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#1 David Bradley

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Posted 01 March 2007 - 10:17 AM

I have always assumed that since the minimum sensitivity of video is 7.5 IRE units, the three little bars (pluge bars) on the SMPTE bars are arranged as 3.5, 7.5 and 11.5. Since 7.5 is maximum black then surely there should be no difference to the eye between 3.5 and 7.5 and they should both appear fully black. Only 11.5 should be discernably different to the 7.5 units.

My problem is I constantly appear to over expose with a 'properly' lined up monitor or viewfinder. As a result I tend to set my montior brightness slightly higher than it should be and expose to that. Can some one tell me where I'm going wrong because work have mentioned this slight over exposure on several occassions now and I never find out until I hit capturing.

Edited by David Bradley, 01 March 2007 - 10:19 AM.

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#2 Brian Drysdale

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Posted 01 March 2007 - 11:17 AM

You also need to set the max level using the white box to the left of the pluge adjusting the contrast control so that it just bleeds into the adjoining area. Also make sure that the monitor is correctly terminated.

Using the zebras or a waveform monitor will give you a more exact idea of the exposure levels.
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#3 Michael Nash

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Posted 01 March 2007 - 12:58 PM

Be careful of the viewing conditions of the monitor as well. Excess ambient light hitting the screen can make the image appear duller than it really is, sometimes making you want to open up the iris to compensate. Check the monitor image with all the room lights off, or with a hood over the screen when in bright conditions.

If you know you're prone to overexpose, then concentrate on getting proper midtones and highlights -- don't worry about the deep shadows.
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