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March 7th, 2008, 03:19 PM | #1 |
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Auto Gain Control
Is there any disadvantage to using Auto Gain Control?
I am practicing using Manual settings but seems that Auto Gain Control is working great, just not sure if there are times its a disadvantage. |
March 7th, 2008, 04:00 PM | #2 |
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I just finished filming an indoor event where the lighting from nearly every square of the building changed. I used the Auto Gain control indoors and found that I got a lot of noise in the lesser lighted areas and perfectly clear in the well lit areas. I'm not sure if there's something else I should be doing or not, but I was actually on the board just now to ask whether I did something wrong with my A1 to get so many shots with grainy marching ants when on auto gain control. It is definitely a weird look when I'm shooting a continuous shot as I'm walking and the people have snowy microdots of noise on them (usually dark clothes) and then when we get into a different (brighter) light situation, it clears up without a problem.
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March 7th, 2008, 11:40 PM | #3 |
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Uh
AGC will not adjust F stops, when using AGC, if there is really bright background light, your subject may becomes dark since the AGC compensate for the greater light source. Using AGC in variable lited areas, you may like to adjust F stop accordingly, ie, lower(open) F in dark area and increase(close)F in lited areas and let the AGC micromanages the finer detail of the amount of light; then again, refer to first part. Hope this help. |
March 7th, 2008, 11:48 PM | #4 | |
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Quote:
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March 8th, 2008, 03:33 AM | #5 |
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Using AGC (and forgetting it is on) is the number one reason people get bad video from XH-A1. You close the aperture to adjust the picture, AGC compensates adding gain and causing grain and noise.
Basic rule: never use AGC Advanced rule: after you thoroughly understand what each adjustement does and can not get results without using AGC, use it, but remember to turn it off! I have the gain set at -3, 0 and +3 or +6. Never higher. Underexposed looks better than the pulsating grid compression artefact I get from +12 gain produced noise. |
March 9th, 2008, 03:03 PM | #6 |
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Totally agreed, never use AGC.
set it up to -3, 0, +3 unless it really is dark and then push it up to +6 if you really need too. Jon |
March 9th, 2008, 03:26 PM | #7 | |
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Quote:
From first glance all the footage will be usable, I did shoot the second camera at +6 and not use AGC just kept everything close just in case the tripod mounted on AGC was too grainy. |
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March 9th, 2008, 03:46 PM | #8 |
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Hope the footage works out for ya.
J |
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