Your ISO Settings Are Ruining Your Filmmaking

wasn't quite as clean as [Music] have you ever tried shooting a low-light dimly lit scene you exposed for the mood that you want maybe you bump up the iso a little bit but no matter what you do it always looks nice to a degree but then you look at movies like The Social Network or the Batman just to name two and they look freaking clean and it makes you want to throw away your dual native ISO camera because you bought it mainly for its low light capabilities but seriously how do we turn this into this how about we shudder some myths brace yourself because maybe everything you thought you knew about exposing to the Right iso low light and noise could be completely off track to begin it's crucial that we dismiss the notion that ISO directly affects exposure while it's true that ISO does have an impact on exposure the effect isn't really straightforward essentially ISO affects our Judgment of exposure but it doesn't alter the amount of light actually hitting the camera sensor the only two variables that truly dictate how much light will reach the sensor are the aperture of the lens and the shutter speed so to make the concept simple every camera has a sensor and that sensor captures light and turns it into an electrical charge that is then converted into a digital value the sensor has a certain dynamic range a camera applies ISO amplification to the signal after the signal is already been recorded by the sensor it doesn't actually alter how much light the sensor received in the first links so ISO doesn't really affect exposure but it buys us to expose a certain way I'll give you an example by making an analogy with audio recording imagine that you are an audio engineer and you're recording a singer and uh you make the headphones volume very loud this represents the iso given the eye volume you may be biased towards decreasing the input level of the mic and that represents the amount of light hitting the camera sensor so in this analogy you are under exposing the sensor and the opposite is true if the volume of the headphones is very low you're going to make the input level of the mic higher this recording is stronger level hence overexposing the sensor basically changing the iso value works like an amplifier we have a signal and we can either boost it or not but we can't change the nature of the synth note once it's been captured by the sensor so to demonstrate that ISO is just an amplification of the signal and not an actual increase of the light hitting the sensor I recorded a scene at three different ISO values 400 800 and 1600 without changing any other variable so the aperture of the lens and shutter speed remain the same all throughout and you could say well they look different Jimmy how can you say that ISO didn't change exposure I mean look at this yes but we didn't change the amount of light on the actual scene if we take ISO 800 as our reference for the two other ISO settings 1600 and 400 the camera just Amplified the signal more for ISO 1600 and Amplified the signal less for ISO 400 compared to ISO 800 and in fact if we adjust the three images to match the brightness level of the iso 800 image well they look exactly the same ISO 1600 isn't noisier than ISO 800 if pulled back by one stop and ISO 400 doesn't look any cleaner than ISO 800 if pushed by one stop that's because through these adjustments we've effectively made all three images as if they were shot at ISO 800. we basically changed the amplification of the signal in post instead of doing it in camera so with this out of the way how do we make our dark and Moody images cleaner well this is where exposing to the right comes into play exposing to the right means to give the sensor a healthy amount of light to work with but after everything we've said it should be clear that if you are exposing to the right by raising the iso you're not really exposing to the right you're just boosting the signal and in fact by erasing the ISL not only you're not exposing to the right but you're probably exposing to the left exposing to the right isn't a digitally bound practice if you ever shot film even for photos you probably heard the term thick negative exposing to the right is what you would do with film and what dlps did for a long time to get richer and cleaner images when working with film they would rate the film stock One Stop slower than nominal so they could print down a thicker negative to bring it back to normal exposure if you're confused I'll explain so if you have a 500 ISO negative you would meter it as if it was 250 so you would increase the light levels or open up the iris or a combination of both to expose for ISO 250 but you are actually recording at ISO 500 so you are effectively and constantly overexposing by exactly one stop then you take that Overexposed image and you bring it down by one stop in the printing process the resulting image will be cleaner and richer than the same image shot at ISO 500 and exposed for ISO 500 because by printing down or in digital by lowering the brightness of the image in posts you're not only making the image darker you're also pushing the noise floor down which will yield a cleaner image so the concept is very simple to get a clean image especially for Moody shots even if it sounds counter-intuitive you should have more light on the scene and to have more light on the scene you should use a lower ISO setting which is going to force you to compensate by actually using more light or by opening up the iris or by messing up with the shutter speed but that's going to change motion blur so mainly by increasing the light levels and opening up the iris on the lens that sounds great so the more I overexpose the more I can bring it down in post the cleaner the image that I will get yes but there's a catch because by overexposing or using a lower ISO you're sacrificing highlights latitude meaning that the highlights will clip faster but why is that it's confusing right why do we lose highlights detail with a low ISO setting well go back for a moment to the single recording example if we have a high headphones level the iso we're going to decrease the input level of the mic which is going to leave us with a lot of Headroom before audio clipping while if the headphones level is very low we're going to turn the mic level all the way up to compensate and the signal is going to be closer to the clipping point and it's going to eventually clip if there's a peak take a look at this I'm exposing for the gray patch here to have it always exposed at the same ire level and we also have a bright light bulb right next to it look what happens if we expose at ISO 200 400 800 and 1600 the exposure on the gray patch doesn't change but look at the bulb as we bump up the iso remember we increase the headphones level and we get further away from the clipping Point look how much more detail there is in the bulb if we expose at ISO 1600 compared to ISO 200 or 400. obviously we get more noise in the shadows but we also get a lot more information in the highlights because a high ISO level is going to bias you to underexpose the image thus gaining more highlights information so at the end of the day there's no magic here the camera it's always going to have the same amount of dynamic range and you're going to have to decide where you want the trade-off to be with some cameras changing the iso will change the dynamic range slightly but with most Cinema cameras this is not the case anyway you're going to have to decide where you want the camera to perform at its best do you want very clean Shadows by accepting to lose highlights detail or do you want to be able to get more highlights detail but more noise in the shadows what's the answer well it depends on the situation and on the type of scene that you're trying to capture if you're trying to capture a low light Moody scene where there's no super bright highlights or you don't care if they're clipped then lowering the iso will probably be a good choice very clean Shadows not much to recording the highlights anyway seems pretty reasonable to me the opposite might be true if you're shooting outdoor in a bright sunny day or you want to retain all the details in the sky during a beautiful sunset then raising the iso a bit will be super beneficial you will gain some Headroom in the highlights which you will need you'll also get more noise in the shadows but if the bulk of the image lives in the mid-tones and in the highlights then who cares I personally like shooting with my Sony fx3 at high cell 400 for low light scenes like the ones that you saw in the intro of the video and the 800 for daylight scenes where I can take advantage of the extra stuff of information and the highlights I personally never use the second native ISO of 12800 because it always looks unusably noisy to me that increase in sensitivity introduces what's called Photon shot Poise that is noticeable not in the shadows but more in the lower mid range which for me is very annoying so am I saying that high ISO settings don't have a usage for a low light situation well if you can control the amount of light that's actually hitting the sensor by opening up the iris or by increasing the light levels on set then it's better to do so if you can then bracing the iso to get an image that it's not Pitch Black is the only option you have and as technology improves you're going to be able to use high ISO settings without having to worry too much about noise so to sum it up remember that the iso setting that you choose doesn't really affect your exposure directly it affects how you expose your image I hope that I made the concept clear enough because um talking to people I realized that a lot of them were confused about this subject and if I wasn't clear enough feel free to ask any question that come in the comments down below I'll be happy to answer you and if you like this video well you know what to do please like share and subscribe and until next time

Channel: Jimmy on Film

Views: 738,247

Keywords: Cinematography, Filmmaking, ISO, Exposure, Low light

Id: RRIsYSC-EDU

Length: 10min 25sec (625 seconds)

Published: Thu Jun 29 2023