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Old Nov 9, 2007, 10:07 AM   #431
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dongdongliushui wrote:
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I read from an article that some HD camcorders use interlaced CCD (eg. Canon XL H1 andSony HDR-FX1/HVR-Z1U), while some use non-interlaced CCD (eg. JVC GY-HD100). Non-interlaced CCD provides native progressive scan mode (720p in JVC's case), but interlaced CCD can only provide "faux" progressive mode, that is emulated progressive mode, something like doing de-interlacing from interlaced videos. See: http://www.eventdv.net/Articles/Read...rticleID=37864

Obviously, non-interlaced ccd should do better in its native progressive mode, and vice versa. Now I just wonder if HD1000's cmos is interlaced or not. If it'snon-interlaced, then 720p should be its native modeand we might better stay with its 720p mode. If it's a natively interlacd cmos, then the 1080i mode should do it best, and the 720p mode is not real, but emulated!

From Sanyo's official material, it looks very likely HD1000 uses a interlaced cmos (フルHD動画60field/s対応、1920x1080i高速*み出しを実現。 Full HD video 60 field / s corresponds, 1920 x1080i fast readout realize. 全高清錄像60*/秒對應,1920x1080i快速讀取實現). Thus HD1000 does not have a native 720p mode, right?
I may be wrong but I am fairly certain now that the 1080i mode in our awesome HD1000 is the only mode that is not progressive. The term fields is only used in this particular instance (when the manual refers to 1080i)in all literature and there is definately a 720 p mode which I will use most of the time unless I have a really gorgeous shot I want to capture :-)

I am going on vacation soon and I am planning on shooting in 720p and 1080i as well as 640x480p shot for shot if I can, just for the benefit of having all the standards covered.
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Old Nov 9, 2007, 10:50 AM   #432
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Hey all..... Anybody got suggestions for a decent video light? I got a 20W halogen lamp off ebay pretty cheap and it works well but it is nearly as big as the HD1000 itself which is not really a problem as I wont be using it that often. I find the 20W not really enough though. I was looking at a Jessops 35W lamp which I think will do the job. I was also thinking of Sunpak 15W which gets good reviews regarding light but battery life is terrible (15mins max). Thanks.

Please dont suggest the camerabright as I had one for my CG65 and as I showed in another thread its pretty useless!

I've been reading the HD700 forum regarding comparing the HD1000 and HD700. Interesting.......

EDIT....

NOTE TO SELF.... ALWAYS MAKE SURE BATTERIES ARE NEW!!!!!

I bought new batteries for the 20W light and its fantastic!!! Bought from ebay for £10.99. 20W is perfect for what I need.
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Old Nov 9, 2007, 3:32 PM   #433
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TheTurk wrote:
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[...]NOTE TO SELF.... ALWAYS MAKE SURE BATTERIES ARE NEW!!!!![...]
:lol:
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Old Nov 10, 2007, 10:39 AM   #434
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dongdongliushui wrote:
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I just wonder if HD1000's cmos is interlaced or not. If it'snon-interlaced, then 720p should be its native modeand we might better stay with its 720p mode. If it's a natively interlacd cmos, then the 1080i mode should do it best, and the 720p mode is not real, but emulated!

From Sanyo's official material, it looks very likely HD1000 uses a interlaced cmos Thus HD1000 does not have a native 720p mode, right?

Dongdongliushui,

This is a very interesting point that you bring up about how the CMOS sensor is scanned. And it appears that the issue is even more complicated. The Sanyo literature refers to a"pixel alignment method" to gain more light, which suggests getting as much light sensitivity as a progressive scan while doing interlaced scanning.

"Full-HD recording with even higher quality has been achieved through a new pixel-alignment method that gathers more than twice as much light information as the 1920 x 1080 pixels of the full-HD specification."
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Old Nov 10, 2007, 6:52 PM   #435
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But if the CCD has 4 megapixels for real, it means there is no real match line for line of the output image, so what's the benefict of interlaced CCD scaning or progressive CCD scaning, and it's relation with the output format?...

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Old Nov 10, 2007, 7:13 PM   #436
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Mikexilva,

I think that the video mode only uses the middle 2 mega-pixels of the sensor. In the specs, you will notice that the equivalent focal lengths for video are longer (narrower) than those for photos (49mm equivalent vs. 38mm at the wide end of the zoom). I think that the electronic image stabilization moves that 2MP field around on the sensor to compensate for motion. When you take a photo while shooting "full HD" video, you only get a 2MP image.
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Old Nov 10, 2007, 7:51 PM   #437
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Yes, it makes sense, does it mean the 720p mode have beter image stabilization than 1080p? (at least is has more free space in the border.

By the way, I think the software image stabilization have to detect motion vectors to compensate unwanted hand moving.

The H.264 (and previous algorithms as well) also have to calculate motion vectors to beter find diferences from one image to next image.

Just for my curiosity are both this software operations made by the same chip and same gates? I think it sould be, because there sould be more efecient

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Old Nov 10, 2007, 8:46 PM   #438
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i'm sure the 720p modes still use the same chip area for recording as the 1080i mode. so the EIS doesn't perform any different than when in 1080i mode. If they reduced the recording area for the 720p mode, the field of view will be different. Plus the 720p mode seems much sharper than the 1080i mode, which i suspect is because the image is downsampled.

I seem to remember that the xacti's (since CG6) uses gyro sensors in combination with the software for the stabilization.
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Old Nov 10, 2007, 9:44 PM   #439
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I always asked myself: is it was possible to reduce the resolution (downsizing the output pixel count) and increase the light sensivity (simply by adding the light in near pixels) ?.

But never heard about this subject.. is there any pratical problem adjecent with this "simple low light enhacement" ?

It cound even make an automatic trade between resolution and light sensivity...
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Old Nov 10, 2007, 10:02 PM   #440
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in previous xacti models like cg/ca 65, they did bin pixles together for increasing low light sensitivity... and its possible hd700 does it too as it's 7 megapixel sensor has enough pixels to bin down to 1280x720 (720p)

HD1000 doesnt for the obvious reaons that there isn't enough pixels to bin down. but it does have bigger photosites since it only has 4 megapixels on the chip.

I previously suggested that the hd700 might have better low light performance because even though it has smaller pixels... binning during filming probably gives it the advantage (since it uses the entire 1/2.5" chip area for the 720p, instead of hd1000's using of the center crop for its 1080i output).

However people who own both hd700 and hd1000 stated that the hd1000 performs much better in every aspect including low light than the hd700.

Although do keep in mind that they use different sensor technologies even though they have the same size sensor (1/2.5"). HD700 uses CCD while HD1000 uses CMOS.
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