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January 8th, 2006, 09:26 AM | #1 |
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The real test - contrast ratios
I am thrilling with the evolution of camcorder in recent year.
i was among the first to own JVC's HD10 and shot a feature documentary in Kenya with it in November of '03 (http://sgww.org/kenya) Early last year I purchased the Sony and there was a realizable difference. The real limitation of these cameras versus film or a broadcast HD camera (such as the Sony 900) is contract ratios due mostly to small chip size and lens limitations. Any time I used the JVC outdoors if I wanted any kind of color in the sky outdoors, everything else would be underexposed. If I wanted to properly expose a exterior day shot, the sky and everything else whiter then my subject was blown out. The Sony handles ratios much better than the JVC. Is the canon a large step forward? In some initial still tests, although the resolution is noticably better, the sky looks blown out to me. Thanks Steven Galvano Colors Studios |
January 8th, 2006, 10:57 AM | #2 |
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In testing with the Putora chart I find the gray scale easily fits within the dynamic range of the XL-H1. The gray chips span .03 to 1.72 density on that chart and thus the camera demonstrably has dynamic range of at least 5.7 stops. Film, conversely, has about 7 (thinking of Ansel Adams' 9 zones with zone I being detail-less black and zone IX being detail-less white) but film will allways have the advantage that detail can often be teased out of over exposed areas whereas a blown highlight from an electronic sensor is blown - period. My philosophy, thus, is to set the zebra stripes for 100 and use the maximum exposure that they will allow i.e. you look in the EVF and if more of the picture than you wish to be blown is in zebra stripes you back off until the striping just disappears or is only in places where you can tolerate a specular highlight. If I want a nice deep blue sky I may intentionally underexpose (according to the meter) and then tweak gamma in post. The situation with electronic images in dark areas is just the converse - you can often tease some detail out of them.
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January 8th, 2006, 11:52 AM | #3 |
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Thanks for your insight.
How does this compare with previous HDV cameras such as the HD10 or FX1? |
January 8th, 2006, 12:49 PM | #4 |
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I've never had my hands on any HDV camera other than the XL-H1. I'd expect the results to be about the same as CCDs in general behave in this way both in still and video cameras. I did see similar results with the Canon XL2.
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January 8th, 2006, 05:04 PM | #5 |
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Dear Steven,
Using a graduated neutral density filter to compensate for the overly bright skies, while maintainikng proper exposure on your subject, can be very helpful.
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Dan Keaton Augusta Georgia |
January 8th, 2006, 09:51 PM | #6 |
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Well, a 1/3" sensor isn't going to offer the dynamic range of a larger sensor or film, it's just physics. You just have to expose and light correctly because you can't get overexposed information back with video as well as you might be able to with film, which has a little room.
A.J., you mentioned that film has about 7 stops of lattitude, maybe when telecined but I usually have no problem getting 8 to 9 stops of lattitude with Vision 2 stocks. Of course, all this lattitude doesn't make it to the screen but it allows more room to compensate for over/under exposure in post. |
January 9th, 2006, 12:15 AM | #7 | |
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ND Filter
Quote:
I'd like to know from people that tested the HD100 Regards Gabriele |
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