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Exposure for HDV /DV


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#1 Edward

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Posted 25 August 2005 - 10:46 AM

Hello, I'm trying to figure out a foolproof method to get perfect exposure using my Sony HVR-Z1E camera - I have already asked a few people I know who just tell me to use the screen on the camera, however in the past this has sometimes let me down. I can't really carry around a monitor with me to check the picture so I have been playing around with zebras, auto iris etc. however I was wondering if I should invest in a hand held light meter? I have just bought a couple of Dedo 150w lights and a Lowell Rifa 500w light for filming interviews and I would like to know how to get a nice lighting ratio. Any tips? Thanks, Edward
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#2 Lars.Erik

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Posted 25 August 2005 - 03:07 PM

I wouldn't invest in a meter. I have one myself, but only use it when I'm rigging large sets. It gives me an idea of the f-stop, but more importantly, it gives me an idea of the lighting ratio. The final judgement I do with the help of a properly set up monitor and zebraes. The light meter will not be good enough for this when it comes to video. Becuase the CCD chip will react differently in different light situations. Besides, for your kind of work, it doesn't sound like it's worth the cost.


The screens on 1/3" cams, or 2/3" for that sake, is not very reliable in my experience. Your best guess is the use of zebra. I've used the new Sony HDV once. It need quite a lot of light compared to for example the DVX100a. It's about 1 1/2 to 2 stops more light sensitive.

But since I have limited experience with this camera, my best advice to you is to get a PROPERLY set up monitor, take the cam out with you and play around. Use the zebraes and see the result in the monitor. In this way you'll be able to learn how the zebra should react to the pictures you want.
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#3 Edward

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Posted 26 August 2005 - 04:03 AM

I wouldn't invest in a meter. I have one myself, but only use it when I'm rigging large sets. It gives me an idea of the f-stop, but more importantly, it gives me an idea of the lighting ratio. The final judgement I do with the help of a properly set up monitor and zebraes. The light meter will not be good enough for this when it comes to video. Becuase the CCD chip will react differently in different light situations. Besides, for your kind of work, it doesn't sound like it's worth the cost.
The screens on 1/3" cams, or 2/3" for that sake, is not very reliable in my experience. Your best guess is the use of zebra. I've used the new Sony HDV once. It need quite a lot of light compared to for example the DVX100a. It's about 1 1/2 to 2 stops more light sensitive.

But since I have limited experience with this camera, my best advice to you is to get a PROPERLY set up monitor, take the cam out with you and play around. Use the zebraes and see the result in the monitor. In this way you'll be able to learn how the zebra should react to the pictures you want.

<{POST_SNAPBACK}>


Thanks Lars, any tips on using the Zebra? I have had people telling me to set it to 70, 90 or 100, but I think that it is probably more important to know how much zebra you can get away with in the picture rather than which setting to use. One problem I get is where there is a bright light or sunlight to one side of the subject and then I end up with one half of the face over exposed and the other half under exposed (a poor lighting ratio I guess) - without a monitor with me it would be nice to know when this is a danger so I can use a reflector or light to provide the correct fill.
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#4 Lars.Erik

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Posted 26 August 2005 - 08:02 AM

If you have bright sun on one side of a persons face, with no or little fill on the other side, then your pictures will ALWAYS be either over- or underexposed. This is how video works. It's the limitations of the medium of videotape, not the camera. Film will also work this way, but they have a higher lightning ratio than video. Video will be around 4:1 - 5:1. Anything over that, and you will lose details in the whites and blacks. Specially when it's for tv. Film can in some cases have all the way up to 9:1. Film noir for example have a very high lighting ratio.

When shooting on a sunny day, you will either need HMI's or reflectors to fill the dark areas. You can either use use white reflectors, which is common, these should be no more than 5-6 feet away from the subject. (Depending on the size of the reflector, the bigger the reflector, the longer away it can be). You also have silver reflectors, which are great if you need them further away than the above mentioned. These will give more light. And you have gold reflectors, I've never used them, because they are very intense. Lastolite are good and easy to carry around. Just be careful to use them on windy days, as the moving reflector will make the light move around.

Zebra: 100 IRE is the broadcast safe for this cam. It means that the brightest spots in your frame should have zebraes in it. Windows, lights, bald head with highlights on it, the hot spots of a car or a snooker ball etc. Personally I use 90 most of the time. Meaning that your subjects face should have a little more zebra in it than at 100. For example, a little on his forehead. (From where the key is coming from)

70 is the correct skin tone IRE, this means that most of your subjects face should have zebra, I don't use this function as is make it difficult to judge focus.

But most importantly is that you also see with your own eyes that the lights hitting your subjects face isn't to harsh. In time it's easier to judge this. So use fill lights to do this.

One can also have the subject with it's back to the sun, this will create a nice kicker. But you MUST use a reflector then.
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#5 John Pytlak RIP

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Posted 26 August 2005 - 08:31 AM

Modern color negative films have tremendous latitude compared to digital capture. FWIW, the AVERAGE brightness range in a scene is 160:1, but many scenes may exceed 1000:1.
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#6 Lars.Erik

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Posted 26 August 2005 - 08:59 AM

Yes, sorry. Got it backwards. Ratio of 5:1, I really meant 32:1, meaning a 5 f-stop difference.
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Aerial Filmworks

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Abel Cine

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Tai Audio

Ritter Battery

Rig Wheels Passport

Broadcast Solutions Inc