GS400 low light little enhancement at DVinfo.net

Etienne Sandre · May 10th, 2005, 01:02 PM

I was disappointed by the 18dB limit in the exposure gain in manual mode.

The "candle" mode in PROGRAM AE menu boosts a little bit the sensitivity, providing a brighter image than with 18dB in manual mode. No magic, you get some noise, but it may be useful in some situations.

Joshua Provost · May 11th, 2005, 04:21 PM

Are there cameras that do more than 18dB gain? None of the ones that I have used. Fortunately, the GS400 seems to have very little video noise, even with high gains. It seems rather smooth to me.

Josh

Boyd Ostroff · May 11th, 2005, 05:25 PM

Quote:

Originally Posted by Joshua Provost

Are there cameras that do more than 18dB gain?

THe "Hypergain" feature on the Sony HVR-Z1 gives you a +36dB boost...

Etienne Sandre · May 13th, 2005, 05:09 AM

If it has low noise even at max gain, means higher gains could be exploited and the limit has been set too low. Its is probably for marketting reasons that a 18dB limit has been set, to avoid the camcorder to be critisized as noisy.

Nightshot modes on sony camcorders do use a very high gain.

John Uchida · May 13th, 2005, 11:13 PM

Quote:

Originally Posted by Boyd Ostroff

THe "Hypergain" feature on the Sony HVR-Z1 gives you a +36dB boost...

For only about $3000 more :-), but of course it also does HD.

Yow Cheong Hoe · May 27th, 2005, 01:56 AM

The ratings +3db or +18db means nothing without refering to what +0db really is. On a super sensitive camera, let's say those $10,000 professional cams with large CCDs, +0DB cam capture at 1 lux, but on the MX series, +0DB captures at probably 50lux or so. So, +18db on the pro camera will make night shine like day (with the corresponding noise, of course) while +18db on the MX will be just nice to see what's in the house under two light bulbs, and with corresponding noise.

Going beyond +18db will probably show so much noise due to signal amplification that you'll not light the footage anyway.

BTW, my little contacts with the pro cameras tells me that sensor sensitivity is the key here: on a night street interview with only street lights, a pro cam can shoot at +3db to expose the face properly, but an MX will be under-exposing even at +18db and all the noise.

The other way to have more exposure is to run slow shutter speed, which some Sony semi-pro cams can. When shooting at 1/50 (I am in PAL-land) under-exposes, you can make the cam go 1/25 or 1/12 but this comes with streaking and blurs. Well, we need to evaluate what we want, sometimes, we MUST carry an additional light.

Guy Bruner · May 27th, 2005, 11:33 AM

Actually, 0 dB with iris at F/1.6 on the GS400 is about 220 lux. I really wish it were 50 (sigh)...

Yow Cheong Hoe · May 30th, 2005, 01:43 AM

Quote:

Originally Posted by Guy Bruner

Actually, 0 dB with iris at F/1.6 on the GS400 is about 220 lux. I really wish it were 50 (sigh)...

Ohhh... that bad... well, the alternative to these portable cams are the shoulder mounted not-so-portable cams that needs a van as support vehicle!

May 10th, 2005, 01:02 PM	#1
Etienne Sandre New Boot Join Date: May 2005 Posts: 8	GS400 low light little enhancement I was disappointed by the 18dB limit in the exposure gain in manual mode. The "candle" mode in PROGRAM AE menu boosts a little bit the sensitivity, providing a brighter image than with 18dB in manual mode. No magic, you get some noise, but it may be useful in some situations.

May 11th, 2005, 04:21 PM	#2
Joshua Provost Major Player Join Date: Sep 2004 Location: Phoenix, AZ Posts: 493	Are there cameras that do more than 18dB gain? None of the ones that I have used. Fortunately, the GS400 seems to have very little video noise, even with high gains. It seems rather smooth to me. Josh __________________ Owner/Operator, 727 Records Co-Founder, Matter of Chance Productions Blogger, Try Avoidance

May 27th, 2005, 01:56 AM	#6
Yow Cheong Hoe Major Player Join Date: Nov 2002 Location: Singapore, Passport: Malaysia Posts: 407	The ratings +3db or +18db means nothing without refering to what +0db really is. On a super sensitive camera, let's say those $10,000 professional cams with large CCDs, +0DB cam capture at 1 lux, but on the MX series, +0DB captures at probably 50lux or so. So, +18db on the pro camera will make night shine like day (with the corresponding noise, of course) while +18db on the MX will be just nice to see what's in the house under two light bulbs, and with corresponding noise. Going beyond +18db will probably show so much noise due to signal amplification that you'll not light the footage anyway. BTW, my little contacts with the pro cameras tells me that sensor sensitivity is the key here: on a night street interview with only street lights, a pro cam can shoot at +3db to expose the face properly, but an MX will be under-exposing even at +18db and all the noise. The other way to have more exposure is to run slow shutter speed, which some Sony semi-pro cams can. When shooting at 1/50 (I am in PAL-land) under-exposes, you can make the cam go 1/25 or 1/12 but this comes with streaking and blurs. Well, we need to evaluate what we want, sometimes, we MUST carry an additional light. __________________ Cam: Panasonic MX350EN, SOLD my MX8EN Mac: G3 400MHz PowerBook, 256 MB, OS 9 PC: Pentium 4 2800MHz, 512 MB, WindowsXP SW: iMovie, Final Cut Pro, Adobe Premiere, Ulead Video Studio, various little utilities

May 13th, 2005, 05:09 AM	#4
Etienne Sandre New Boot Join Date: May 2005 Posts: 8	If it has low noise even at max gain, means higher gains could be exploited and the limit has been set too low. Its is probably for marketting reasons that a 18dB limit has been set, to avoid the camcorder to be critisized as noisy. Nightshot modes on sony camcorders do use a very high gain.

May 27th, 2005, 11:33 AM	#7
Guy Bruner Major Player Join Date: Nov 2003 Location: Ashford, AL Posts: 937	Actually, 0 dB with iris at F/1.6 on the GS400 is about 220 lux. I really wish it were 50 (sigh)...