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It’s a misunderstanding when people commonly say that focal length creates perspective effects. Perspective on landscapes and faces is determined by camera position and distance to the subject. It’s not even a camera issue — take a walk in the mountains. You see a boulder on the hill you are standing on and there is a distant mountain peak. As you walk closer to the boulder it gets relatively larger compared to the distant mountain. It’s the same thing with a face — get closer and the distance from your viewpoint to the nose changes but the distance from the nose to the ears is a constant, so the nose gets relatively larger compared to the ears as you get closer. What the focal length provides is the view of the subject, how tight or wide it is, the degree of magnification or expansion.
So if you match distance and you match field of view between formats by using the equivalent focal lengths, you get the same image more or less. What’s different is the depth of field, because the larger formats need longer focal lengths to achieve the same view, there is less depth of field unless you stop down the lens (by the same amount as the conversion factor, so if the factor is 1.5X then you’d stop down the equivalent lens on the larger format by 1.5-stops to match the depth of field of the smaller format.)
To calculate the equivalent focal lengths in terms of horizontal view, find out the width of the sensor area being used and divide the larger number by the smaller number to get the conversion (crop) factor.
Generic figures of 24mm wide for Super 35 and 36mm wide for Full-Frame 35 means you divide 36 by 24 to get 1.5. So that’s the conversion factor. To get a matching horizontal view you’d multiply the Super35 lens by 1.5 to get the equivalent view in FF35. So a 32mm lens in Super35 has the same view as the 48mm in FF35.
But to be more precise you need the actual widths of the sensor areas being used. Open Gate on a classic Alexa is 28.25mm and on the Alexa 35, it’s 27.99mm. Open Gate on the Alexa LF is 36.70mm. So if you were comparing a classic Alexa to an LF, both using Open Gate ARRIRAW, you’d divide 36.70 by 28.25, which is 1.3. So a 32mm lens on a classic Alexa would have to be a 41.6mm on an Alexa LF if you wanted to match the horizontal view.
There’s no right or wrong answer here. Some people want a clean image and will try to work at lower ISOs, others either want some noise or have to work in low light level conditions and will use a high ISO.
Surely whether a light looks moody at 10% or 100% is also a matter of ISO and f-stop chosen — after all, you can expose 10,000 foot-candles of full sunlight so that it looks like the .1 foot-candles of moonlight.
But you select an ISO and f-stop you like for noise & depth of field, then the light looks correct dimmed to 10% on your monitor/viewfinder, then what’s the problem?
When I was a beginner shooting on Super 8 film, I had one big light, a 650w open-faced tungsten made for Super 8 filmmakers. I did a short film on Plus-X b&w reversal, which was only 40 ASA and shot a moonlight scene using that light. Someone saw my short and said “wow, you worked in very dim light!” I was scratching my head because I worked in very bright light, it was just exposed to look dim.
If you are shooting digitally, you could try setting your camera to the ISO/shutter speed/f-stop you’d like to shoot at, turn on the LED lights at full, then by looking at an accurate monitor or your viewfinder if it has some exposure tools (zebras or false colors), start dimming the lights down individually until you like it.
OK, so three images didn’t work, I guess two is the limit.
Anyway, for the third time… I don’t think that chase scene in NCFOM is an example of day for night, it’s a night for night scene that goes into twilight for breaking dawn. The frames I just posted above are from “Yellow Sky” (1948), which has a lot of day for night shot on b&w infrared film by Joseph MacDonald. One artifact is that Gregory Peck’s black shirt goes grey due to IR pollution from the dyes in the fabric.
I typed a long reply and by the time I hit “submit” the website software didn’t accept it I guess! It disappeared!
I could use Google and find the links… but then I’d wonder why you don’t use Google and find the links!
The issue with a moon lighting effect is that IF you want it to coming from a backlit angle, can you get it high enough for your widest shot?
So you have to calculate that — getting something to raise a light very high may be more of a budget issue than what light you are using, which is also dependent on what ISO and f-stop you want to shoot at. With some digital cameras, a single Skypanel 360 would light a block at night for moonlight, and that can be powered through a household circuit sometimes, but can you afford an 85′ condor for example?
The primary purpose of the 2383 print emulation LUT isn’t to create a film look, it’s to work within a color space/gamut that works for both a DCP and a film-out so the movie would look the same in both versions. It’s less of an issue today with so few film-outs being done.
You have to start with what you want it to look like before you figure out what lights are needed. What effect are you creating outside the windows? Passing streetlamps? Passing lights from buildings? Moonlight? All of them? What light is on inside the bus? What colors do you want? What makes sense for the scene logically? Dramatically? Are you matching sources established in exterior shots? You have to have all those answers before you start talking about Skypanels versus Astera tubes.
I’d also say that if the backgrounds are going to be black, you don’t want to overdo a lot of passing lights from multiple places that can’t be seen, unless you dirty up the windows a lot with rain drops & dust, etc. so that the light washes out the black background. Otherwise if the interactive light gets too busy like the bus is in the city, you’d expect to see a view. So if this is more of a lonely country road or suburban street, there would probably be just passing overhead streetlamps, so given that there isn’t a lot of light outside the bus, it suggests that there are some interior lights on unless you are aiming for a very moody, shadowy scene, which is possible. It all goes back to painting a picture in your head as to how it looks before you can then figure out how to light it.
