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June 21st, 2005, 12:56 AM | #1 |
Major Player
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With stabilization Sony HC1 has 25% lower res INCORRECT
The image stabilization is electronic. It says sensors are used.
Here is translated Japanese brochure. See all detailed information. U.S. product pages are joke. 10:1 zoom in U.S. brochure is 41-480 mm. http://hdvforever.com/hdv/hvra1j/default.htm http://hdvforever.com/hdv/hdrhc1/default.htm Animated pictures in brochures mean video. It appears there are two video modes, full scan, uses 1920x1080 pixels and 1440x810 mode. Image stabilization needs extra pixels; Super Steady Shot is probably using those extra pixels. So with SSS resolution drops 25% horizontally and vertically. Without SSS you'll get same resolution as FX/Z1. Effective pixels in FX/Z1 always 1440x1080, because horizontal pixel shift. Because Bayer filter, which means 25% resolution decrease, in HC1 you'll get 1440x1080 effective pixels, without SSS and 1080x810 with SSS. There is something else. Full scan mode is described in prosumer camera; consumer model could have lower resolution all time, but it is unlikely. More notes: The microphone is very short shotgun with 2 elements for each channel. That is revolutionary. Camera seems have manual exposure. It does have zebra patterns. Radek |
June 21st, 2005, 08:50 AM | #2 | |
Obstreperous Rex
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Your statement about the color filter is also misleading and fundamentally incorrect. The Bayer pattern incurs some slight loss of resolution, but you are ignoring the complicated reconstruction algorithms employed by the DSP to recover that information. I really do not appreciate the sort of sweeping claims you're making, not just because they're technically inaccurate, but primarily due to the fact that you have not yet actually seen the image output of this camcorder with your own eyes. This is the DV Information Network, not the DV Supposition Network. Be advised that I have personally escorted a few misguided individuals from our boards for the exact same sort of misinformation that you're attempting to spread here. My primary issue with this is that you're stating your claim as if it were a fact, even though you really do not know it to be true. If you had phrased it in the form of a question, that would be altogether different -- even encouraged, as I appreciate all questions. Radek, you list your occupation as a student. I'd like to encourage you to step back and assume a role of *learning* around here. This can be an excellent place to learn. Thanks in advance, |
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June 21st, 2005, 11:16 AM | #3 | ||
New Boot
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At 2000$ tag price it would be really a surprise to not have OIS (is there any other consumer camcorder at this price range without it). But maybe Sony engineers disovered that only vertical shake is important to stabilize image ? We have to wait to see it. BTW. As some info appears about limited manual control available on HC1, it looks more as HC1 is similar to HC90 with exception to: - CMOS intead of CCD (is CMOS cheaper?) - DSP microprocessor ready for HD (costs about 50-80$?) - worse low-light performance (7 lux versus 5 lux) So what justify 2000$ price, HC90 with 3Mpx CCD (able to do HDV 1920x1080, but lacking proper DSP) costs 600$. I hope that most informations available now about HC1 are incorrect. [EDITED] Quote:
Regards |
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June 21st, 2005, 11:26 AM | #4 |
Inner Circle
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CHris I agree with some of your comments AND some of Radek's. NEITHER of you know if pixels are reduced when Super Steady Shot is on for this camera at this time. The camera appears to have electronic image stabilization so must use extra pixels from somewhere for this to work. These could be extra pixels that are there all the time or as Radek infers reduce effective source pixels while SSS is on. Please don't tell me that Super Steady Shot is optical and doesn't use extra pixels, I have a Sony TRV50 with Super Steady Shot and it is electronic, so is my Sony PC10. However both these cameras use large pixel count CCD's giving plenty of data for the DSP to work with and retain full pixel count for the DV image. In this case you are correct that the resolution is not reduced with Super Steady Shot but there is clearly less data available to the DSP for image enhancement so this could impact exposure depending on light levels. Your comments about the tone of Radeks post have some merit( have you thought that English may not be Radek's first language?) We will all have to wait just a few weeks to find out. Until then we will all make the assumption that information from any source on the WEB( that includes company sites) is just that. It becomes fact when it becomes absolutely verified personally or by several independed sources that say exactly the same thing( one source doesn't cut it even if its Adam Wilt!).
Ron Evans |
June 21st, 2005, 04:16 PM | #5 | |
Major Player
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Quote:
Radek Last edited by Radek Svoboda; June 21st, 2005 at 11:39 PM. |
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June 21st, 2005, 04:22 PM | #6 |
Obstreperous Rex
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Super SteadyShot is Sony's brand for its highest quality image stabilization. It can be either an optical process (OIS) or electronic process (EIS). In either case, Super SteadyShot implies that there is no discernible loss in image quality. When it's electronic, it usually involves a surrounding area of pixels on the the image sensor that have not been previously dedicated to the image area itself.
Besides, normal EIS technology has dramatically improved within the past 24 or 36 months and is nowhere near as bad a hit on image quality as it used to be, thanks to primarily to improvements in the DSP. That's a crucial concept to understand. Image quality trade-offs due to EIS are inherent in older camcorders, not new ones. There is no longer such a dramatic difference between OIS and standard EIS as there used to be. I firmly agree with Ron Evans that nobody really knows for sure about the C1 and A1 just yet, and that we'll only have to wait just a few more weeks to find out. My primary point is that I would like to strongly caution some of our members here to put forth their ideas in the form of a question -- think of the American game show, "Jeopardy" -- I'll take image stabilisation for $200, Alex. There is no faster route to alienization around here than to preach conjecture as fact; especially when it's inaccurate. Thanks in advance, |
June 22nd, 2005, 10:58 AM | #7 | |
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Regards |
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June 22nd, 2005, 01:26 PM | #8 |
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As I understand from the specs, the CMOS sensor has 2.97M gross pixels - but only uses 1920x1080 - or just over 2M pixels for normal 16x9 video. So it seems to me that there are plenty of pixels available for electronic stabilization without compromising the resolution.
Considering the 1440x810 still resolution, I think that because the H-resolution of the video must be reduced from 1920 to 1440 for recording in the HDV standard, then all video data would go through this data reduction as a first step. Then in order to keep a square pixel shape for the still picture the vertical resolution must be similarly reduced (x0.75) hence 810. However, there is also the possibility that Sony actually converts the vertical resolution of the 1080 video frame to 810 to reduce the processing power for the MPEG encoding required for recording - then interpolates back after MPEG encoding (much easier because much less info in the MPEG encoded signal) to record the correct 1440x1080 on the tape. Of course, 1440x810 derived resolution would still be recognised as HD because the unofficial definition of HD is anything greater than 1M pixels. If you are not recording video then you can get the full pixel count in a still picture - i.e. 1920x1080 in 16x9 mode or 1920x1440 in 4:3 mode. Gerald |
June 22nd, 2005, 01:37 PM | #9 |
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As I understand from the specs, the CMOS sensor has 2.97M gross pixels - but only uses 1920x1080 - or just over 2M pixels for normal 16x9 video. So it seems to me that there are plenty of pixels available for electronic stabilization without compromising the resolution.
Considering the 1440x810 still resolution, I think that because the H-resolution of the video must be reduced from 1920 to 1440 for recording in the HDV standard, then all video data would go through this data reduction as a first step. Then in order to keep a square pixel shape for the still picture the vertical resolution must be similarly reduced (x0.75) hence 810. However, there is also the possibility that Sony actually converts the vertical resolution of the 1080 video frame to 810 to reduce the processing power for the MPEG encoding required for recording - then interpolates back after MPEG encoding (much easier because much less info in the MPEG encoded signal) to record the correct 1440x1080 on the tape. Of course, 1440x810 derived resolution would still be recognised as HD because the unofficial definition of HD is anything greater than 1M pixels. If you are not recording video then you can get the full pixel count in a still picture - i.e. 1920x1080 in 16x9 mode or 1920x1440 in 4:3 mode. Gerald |
June 22nd, 2005, 02:57 PM | #10 | ||
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It doesn't matter if still are independently done from 1920x1080 to 1440x810 or after the first step of reducing video to 1440x1080. The second option is practical - needs less power and gives exactly the same output. Quote:
Regards |
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June 23rd, 2005, 09:30 AM | #11 |
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Regardless, I think the HC1 should have optical image stabilization for the price but I really can't recall any single CCD/CMOS Sony cam with anything other than electronic/digital image stabilization.
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June 23rd, 2005, 09:58 AM | #12 | |
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The thought about power reduction in the mpeg conversion was that there is always an electrical power budget for a portable device so any way to reduce the actual power consumption of the conversion process would be welcomed. Less processing speed = less power consumed! I forgot however that the HDV signal is interlaced so it would actually be a lower data rate than a de-interlaced 810. Anyhow, somehow Sony has managed to get the total power down to under 6W (excluding LCD) which is quite an achievement. FX1 is 7.4W under same conditions, with most of the additional power being for CCD processing probably (much of the CMOS initial processing is done on the chip). I understand from a FX1 writeup that the chip used for conversion to mpeg actually takes only 200mW so that supports your argument that mpeg conversion is no problem! Gerald |
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June 29th, 2005, 12:48 PM | #13 |
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The stabilization concept in the HC! is most probably one that combines OIS and motion vector analysis. (cfr Canon super range OIS) The system involves a standard OIS with gyro sensors and VAP or lens shift optical correction elements. In addition those systems perform motion vector analysis for the lower vibration frequency components (gyro's have difficulties to detect low frequency shaking), but instead of changing the read out zone of the sensor the motion vector information is fed back into the OIS actuators. So. OIS is used EIS is partly involved. and there is no need for extra pixels,
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July 3rd, 2005, 05:16 AM | #14 | |
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On resolution loss with single chip camera:
http://www.dvinfo.net/conf/showthrea...page=193&pp=15 Quote:
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July 3rd, 2005, 09:42 AM | #15 | |
Obstreperous Rex
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