Carsten Kurz
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Oops, my fault again ;-)
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Daniel, never mind, we speak of one and the same thing in different words (assumptions not mentioned explicitly).
What do ADU and HTP mean?
That explains it; I should have suspected that sooner. :smile: Thanks, Lauri.
ADU means Analog to Digital Unit. It's another word for "raw level", quantization step, or Digital Number (DN). It's the value that comes out of the Analog to Digital Converter (ADC). Each pixel in a 12-bit raw file may be from 0 to 4095, the number is the ADU.
HTP is Highlight Tone Priority, which is Marketing Speak for ISO metadata. Unfortunately, Canon botched their ISO implementation (like they did with many other things), throwing away at least 1 or 2 stops of dynamic range at over half the ISO settings for no reason (except to needlessly bloat the file sizes). I'll never understand why Canon pairs brilliant sensor designers with such incompetent software engineers. Hanlon's razor, I guess.
ISO 320 is better than the old 320!
Really, if you feel uncomfortable using the iris on your lens, or filters, or a "single speed emulsion camera" (I've never heard of a multi-speed emulsion) you'd better find another game, regardless whether your ideal camera has 9 or 14 stops.I, too, still feel a bit, err, confused. We have a R1 camera with 9-11 stops of latitude, depending on how you measure. No usable analog gain, but then clearly a sensor with a fixed sensivity to light (photon efficiency, whatever you call it). That means, if you want these 9-11 stops of DR to be captured - you have a very limited range of lighting conditions to achieve this. One, to be exact. You achieve that DR only at a sweetspot. Which is very different from using different filmstocks, and from using cameras with (useful) analog gain.
In technical terms, shutter speed, stopping up/down, NDs, changing lights, are options, but in practical terms, they can only be used in a very limited range or not realistically at all. If that sensor had 14 stops, it would be less of a problem since you could still have a decent range even with high levels of under/overexposure.
I know this is not a real issue with most big budget productions where you simply book the necessary amount of light. For other shooting types, I still feel a bit uncomfortably with that idea of having only a single speed emulsion hardwired in the camera.
- Carsten
We have a R1 camera with 9-11 stops of latitude, depending on how you measure. No usable analog gain, but then clearly a sensor with a fixed sensivity to light (photon efficiency, whatever you call it).
That means, if you want these 9-11 stops of DR to be captured - you have a very limited range of lighting conditions to achieve this. One, to be exact. You achieve that DR only at a sweetspot. Which is very different from using different filmstocks, and from using cameras with (useful) analog gain.
Really, if you feel uncomfortable using the iris on your lens, or filters, or a "single speed emulsion camera" (I've never heard of a multi-speed emulsion) you'd better find another game, regardless whether your ideal camera has 9 or 14 stops.
I think there is great confusion about what "rating" the camera means. To some it means that's what they set their meter to, light for, and set the lens stop to. For others, it means changing the camera's metadata to 320, 500, etc. And to others it seems to mean doing both of these things. Everyone seems to use the term differently around here from what I gather. Not sure if it's knowingly or unknowingly. Changing the camera to ISO 500 and exposing using false color is not, in my opinion, really "rating" the camera 500 because if you exposed the same scene using your light meter at 500 you would end up with a very different result.
*My light meter was manufactured by the Sirius Cybernetics Corporation, BTW.
Will a Red One with the upgrade to Mysterium X sensor be able to achieve the same frame rates as the Epic?
If I set my ISO to 100 on a normal sunny day outside, lens to 5.6 and shutter to 1/48, my light meter will probably say "good job," and the false color will probably show a nice tonal range. But if I set my ISO to 1600, my light meter will probably say "holy crap, stop down or put some NDs on or something, you crazy bastard*" and the false color will be mostly, if not all, red. In either case, I would stop down or put NDs on, which would produce the same result, right?