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March 22nd, 2003, 05:59 PM | #1 |
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MX300 Optical Stabilizer
According to my NV-MX300EN/A manual, Page 37, "...you can use the Optical Image Stabilizer Function to stabilize the image. Using this function does not deteriorate the picture quality." However, in Panasonic's 2 page "New Product Information" brochure, it says, "This advanced optical system uses more than 90% of the effective pixels captured by the CCDs, so there is no loss in picture quality even with the image stabilizer function on." Furthermore, with the new firmware version 1.6, which supposedly "fixes" the optical image stabilizer (somewhat from what I read), I'm curious to know what the degradation of the image actually is. 10%? 30% with the original firmware?
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March 22nd, 2003, 11:55 PM | #2 |
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I just read some TRV900 info about it's optical stabilizer. You know, using google to find stuff because there's nothing on TV except for those talking puppet heads yapping up the---. Anyways, there was a blurb about the stabilizer. It said there was some degradation, but it didn't say how much.
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March 23rd, 2003, 01:47 AM | #3 |
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I did a test where I fixed the MX300 and the TRV900 to the same horizontal bar, aimed their viewfinders at the same point about 3 metres ahead of me, and went out a-filmin'. On replay it was obvious that although both camcorders have OIS, the Sony one is much more powerful and useful.
So then I did some tests with the OIS turned off, and try as I might I couldn't see any gain in picture quality. The only time I could see the OIS working was when I was shooting straight into the light and in those conditions you can see the flare spots from the OIS elements moving independantly from the fixed elements. Oh, and if you have a 4:3 lens hood that is very close to the edges of your frame (i.e. at its most efficient) then the start of a pan can show vignetting in the corners of the frame. With OIS turned off you don't get this of course. But as regards optical degredation Frank, no - I simply cannot see this at all. OIS is as transparent a facility as I've ever seen on a camcorder, and the most useful. tom. |
March 23rd, 2003, 01:54 AM | #4 |
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The member, angryofMayfair, noticed the TRV900 stabilizer to be better as well.
The 10% is mentioned by Panasonic---it's written in the PDF brochure; for me, as for you, I cannot tell one way or another. |
March 23rd, 2003, 08:17 PM | #5 |
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Hi, all.
Some facts & a question (I don't know the answer, I'm looking for it...): Sony consumer DV cams, with OIS on, shoots at MINIMUM 1/100th of a second shutter speed. With the OIS off it can shoot at lower shutter speeds. Our Pana MX3000 with OIS is able to shoot at MINIMUM 1/60th (1/50th PAL). Well, not counting the GAIN mode's 1/12 or 1/15. Do you think that if the Pana with OIS on, shot at 1/100th it would help lessen the degradation, if any? After all, the higher the shutter speed, the less "blurring" we get... |
March 24th, 2003, 03:14 AM | #6 |
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Thanks Tom for sharing that with us.
Steven, I think you're on to something here. I think a faster shutter would capture a better image, but the movement in the footage would still be there. Solution: tripod/fluid head. |
March 24th, 2003, 11:05 AM | #7 |
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Most EIS systems up the shutter speed to 1/100th (PAL) when you engage the image stabilisation, and it's another very good reason to head for the cameras fitted with OIS. Who wants to loose a stop in sensitivity just because you want steadier pictures? Just think - you have to double the amount of light in the room just to have your EIS turned on.
All EIS systems suffer from several problems. One is that because the actual image is moving across the face of the chip, image shakes induce motion blur. Even though the position of an image may be perfectly stabilized, you can often notice a transient blurring of the image along the direction of the shake. Sometimes it's quite noticeable. To get around this, the shutter speed is invariably increased when the EIS is turned on. This not only means a wider aperture must be used, or more gain (= grain) applied, but fluid motion (of camera and/or subject) is harder to achieve with the higher shutter speed per frame. And why the increase in shutter speed? Well it's not as you might expect to "make the movie sharper" and therefore somehow steadier, it's because subject movement - especially when using a tripoded camera - is seen by the EIS as movement that must be corrected, so the EIS does its pixel search and actually destroys the static steadyness that you've used a tripod for. Optical is the answer, even though ithe mechanism is more expensive, heavier, bulkier, noisier and uses more battery power. For all these disadvantages it has one huge advantage: it works better. tom. |
March 25th, 2003, 08:07 PM | #8 |
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wow, I'm learning lots! Thanks!
What about those hybrid systems that I've heard about - I think it's Sony's "Super Steady Shot" in the latest Sony cams, not sure. Where you have a sort of level / gyroscope system near the front of the lens, which tells the cam how much it is being shaken, and they somehow tie back to the EIS so that they know which part of the CCD to sample. And how does the MX's optical system work? Level / gyroscope system coupled to prism? Free standing prism? |
March 26th, 2003, 01:56 AM | #9 |
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Confusingly, Sony use their terminology "Sony Super Steadyshot" (SSSS) on cameras that have EIS as well as those that have OIS. The latter are subdivided into the vibrating element(s) principle and the VAP (vari-angle prism).
The MX300/350 and 500 use the vibrating elements deep within the lens assembly and I've written extensively about this elsewhere on these forums. As you say, this system is blind to the image, and takes it's information from camera movement, moving the OIS doublet in response to this movement. As such it's happy to work in the dark or in low contrast situations that would have an EIS system in total confusion. You can always see the prism (VAP) systems just by looking at them Steven. Have a look at the Sony VX2k and the TR2000, the Canon GL2 (XM2), the XL1-s - they all use this VAP and they all have the characteristic lens bulge that houses the activating pistons and electronic drivers. tom. |
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