mode, I'll just keep my mx500 and keep saving for another camera. Still nice to read all the posts about it. I'm sure Panasonic appreciates all the free publicity.
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