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-   Canon XL H Series HDV Camcorders (https://www.dvinfo.net/forum/canon-xl-h-series-hdv-camcorders/)
-   -   The real test - contrast ratios (https://www.dvinfo.net/forum/canon-xl-h-series-hdv-camcorders/57782-real-test-contrast-ratios.html)

Steven Galvano January 8th, 2006 09:26 AM

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

A. J. deLange January 8th, 2006 10:57 AM

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.

Steven Galvano January 8th, 2006 11:52 AM

Thanks for your insight.

How does this compare with previous HDV cameras such as the HD10 or FX1?

A. J. deLange January 8th, 2006 12:49 PM

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.

Dan Keaton January 8th, 2006 05:04 PM

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.

Matthew Greene January 8th, 2006 09:51 PM

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.

Gabriele Sartori January 9th, 2006 12:15 AM

ND Filter
 
Quote:

Originally Posted by Dan Keaton
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.

I just came back from 2 weeks in Asia where I used my old JVC HD1, the sky is not even the biggest problem, the biggest problem is when the sunlight hits directly objects, they are all white. The camera is amazing all things considered if it wasn't for this issue. To underexpose is probably the only solution but then we have another problem since one stop wouldn't be even enough. This is indeed my biggest concern on buying a new camera. I like the HD100 but at the end of the day each CCD is still 1280X720 @ 1/3" how can it be much better? Pixel saturation is pixel saturation and in the HD1-HD10 is VERY bad.

I'd like to know from people that tested the HD100

Regards
Gabriele


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