View Full Version : HD(V) and filmout
Radek Svoboda July 3rd, 2005, 05:44 AM Films that were made made in HD that had decent picture all had high contrast. Ones I refer to are Once Upon Time in Mexico, Star Wars Episode 3. If there is lot lattitude, which means lower contrast, picture just does not look as well. Did anyone else notice? Is this how HDV has to be shot? Do you have to crash blacks to get decent picture for film out?
Radek
Wayne Morellini July 10th, 2005, 08:00 AM It is an optional choice wherever the film is contrasty or low contrast. You will notice that most pro films prefer the low contrast look (Xfiles for an example) it gives a very subtle warm (though not talking about colour) mood. They also prefer higher saturation colour in combination within this.
The problem with CCD video is that it has limited latitude, so you have very little option but contrasty, or using ND filters (which I believe squash the blacks). In film you want mainly one shutter (accross most films) and you want narrow Depth of field. So all you can really play with on Video is lighting, gain and ND.
With previous generation of CMOS (last years batch) I think you could get better latitude than many CCD but not as good as using film. But with chips using the dual slope/Autobrite feature (which I think this camera may use) you can get very good latitude close to (or more than) film. This is only a 1/3inch chip, imagine a bigger 2/3inch+ sensor.
Ken Hodson July 10th, 2005, 11:05 AM "But with chips using the dual slope/Autobrite feature (which I think this camera may use) you can get very good latitude close to (or more than) film."
Wayne what camera are you refering to?
Charles Papert July 10th, 2005, 11:38 AM I would not necessarily equate latitude with contrast. To me, gamma and toe are the more directly connected with contrast, and that has to do with the angle of the exposure curve rather than the number of steps inbetween. Imagine a perfectly exposed interior scene with a blown out window (say four stops overexposed) shot on digital; now imagine that same scene shot on 35mm, where some detail is held in the window. That's a function of latitude, not necessarily of contrast.
A good filmout process will effectively stretch the whites and blacks of the video image to the corresponding points on the filmstock, creating more contrast than might be seen in the original video footage.
Wayne Morellini July 11th, 2005, 02:31 AM Ken,
The HC1`, though I don't know how good it's scheme is compared to the sensors made by smalcamera and fillfactory (go to their websites and you will see sample pages/docs). It is not a perfect technology, you will notice that the colours response is different depending on wherever the exposure is being brought down or up.
www.smalcamera.com
www.fillfactory.com
Charles,
As I guess you probably know, gamma curve is a trick to mimic natural like response curves. Vision and film stock perform differently on different intensities. The result is that the latitude is compressed by this. In video they normally have a more linear response increasing in sync with increasing brightness. To simulate gamma curve they use a higher bit depth (say 10bit) on video and squash it down into a 8bit gamma curve to get 8 bits.
In video, gamma from linear makes the video look more natural and more natural at less bits, but doesn't increase the latitude. In film, and vision, however gamma curves causes a compression of latitude.
So gamma curves cause a more natural looking contrast/tonality, but latitude (and Signal to noise ratio) still determines the difference between the darkest value and saturation point of the brightest value, the contrast. I don't mean bit depth in regards to latitude but range of actual intensity.
Ken Hodson July 11th, 2005, 11:35 AM Radek -"Films that were made made in HD that had decent picture all had high contrast. Ones I refer to are Once Upon Time in Mexico, Star Wars Episode 3"
Wayne -"The problem with CCD video is that it has limited latitude, so you have very little option but contrasty"
Wayne -"using the dual slope/Autobrite feature (which I think this camera may use(HC1)) you can get very good latitude close to (or more than) film."
So what you are saying Wayne is that HD cams used in these high budget movies have less latitude than a HC1? You can't be serious?
Jack Zhang July 11th, 2005, 02:03 PM Soon they've got to come up with a 3CMOS system!
Barry Green July 11th, 2005, 04:49 PM Soon they've got to come up with a 3CMOS system!
JVC is planning to use 3 CMOS sensors in their forthcoming 2/3" GY-HD7000U camera (but that's a whole different price league; $27,950.)
Wayne Morellini July 11th, 2005, 09:53 PM Ken
I don't know for certain, but totally serious, totally possible compared to the original CCD HD cameras, which were known for latitude problems. Now situation is much better (Star wars Episode 3) but cmos better, and dual slope better again. Once upon a time in Mexico is a contrasty film, I would say at the limits of what you want, but that also has to do with latitude. I can't remember, but look at the shadows, if you see lots of black, and especially with lots of burn out in the highlights, definitely latitude limitation. You can fit higher latitude in a low latitude camera in by ND filters (or use lighting to lower the latitude) to reduce the contrast of what is hitting the CCD.
The truth is, that when you are pushing the limits you get stuck with one look, contrasty in moderately contrasty situations. In post people can push around the image also to make it look better, or hide the limitations, particularly by pushing colours up (which the old HD cameras did internally anyway).
Thanks
Wayne.
Wayne Morellini July 11th, 2005, 10:00 PM Soon they've got to come up with a 3CMOS system!
You can get one from Sony today, but only in the SD 1000.
If anybody is serious about low end digital Cinema shooting, go and look over at the cinema threads in the alternative imaging section, for projects that are serious over there. At the moment only the Drake people are too market with a dual slope camera, and other things planned, possibly cheaper. There is company called Sumix planning a cheap single chip 1080p Altasens camera (as the new JVC 27K is going to use, for a fraction of the price). But none of there cameras are point and shoot, but more the size of a film camera, or large shoulder mount. We asked the question, what about Hard drive capture of uncompressed component out for the HC1, but nobody wants to take it on. Things are a little cinema elitist, and many people aren't interested in, low end point and shoot solutions.
Hdforindies.com is also a good resource.
Radek Svoboda July 12th, 2005, 04:38 AM High contrast of digitally made films is due to recording systems limitations, not due to CCD limitations. You have quite wide lattitude on CCD before you have to use ND filter.
Low contrasty pictures like Episode 2, Russian Arc just did not look good, did look awful.
What my original question was: how shoot with FX1E for highest quality film out? Should I crash blacks, go rather for linear light response?
Spy Kids 2 had very saturated colors. Is this what is needed to make digitally taken motion picture look the best?
I'd rather compromise color, contrast than have some ugly image like Episode 2 or Russian Arc.
Radek
Wayne Morellini July 13th, 2005, 11:22 AM OK, I see, misunderstanding your question and which camera (thought you were on about the HC1). I'm assuming you are talking about Indie film here, trying for a more polished big budget look. I've already written most of the following so good read anyway (my apologies, too late not thinking straight). Film out, are you talking about component again, don't have a Sony FX1?
Yes, too much latitude does make a picture overly murky. What they try to do is have a acceptable range of intensity to look at. You will notice that a lot of films seems to have the lighting of a cloudy day, with little hi-light and good subtle range of tonality, and shadow detail, more comfortable too look at. While some films seem to have the lighting of a moderately bright day, and the tonality is stretched (high contrast) and if the main character is dying of thirst in the desert and delirious, they seem to have the disorienting look of a very bright day. Some extra colour (not PD150 style) make the film look better, so HC1 is good there, but if you want to really dramatise things extra colour (like Spykids and low numbered Starwars films) canbe used. The maximum brightness of white canbe set lower to dull the film. I expect the FX1 to have less latitude be higher contrast, need ND and have more squashed blacks (but much better low light) than the HC1. But with HC1 you maybe able to adjust footage more too taste to look like the FX1. I think extra color also jazzes up low contrast images. That pretty much summarises most of the bits below on your question.
On the issue of the component out. If all goes according to plan and SN allows 10+ bit of resolution, definitely finale to gamma (not linear) the extra bits will help. Use it too your advantage to get the purest colour/luminance values, and do all else in post, such as squashing blacks.
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Don't be folled, by adromeda related interpretations. Sure it reveals an extra couple of stops information (that's if the SN ratio is high enough to make it ussable) but basically 10 bit CMOS camera has the same advantgae pluss whatever extra stops it had in the fist place. It doesn't really change the fstop range, just reveals extra iunformation if the niose is low enough.
Russian Ark was suitable, Episode 2, I think it was made to look low contrast, but still has the look of a high contrast picture underneath in places, just dimmed down.
To answer your question, with an opinion, I advise seeking out people like Jaun in the Digital Cinema threads who is pro color corrector. Is that with higher latitude you have more quality to play with and it should be easier to, effectiuvely, convert it to high contrast post rather than get high contrast to look low contrast. I like it pretty much close to as is, color, and lighting wise (I would use IR (and UV/skyblue filter) to make sure that the mild washout I observed in some shoots is reduced). But whatever is your taste.
Extra colour sensationalises your film, hypes it up, you can say. I was watching a funny local comedy last night, called "A mans gotta do" or somethign like that. I looked at the special features doco after and noticed that the colour rich Panavision film footage (apart from low contrast that they do to relax the audience) was probably less than half the saturation and contrast as the video camera they were using (I think I saw somethign like a PD150/Pana 100). So the colour level on the HC1 is probably more professional than that of the PD150, and most minidv cameras.
On squashing the blacks, there is a loit of detail in the balcks and the highhlights on this camera, good, do it whatever way you like the effect.
This is the sort of quality I see in many big budget films, because they want perople to be fully relaxed and enjoy themselves, in their cinema experience. But, of course, if you want an exciting dramatic action film you go for brighter high contrast look with extra saturation (like one of the Spy Kids at least). Take the pop, bang, wiz, candy store image to the kids. If you want a dark erie tech look squash the blacks a bit (actually a little black squashing probably would be good in either catergoy of film look). But if you have a low latitude camera than the high contrast image, and squashed blacks with reasonable highlight defintion might be the only viable look. Witht he HC1 I think you have option to do both. In Collaterial the Sony footage was less desirable than the less contrasty high end Viper footage (actually look at Startship troopers Two as well). Now go to the Drake camera thread and to the sample footage at there site. The sensor has much more potential than displayed on the prototyped camera, and the footage is a dream sequence so it was meant to be very dim and murky with little colour. Now turn all the colour settings up in your player/card and notice that the image comes alive, so you can do a bit with high latitude image. But one thing I notice, is that in the dull low contrast film, the brightest white might be half the perceptual brightness of the bright high contrast film, the image is actually squashed down in contrast (but as I said seek an expert opinion). For older veiwers and sick people like me, an image that is too bright and high contrast (apart from looking out of balance and unatural) actually can cause pain to look at, because our eyes can only cope with much less lattitude and brightness shifts. So films for older adults tend to be lower contrast and concentrate on thought and emotion rather than action. Anyway, I think, you can push around high latitude image to get different looks (but I think you need more bit depth to use it effectively, as eventually you will get stepping in an image, so tehre must be some hard and fast mathematical rule between the number of extra bits required to push the image x number of stops). This explains a lot about the range of film styles, pick yours for your film style.
Was that the sort of information you were after?
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