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Old Nov 17, 2009, 10:23 AM   #11
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K O D A K over s a ms u n g I preferre to have viewable footage LOL
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Old Dec 16, 2009, 4:13 AM   #12
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These cmos sensor hybrid cams all seem to have the same ultimate sensor sensitivity due to the 2.2 micron pixel size, so the low light performance is really down to the lens speed. Most of the cameras have a lens around f3 because it is the best tradeoff of low cost with acceptable sharpness. The Sanyo HD2000 lens is f1.8, which is the fastest stock lens for this type of cam that I know of and should make it the low light champ.

I modified a DXG 595v to accept C mount lenses (a horribly complicated procedure I wouldnt recommend) and have tried a wide variety of lenses on the camera including the fastest security camera lens available, f0.75. The sharpness isn't super since this is a security camera lens, but it isn't bad either especially in low light where noise would otherwise be a problem.

-Eric
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Old Dec 19, 2009, 9:29 PM   #13
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- Which fixfocus mini/hybrid camcorder is suited best for lowlight indoor video?

Yes, I want one of those motorless simple digital zoom things. I don't demand perfectly clear Hollywood quality; some snow would be ok. However the 2 I yet found made a completely black picture or a purple snowstorm and so were absolutely unusable for this.
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Old Dec 22, 2009, 10:57 PM   #14
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The zi8 has turned out reasonable, but I do not know if it is the best.

Remember, that fixed focus is a compromise. To maintain sharpness and resolution they use a narrow aperture, that lowers the amount of light getting to the sensor, lowering low light quality, and will have different amounts of blur at different distances (unless very narrow aperture). A variable focus allows for faster aperture and more light, but focus will be limited to a much narrower plane of the image.

Newer sensor technology allows for great low light performance at narrow apertures, but we are still waiting for them to come to hybrids.
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Old Dec 22, 2009, 11:10 PM   #15
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Quote:
Originally Posted by wbamb833392 View Post
I modified a DXG 595v to accept C mount lenses (a horribly complicated procedure I wouldnt recommend) and have tried a wide variety of lenses on the camera including the fastest security camera lens available, f0.75. The sharpness isn't super since this is a security camera lens, but it isn't bad either especially in low light where noise would otherwise be a problem.

-Eric
I would like to know more about this. You may find that the security lens is suffering from a lack of a IR filter, possibly even an uv filter, to increase the amount of light to the sensor, this will probably increase the blur and scattering. I picked myself up a IR/UV+filtering for extreme blue to compensate for this on any camera I might need it for. Another problem is that sensors, particularly with micro lens, or worse with 3 chip prisms, have a problem handling extreme angles of light from extreme apertures. You might find that backing off the aperture to f1.3-1.6 might help.
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Old Dec 23, 2009, 8:17 AM   #16
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I just bought the Aiptek PocketDV T300LE on eBay. Despite it is far from perfect, the lowlight performance is at least not completely unuseable. In most situations the picture is at least not fully black. It is still way less sensitive than my eyes, but at least it makes a picture in light situations where I can well read newspapers (the T100LE didn't).
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Old Dec 29, 2009, 2:19 PM   #17
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Quote:
Originally Posted by Wayne12 View Post
I would like to know more about this. You may find that the security lens is suffering from a lack of a IR filter, possibly even an uv filter, to increase the amount of light to the sensor, this will probably increase the blur and scattering. I picked myself up a IR/UV+filtering for extreme blue to compensate for this on any camera I might need it for. Another problem is that sensors, particularly with micro lens, or worse with 3 chip prisms, have a problem handling extreme angles of light from extreme apertures. You might find that backing off the aperture to f1.3-1.6 might help.
The IR cut filter was built into the stock zoom lens, so when I converted to C mount I added a new IR cut filter atop the sensor. It cuts off at 700nm instead of the stock 650nm, so scenes are a bit more red, but they aren't blurry from IR. Reflective IR cut filters only work well in a narrow range of angles, so while it is possible to add it outside a telephoto lens, the best place functionally is to put it near the sensor. For normal daylight filming and ease of focusing I usually set the f stop around 3 or 4. Focusing is the real challenge with the lousy little LCD screen on this camera. The one trick I've figured out is to focus on something with a grid pattern and focu until the moire pattern is worst.

The lower sharpness comes from the security camera lenses themselves, which are designed for about 40lp/mm versus 120lp/mm for a stock lens on one of these HD cameras. That difference shows up on the micro scale where the textures seem fuzzy. If you know what soft focus looks like, that's the look. Of the 10+ lenses I have tried, only one was unacceptably soft, a Tamron F1.2 6-60mm model.

The Aptina sensor allows a chief ray angle of 7 degrees, which is fine for a C mount lens and I have noticed no vignetting even with the f0.75 lenses. One minor problem is that a 1/3" format lens has a very slight cutoff in the corners when recording in 720p, but most of my lenses are larger format.

-Eric
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Old Dec 30, 2009, 11:39 AM   #18
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Thanks for that Eric, it looks like it is in good hands.
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Old Jun 3, 2010, 11:07 PM   #19
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Default Best lowlight hybrid found! - Jaytech DVH24 (quick review)

I finally found a mini camcorder with really awesome lowlight performance. It is the Jaytech DVH24.

Info see here: Jaytech DVH24 quick review (great lowlight!)
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Old Sep 28, 2010, 10:04 PM   #20
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Default OmniVision security cam & Aiptek Sporty Cam

Although I got several other hybrid camcorders now, the DVH24 still has the best lowlight.

OmniVision mini security camera

My only thing that can beat it in lowlight is a tiny silver NTSC security camera (with OmniVision sensor) connected to the AV-IN of my Aiptek DV8900 (which internal image sensor is horribly dark and full of blue snow). It will certainly make a good point-of-view/helmet camera, although it is snowy and a somewhat blurred. I bought mine on eBay for 7.89 (1 + 6.89 shipping) but it turned out to be defective; the AC-adapter jack pin was bent and on the CDD was a very firmly sticking black dirt grain that looked like a rock in the picture. It took quite long to scrape it with a cable tie (do not use metal to avoid scratches!) and isopropanol off the tiny sensor chip (image area about 4mm) to get a rock-free picture. Also the 6 black IR-LEDs are fake - they are wired in series with no cable on their supply voltage solder pad, and their turned out to be duds (either no chip inside or faulty with interruption) with infinite resistance. (Working 3mm LEDs of any colour or IR can be easily installed.) Also the internal microphone makes beeping static noise (may be reduced by cable change). Regard that the voltage regulator (9..12V DC input to 5V internally) sits inside the black plastic piece that joins the 3 plug cables into one. The pcb contains a COB (black blob) IC as the main CPU and an 8 pin IC "24C16, 577641024" with MQ or QM logo like on Ouda toy keyboards. The case is of genuine aluminium.

The IR blocking filter is a tiny square glass plate on the back of the objective. By installing a different 12mm security cam lens without that filter you get a brighter picture in all funky alien colours. (E.g. the black felt front of my hifi loudspeaker boxes turns white!) The objective threads is coated with a nasty viscous grease that likely should secure it against vibrations. I removed it with isopropanol + Q-Tip because it is like designed to cloud the image sensor once it gets where it shouldn't. Unfortunately a 180 fisheye lens for dome cameras doesn't fit because its threads is too short to get a sharp image.

Apparently camera variants in NTSC, PAL and BW exist, with and without working IR LEDs. The security camera looks like this.

Aiptek Sporty Cam

Also the original Aiptek Sporty Cam AV-1 for the DV8900 has fairly good lowlight, although it overdrives bright image parts into white by too high output level (a resistor in the video cable can reduce this).

Regard that its semi-soft plastic case is awfully flimsy and its rear battery lid hangs on tiny plastic hooks and can easily fall off. (For a sport camera I consider this a bad joke!) Also the decorative blue plastic ring (apparently a misunderstood seal ring of a waterproof action camera that the Chinese designer tried to imitate) is flimsy and falls out every time you change batteries. Even inserting the 2 AAA batteries wrongways (can easily happen in the dark; both contacts look the same) would even destroy the electronics by the lack of electrical or mechanical protection.

To open its case, remove the tiny screw in the battery compartment and then insert a cable tie into the lens hole to pull out the bezel disc around the lens. Then push with fingers on the optic unit to slide the electronics out to the rear end. Do not pull at the circular plastic frame around the battery holes (like I did); it is way too flimsy and cracks apart when pulled or rotated by force. The optic PCB is plugged into the front of a main PCB that is not really smaller than the case (so removing it can not make it much smaller) and it is held only by a hotglue blob, that I consider too weak for an action camera.

- modification

The lens position is secured by hotglue, but when taken out or bezel disc removed, the objective can be turned by fingers to adjust focus. (It can see even a fingerprint in extreme macro when screwed all way in!) By peeling the foam rubber ring off the objective and sticking it to the inner side of the bezel disc, the focus can be even slightly adjusted by turning the installed bezel disc with 2 fingers by friction. You may also fit a mini security camera lens to increase sensitivity or view angle.

The electronics contains an inverter (kind of switching power supply) that increases the battery voltage to internal 4.5V or so that is fed to the image sensor and CPU. I discovered that holding a resistor of some 10 kOhm across a tiny SMD resistor near the rear end of the main PCB reduces the internal supply voltage by some volts (green LED turns darker, voltage depends on resistance), which makes the picture darker and removes the annoying scanline noise pattern in dark areas of the picture in lowlight. But a too low resistance drowns dark picture areas into black, so it would need to tweak the resistance very carefully to find the best value.

I instead simply soldered a tiny 1kOhm(?) trimmer into the video output line to reduce overexposed white areas. I managed to fit it into the tiny cylindrical camera case with screwdriver tweak hole on the outside.

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