Premium Member Max Jacoby Posted February 28, 2008 Premium Member Share Posted February 28, 2008 Are you saying that if something is white-clipped on the live monitor output, Post is somehow going to magically bring that back? If you test these data cameras you really need to put them through post to see what you can recover. Judging them by the live monitor output is like judging the dynamic range of film by looking at a print. Link to comment Share on other sites More sharing options...
Premium Member Keith Walters Posted February 28, 2008 Premium Member Share Posted February 28, 2008 Have you thought about using pulse width power for finer control of the brightness and linarity issues ? That was the first thing I tried. But unless you can sync the PWM clock to the camera's frame rate, you get unpredictable results. Also, what kind of ND's are you using ? I doubt they'd be super duper accurate for this kind of test...especially if it was lighting gel.jb Well in fact at the moment they are pieces cut from a Rep's sample swatch book! But I'm not depending on the accuracy of those, the "fine tuning" is done with the LED current. That's why I'm in the process of getting my cheapo llux meter recalibrated by a friendly engineer at a government lest lab. One reason I want to build an array of 15 LEDs is that I then only need to ensure that each LED is half as bright as the one next to it. For that I don't need absolute accuracy, since I will only be doing comparative tests. I still think smoked glass filters are the way to go though, since soot particles are chemically very stable. Link to comment Share on other sites More sharing options...
Premium Member John Sprung Posted February 28, 2008 Premium Member Share Posted February 28, 2008 Are you saying that if something is white-clipped on the live monitor output, Post is somehow going to magically bring that back? It there's white clipping on the video tap of a film camera, an experienced operator should be able to judge how bad it will be on the film, and unless it's really severe, Post production will as like as not be able to pull something out of it. The same thing most definitely does not apply with a video camera, as many a newbie operator has found to his cost. Maybe -- It depends on where the clip is happening. If it's the sensor that's overloaded, then no. Negative films have a lot of shoulder room, but data cameras don't. They're more like reversal film in that regard. -- J.S. Link to comment Share on other sites More sharing options...
Premium Member Keith Walters Posted February 29, 2008 Premium Member Share Posted February 29, 2008 Maybe -- It depends on where the clip is happening. If it's the sensor that's overloaded, then no. Negative films have a lot of shoulder room, but data cameras don't. They're more like reversal film in that regard. -- J.S. The only criterion for this test is: "get as many stops on the screen as you can". How this is achieved is up to the user, point is, if the sensor fails to capture it, it cannot be recreated. I want something accurate but not needing too much technical interpretation. Test charts and waveform monitors are fine IF you understand what they are showing you. Most cinematographers do not, at least in my experience. But they should understand a 15-stop array of lights on a black background. Link to comment Share on other sites More sharing options...
Nate Downes Posted February 29, 2008 Share Posted February 29, 2008 To clear things up tho, There are 4 gospels, 2 of which were supposed to have been written by actual Apostles. (Matthew and John). However theres is a question mark over who really wrote these. You're ignoring the Gospel of Thomas, which remains the sole gospel written during the time of Jesus' life, and in his own native tongue. Link to comment Share on other sites More sharing options...
Premium Member Walter Graff Posted February 29, 2008 Premium Member Share Posted February 29, 2008 You're ignoring the Gospel of Thomas, which remains the sole gospel written during the time of Jesus' life, and in his own native tongue. Actually ther is no proof of that and many scholars have different beliefs of who and when it was wirtten. http://en.wikipedia.org/wiki/Gospel_of_Thomas Link to comment Share on other sites More sharing options...
Adamo P Cultraro Posted February 29, 2008 Share Posted February 29, 2008 apocrypha don't count as gospels. Their authenticity is in doubt, which is why they never made it into canon. Link to comment Share on other sites More sharing options...
Nate Downes Posted February 29, 2008 Share Posted February 29, 2008 apocrypha don't count as gospels. Their authenticity is in doubt, which is why they never made it into canon. I'm not Christian, so to me, they all look the same. I suppose there are reasons for any of the books and such tho. Link to comment Share on other sites More sharing options...
Premium Member Keith Walters Posted February 29, 2008 Premium Member Share Posted February 29, 2008 Why does this thread about the authenticity of the RED keep turning into a thread about the authenticity of a religion? On second thought.... :-) Link to comment Share on other sites More sharing options...
Site Sponsor Robert Houllahan Posted February 29, 2008 Site Sponsor Share Posted February 29, 2008 apocrypha don't count as gospels. The gospel of Houllahan says: The first rule about religion club is that you don't talk about religion club. The second rule about religion club is that if you want to talk about religion club go make a movie about it and see if anyone shows up, you could get rich. Back to the Red camera: To me specifications only mean so much, a rough estimate of the camera but not descriptive on it's look or handling. People are shooting films with it now, right? films that have distribution attached, so soon everyone will see the result.... Furthermore I guess JJ talked a lot o junk at the beginning and now they're working on backing up the talk with something, it will not be the first or last camera ever made I assume they will get everything working at some point so it will be another camera out there after all the frenzy boils down and people will use it if they like it.. -Rob- Link to comment Share on other sites More sharing options...
Premium Member John Brawley Posted February 29, 2008 Premium Member Share Posted February 29, 2008 That was the first thing I tried. But unless you can sync the PWM clock to the camera's frame rate, you get unpredictable results. Well in fact at the moment they are pieces cut from a Rep's sample swatch book! But I'm not depending on the accuracy of those, the "fine tuning" is done with the LED current. That's why I'm in the process of getting my cheapo llux meter recalibrated by a friendly engineer at a government lest lab. One reason I want to build an array of 15 LEDs is that I then only need to ensure that each LED is half as bright as the one next to it. For that I don't need absolute accuracy, since I will only be doing comparative tests. I still think smoked glass filters are the way to go though, since soot particles are chemically very stable. I've done PW syncing with LED's ona film camera before (well i had one built) and i guess you could use the gen lock or a video output to do it, but if you make the PW fast enough, surely the camera wont *see* it ?? Keith if you need a lightmeter, drop me a line. I'm also shooting some RED stuff soon. Maybe we can test your rig... jb Link to comment Share on other sites More sharing options...
Radoslav Karapetkov Posted February 29, 2008 Share Posted February 29, 2008 Having not taken part in this thread for two days makes the interweaving of the RED discussion with the Christian one look extremely funny. :lol: RED crucify-ers should beware, cause even if they succeed in taking the cam's prestige down, it might very well come back.... stronger than ever before. :) Link to comment Share on other sites More sharing options...
Premium Member Keith Walters Posted March 1, 2008 Premium Member Share Posted March 1, 2008 I've done PW syncing with LED's ona film camera before (well i had one built) and i guess you could use the gen lock or a video output to do it, but if you make the PW fast enough, surely the camera wont *see* it ?? Keith if you need a lightmeter, drop me a line. I'm also shooting some RED stuff soon. Maybe we can test your rig... jb The problem is, once you get the clock rate fast enough so that the camera doesn't "see" it, the luminescent decay time of the LEDs starts to become a factor. Also, not all cameras have sync outputs available, including the RED and the Genesis. The great thing about DC driven LEDs is that they behave exactly like an incandescent lamp strobing-wise. From past experience, if you do a test that produces results that contradict the "orthodox" view of what results you "should" have obtained, people will immediately start picking holes in your methodology or equipment, and speculation about what might have caused the "error" rapidly becomes fact! Hence I have to be absolutely sure of my equipment. You can trust your light meter for set lighting, because a few percent error is not going to be of any consequence, but for scientific purposes, you are normally expected to independently calibrate your equipment, just to thwart any tendentious nitpickers :lol: I'll send you a private email about the other matter. Link to comment Share on other sites More sharing options...
Premium Member Keith Walters Posted March 1, 2008 Premium Member Share Posted March 1, 2008 To me specifications only mean so much, a rough estimate of the camera but not descriptive on it's look or handling. People are shooting films with it now, right? films that have distribution attached, so soon everyone will see the result.... -Rob- Not only that: At last, the first big-screen outing of a new digital cinematography camera will be on a reasonably mainstream feature film, not like some previous "Mail Order Bride" scenarios I could mention, where the first outings of new digital cameras were "franchise" productions that couldn't miss if they were shot on super-8 :rolleyes: But the REAL test, is how much repeat business the cameras get. So far the track record on this has been pretty dismal. Link to comment Share on other sites More sharing options...
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