Iris & Gain Setting? at DVinfo.net

Richard Zlamany · June 22nd, 2007, 10:57 AM

Hi, I am editing a 3 cam wedding ceremony. When I was inputting the footage I noticed that one of the cams were set to 4.8 with 6 db. Is this a valid technique, shooting with such a high gain inside a church, when the iris could have been opened more?

Jamie Kehoe · June 25th, 2007, 01:25 AM

Hi Richard,
I have shot and edited a bunch of weddings in different surrounds and my opinion is if it is anything above 1.6 at full wide, then you shouldn't use any gain. It is better to be a little dark than too bright. Generally, so long as you have good contrast in the shadows and your bright areas are not blown out, you shouldn't ever need to use gain. Set the colour viewfinder to a mid level, not too bright or too dark. The eye viewfinder will always tell you the truth and you can use your zebra to check if the whites are blown out too much. The darkest church I have shot in required +6db with the aperture set (fixed, should always set it manual) at 1.6 fully wide to 2.4 full telephoto. Receptions are something else, but once you go toward +12db, you need to start using a camera light.

Craig Seeman · June 25th, 2007, 07:59 AM

Generally I'd open the iris before setting gain above 0.

There are times when one can set gain above 0 before adjusting iris.

Example:
Iris adjustments seem to be finer than gain adjustments.
Moving gain during a shot causes a noticeable bounce in luminance.
If I find I'm in a situation where some parts of the shot need to be gained up while others don't, I'll set gain to a given point and then adjust iris as needed.

Richard Zlamany · June 25th, 2007, 10:53 AM

Thanks for the input. The camera woman who shot this way is very experienced, so I can't understand for the life of me why she would do this. She must have made a mistake. If I get the chance I'll ask her.

Myron Iwankewich · July 6th, 2007, 08:23 PM

The gain allowed her to turn down the aperture. This gave her a grearer depth of field. Less hunting on auto focus and more leeway when in manual. The amount of gain she used adds next to no grain with that camera. I think she knew what she was doing

June 22nd, 2007, 10:57 AM	#1
Richard Zlamany Major Player Join Date: Jun 2005 Location: Hamden CT Posts: 470	Iris & Gain Setting? Hi, I am editing a 3 cam wedding ceremony. When I was inputting the footage I noticed that one of the cams were set to 4.8 with 6 db. Is this a valid technique, shooting with such a high gain inside a church, when the iris could have been opened more?

June 25th, 2007, 01:25 AM	#2
Jamie Kehoe Regular Crew Join Date: Jun 2007 Location: Brisbane, Australia Posts: 28	Not normally Hi Richard, I have shot and edited a bunch of weddings in different surrounds and my opinion is if it is anything above 1.6 at full wide, then you shouldn't use any gain. It is better to be a little dark than too bright. Generally, so long as you have good contrast in the shadows and your bright areas are not blown out, you shouldn't ever need to use gain. Set the colour viewfinder to a mid level, not too bright or too dark. The eye viewfinder will always tell you the truth and you can use your zebra to check if the whites are blown out too much. The darkest church I have shot in required +6db with the aperture set (fixed, should always set it manual) at 1.6 fully wide to 2.4 full telephoto. Receptions are something else, but once you go toward +12db, you need to start using a camera light.

June 25th, 2007, 07:59 AM	#3
Craig Seeman Inner Circle Join Date: Feb 2004 Location: Brooklyn, NY, USA Posts: 3,841	Generally I'd open the iris before setting gain above 0. There are times when one can set gain above 0 before adjusting iris. Example: Iris adjustments seem to be finer than gain adjustments. Moving gain during a shot causes a noticeable bounce in luminance. If I find I'm in a situation where some parts of the shot need to be gained up while others don't, I'll set gain to a given point and then adjust iris as needed.

June 25th, 2007, 10:53 AM	#4
Richard Zlamany Major Player Join Date: Jun 2005 Location: Hamden CT Posts: 470	Thanks for the input. The camera woman who shot this way is very experienced, so I can't understand for the life of me why she would do this. She must have made a mistake. If I get the chance I'll ask her.

July 6th, 2007, 08:23 PM	#5
Myron Iwankewich New Boot Join Date: May 2004 Location: Toronto, Ontario, Canada Posts: 20	The gain allowed her to turn down the aperture. This gave her a grearer depth of field. Less hunting on auto focus and more leeway when in manual. The amount of gain she used adds next to no grain with that camera. I think she knew what she was doing