Minidv, lowlight shooting..Lux ratings?

[capman21]

I have a jvc minidv its on the low price scale, but it does the job. I do all my shooting inside and the vids are ok-good. Only problem is sometimes not all the time there is a lot of grain in the vids. Is there a filter for virtual dub that would help this? At camcorder reviews it rates my minidv at 3.75 for indoor shooting. I was looking at some minidv's that were over double the price what I paid for mine, and they were rated like 4.0. So in other words even the higher price cameras arent that great for indoor shooting it seems. Are there any minidv's that arent going to cost you at least a thousand that are good for indoor shooting? Also, is there a scale somewhere that tells you examples for lux ratings? Like 15 lux is compared to what?

[edDV]

Camcorderinfo.com puts a lot of effort measuring camcorder low light performance. It usually sorts by CCD size and the size of the optics (f stop). Idea is the bigger glass and bigger CCDs collect more light. Small camcorders with 1/6" CCD are the worse.

The broadcast guys use big heavy 3x (1/2" to 1") CCD camcorders with lenses that weigh more than consumer camcorders. Even then, they almost always use lights to get a good exposure.

[JohnnyMalaria]

Only problem is sometimes not all the time there is a lot of grain in the vids. Is there a filter for virtual dub that would help this?

The grain is by its very nature random noise caused by the thermal noise present in all semiconductors. Any filters designed to reduce the appearance of random noise will remove detail from the image.

The options are:

1. Open the iris more (if possible but it's probably already wide open)
2. Increase the exposure time - but once you get slower than the period of one frame, the video will start to look jerky/strobed
3. Cool the CCD with liquid nitrogen (!) - obviously not very practical. Very sensitive thermal imaging CCD sensors use a Sterling engine to get down to that kind of temperature
4. Use bigger sensors
5. Add more light

The above are what you can do at the time of recording. 5 is the more viable.

For existing recordings:

1. Average consecutive frames. This will create motion blurring but will reduce the random noise while maintaining detail in non-moving parts of the image. But, to decrease the amount of noise by a factor of two, you need to average 10 frames.

2. Apply a despeckling filter and/or smoothing filter - but you will lose detail

[rancid]

if i'm not wrong, LUX is the "unit" that is used to measure the lighting condition using candles... in other words, light source intensity of 1 candle...

for example, 1 LUX is 1 candle lit... therefore 15 LUX is 15 lit candles, the lighting condition equivalent to 15 lit candles, or 15 LUX...

someone correct me if i'm wrong...

[JohnnyMalaria]

Not quite.

10 lux = the amount of light from a candle that is 1 foot away (approx.)

See http://en.wikipedia.org/wiki/Lux (it's quite illuminating )

[rancid]

ok thanks !!...

i stand corrected...

[capman21]

Is it that the technology isnt there for consumer camcorders to produce very good videos at indoor low light settings.

[InXess]

majority of miniDV's are 7 lux and up. Some older models are 5 lux and 3CCD models like TRV950 were 3 lux. Even 5 lux camcorder is a rarity now (among lower priced ones). with smaller optical element comes usually smaller lens with relatively low brightness so most of cams are now at 10 lux and above. Sony stopped listing lux value for a lot of lower end cams as the values were totally unimpressive comparing to older models especially Hi8 or digital8. Semi pro cams (bulkier) have larger elements, cost more and perform adequately in low light.

[edDV]

Is it that the technology isnt there for consumer camcorders to produce very good videos at indoor low light settings.

The VX2100 (1 lux) is what you want. Maybe not what you can afford.
http://www.precision-camera.com/product/DCRVX2100

[jagabo]

You could use an 8 meter objective lens like the one at the Mauna Kea observatory and get really great low light videos. Your camcorder would be a little hard to carry around though.

[InXess]

The VX2100 (1 lux) is what you want. Maybe not what you can afford.
http://www.precision-camera.com/product/DCRVX2100

exacltly what I meant without naming it; excellent camcorder