Gain Settings??Lost in grain!! at DVinfo.net

November 28th, 2002, 05:09 PM

Sorry to sound such a doofus but for out door shooting whats the best gain setting for my xl1s?
Because i shoot water light is always plentyfull all i want is the least noise/cleanest image possible,the cam came set at autogain but even in manual shooting mode the autogain still seems to do what it pleases,shouldn't mannual shooting mode make all settings lock until adjusted?
Does the 0 setting mean the gain is in essence Off?
I'm pretty confussed
Is there a kind soul out there who could give me an explination and maybe some suggestions?
Thanks

Adrian Douglas · November 28th, 2002, 08:05 PM

When shooting outdoors I always use -3db and a circular polorizer filter. Infact I use -3 when ever I can get away with it. This ensures a clean picture, with rich blacks and less chance of blownout whites.

0db gain doesn't mean "off" it just means that the electric signal is at a nominal level(whatever the factory set it at). Changing the gain either boosts of cuts this signal's power by whatever you set the dial to.

Jeff Donald · November 28th, 2002, 08:14 PM

If you are operating your XL1/s in the Green Box (all auto) mode the gain is adjusted for you by the camera. Change the operating mode (Auto, AV, TV, Manual) and the gain adjustment will be in manual and then you can adjust it.

Jeff

Andre De Clercq · November 29th, 2002, 09:15 AM

All CCD devices only output very small voltages (millivolts) So they need, apart from a number of other manipulations, to be amplified to get the .7 V video output voltage. This ref amplification (0db) can be changed depending on your needs. FYI "db" only expresses a ratio on a logarithmic scale and odb is 1 (20log *set ampl/ref ampl*=20log1=0). Zero gain would be *-infinite* db

November 29th, 2002, 01:56 PM

Thanks guys for the replies things are now a little clearer:)

November 28th, 2002, 05:09 PM	#1
Lee Evans Posts: n/a	Gain Settings??Lost in grain!! Sorry to sound such a doofus but for out door shooting whats the best gain setting for my xl1s? Because i shoot water light is always plentyfull all i want is the least noise/cleanest image possible,the cam came set at autogain but even in manual shooting mode the autogain still seems to do what it pleases,shouldn't mannual shooting mode make all settings lock until adjusted? Does the 0 setting mean the gain is in essence Off? I'm pretty confussed Is there a kind soul out there who could give me an explination and maybe some suggestions? Thanks

November 28th, 2002, 08:05 PM	#2
Adrian Douglas Trustee Join Date: Oct 2001 Location: Chigasaki, Japan. Posts: 1,660	When shooting outdoors I always use -3db and a circular polorizer filter. Infact I use -3 when ever I can get away with it. This ensures a clean picture, with rich blacks and less chance of blownout whites. 0db gain doesn't mean "off" it just means that the electric signal is at a nominal level(whatever the factory set it at). Changing the gain either boosts of cuts this signal's power by whatever you set the dial to. __________________ Adrian DVInfo.net Search for quick answers Where to buy? From the best in the business...DVInfo.net sponsors

November 28th, 2002, 08:14 PM	#3
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	If you are operating your XL1/s in the Green Box (all auto) mode the gain is adjusted for you by the camera. Change the operating mode (Auto, AV, TV, Manual) and the gain adjustment will be in manual and then you can adjust it. Jeff

November 29th, 2002, 09:15 AM	#4
Andre De Clercq Major Player Join Date: Sep 2002 Location: Belgium Posts: 804	All CCD devices only output very small voltages (millivolts) So they need, apart from a number of other manipulations, to be amplified to get the .7 V video output voltage. This ref amplification (0db) can be changed depending on your needs. FYI "db" only expresses a ratio on a logarithmic scale and odb is 1 (20log set ampl/ref ampl=20log1=0). Zero gain would be -infinite db

November 29th, 2002, 01:56 PM	#5
Lee Evans Posts: n/a	Thanks guys for the replies things are now a little clearer:)