We get asked all the time, "Why not just shoot Portra 800 in incandescent low light?" or "How is this any different than the technology of Portra 400?" Our response is usually something technical about the sensitometry of the blue emulsion layer and tonal curve, explaining the limitations of color correcting a negative when 1/3 of the color spectrum is underexposed. We love daylight balanced film, especially the amazing stocks that Kodak has released over the past few years! And for medium format under artificial light, Portra is our go to. The problem is having to expose daylight film as though it were a 200 speed emulsion, in order to collect enough of the cooler color spectrum (whether correcting in front of the lens or in post).
Here are Wirawan's test results (click images to enlarge):
This is the answer to why it's important to have a tungsten balanced film and not to "just shoot Portra 400/800 instead of Cinestill 800T", especially in tungsten lighting!!! For this test shoot I used tungsten balanced ARRI hot lights (350, 500, 600 & 1K). These are excellent professional continuous lights for anyone that is interested. The p800 is incredibly lacking sensitivity to tungsten light, even after I've added extra exposure to that film. It is my favorite film stock in very soft diffused light, especially on cloudy days, but it is not made for low artificial light. The p400 does much better, even pushed one stop to ISO 800, but how does it compare with CineStill in these conditions? Better you decide yourself!!" -Wirawan Sanjaya
|CineStill 800T beta test 120 rated at ISO 800 by Wirawan Sanjaya|
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