A demonstration of my higher end consumer grade video camera modification to a Sony HDR CX-350v. After getting a Sony factory service tech to recalibrate the focal drive unit (the hotplate somehow works in tandem with the autofocus program mode), in order to regain use of this camera.
Although the focus system's software is statically fixed in the unit's firmware, mechanical values can be adjusted in the service mode software for the focus drive motor to compensate for the loss of visible light reflecting edges the DSP Program so desires to adjust the focus. But due to the fact this camera is stuck in permanent Program mode, that has very little adjustable user parameters, when operated as a full spectrum night vision cam, there is a noticeable lag on the focal system. When all else fails the system appears to simply focus in on the hotest / brightest item in frame. In this video I held the light in my other hand and you can see as it attempts to folow the brightest area with the focus motor. Focus gets slightly better when stabilization is turned off and you are not fully zoomed out. Anyone who has used this camera knows its non-zoomed field of view is very broad, so broad, that the IRIS at full open state creates a softer image around the edges. This can be compensated for by using a non-coated fisheye lens and zooming in slightly until the soft region sharpens up. All low light night vision cameras experience this effect to some extent if their native field of view is as broad as the CX-350v.
To summarize focus issues I have noticed; they are solved using a fisheye and a few bumps on the zoom lever. You are still left with a very good field of view.
One can compensate using point to focus mode, face detection focus mode, or user controlled manual mode.
This is the only major drawback to this mod.
The backlit Sony CMOS sensor is superior is it's unfiltered range of detection in terms of chromaticity. It's native, fully exposed pixel design really shows on the low and far end of what is percieved as color and beyond. It's price point can only be trumped by cameras such as Canon's XA10 which has a much larger sensor and pixel transitors. (1/4" vs 1/3")
But almost all consumer and professional cameras that offer night vision, interpolate chroma values into a combined color value which is directly modulated in terms of amplitude by the overall luma value of the pixel. Think B&W or CNN Desert Storm Green... (tm.)
This camera has shown sensitivity to a 365nm "doggie pee light," and when I attempted to video that, the pee pee didn't floress. That is good because if your using this as a parnormal investigation tool, what little video evidence of manifestations that exist on the web doesn't appear to show floressed light just the original anomally, imaged at the original chroma value.
Using florressed light to detect UV light activity is a hack anyway; since floressed light chroma values are multiples of the the original light resonating and reflecting at a much higher, visible light value.
Which is an even better effect that in low light levels the sensors DSP seems to up the gains on the far ends of the spectrums, while attenuating the middle portion of the visible band.
In visible light, the effect seems to go from a U curve to a more flattened, even chroma value gain level.
So this camera is usable in visible light, possibly outside. The exposure iris will shrink, letting less light in. But I am not going to hold my breath, sunlight will destroy a fragile CMOS sensor without notice, if not shielded from harmful lowband UV rays it can't even begin to detect. That is what a hotplate is for. Though it's possible a medium density filter with UV and IR coatings could be used as a preventative measure. Though accurate color will only be attained with the original hotplate in place.
Due to how this camera works I see no reason to attenuate the visible band since the DSP compensates on the fly for low light, and provides reasonable performance without the inherant attenuation a filter adds to the overall light passed through it. A visible cut filter will always attenuate the non visible light it passes to a measurable extent.
Why lower your chances if your already in the dark???
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Hd Test 60p Sony hdr cx 360v Stunning Qualityby 12345mike67895,316 views
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