Understanding Contrast Ratios

[@ZachBoyce]

This is actually one of the most helpful lighting tutorials on using a light meter for video purposes, on youtube. Surprised it doesn't have more views or likes.

[@vistek]

Zach, thank you very much! Super appreciate the comment!

[@pragmaticapproachenglish6875]

i agree really

[@thecreativeclass1276]

I’ve had a light meter for two years and this helped finally figure out its usefulness. Thanks.

[@vistek]

I’m thrilled to hear this! Contrast ratio control is one of the best uses of a meter.

[@steadihut]

Really well done!!! Not only clear and to the point but by showing the relationship of Key to Fill, back light and back ground you've put together whole picture! Thank you!

[@vistek]

Thank you Mark!

[@twinpalmsvideo2741]

Wow, I just went from stoopid to "Film Maker- Level 1 " This was so clear and easy to understand. Thanks.

[@vistek]

Thanks TPV!! 🙏🏼

[@SuchetB]

This one of the best light meter and lighting videos I’ve seen - thank you ⛩

[@vistek]

Thank you Suchet!!

[@DebashishKumar123]

Your key light is such a massive source that it is wrapping around the face so much that it is killing the contrast

[@vistek]

I agree a bit. But we have such a small space to work with it's hard to do anything but what I did in there. That said, I mostly (and very politely disagree) as I was able to achieve every contrast ratio to near exacting amounts. Maybe you would have prefered to use a hard light source to make the examples stand out more. The reality though, is that in real would scenarios we are having to manage contrast ratios with very soft light sources. Especially those on female actors or models. So I still feel confident that my example represents a realistic real world example. However, i really appreciate the comment!

[@scarlettstoever8093]

@@vistekhow do you recommend keeping the key light from wrapping around too much, how are you controlling the contrast? I have the same issue, a teeny tiny space and a huge key light.

[@Greego]

This is an outstanding video. It’s done with the heart of a teacher and I really appreciate that.

[@vistek]

Thank you so much! It was done a long time ago in a cramped space. I'm intending on re-doing it - and making it classier. But it's got a lot of views, so I'm not sure making it again is worth it.

[@Greego]

@@vistek I definitely understand the high standards. However, whatever limitations you perceive in it, it accomplishes its mission very well. I’m not sure what else there is to improve on besides any aesthetics from improved technology but, if you do redo it, I think it would probably be for the fun of it. Otherwise, it is excellent. 👍

[@anthonypc1]

MOST helpful explanations I've heard. And I'm not new to cinematography even...

[@vistek]

Thanks Anthony!

[@bdawg6900]

Hi sir, thank you so much for explaining how to calculate contrast ratio. I am wondering at 3:16, the light meter reads F8.09. Why is this closer to a F11 instead of a F8.0? Thank you

[@littlestream80]

I would really like to know this as well

[@vistek]

Sorry I missed this comment from three months ago Bdawg. The answer is because the numbers after the decimal are a 1-10 value. In fact 10 doesn’t exist, because 8.10 would be f11. So 8.09 is just under f11.

[@thepipethefilm]

@@vistek Thanks for that - I wondered that too and never realised what that number after the f stop was!

[@theyirum5501]

wow......Thank you. this is such a big value. Clear and easy.

[@just.do.something]

Hello, thanks for the video. It was greatly informative. My feedback would be the key light has too much wrap around to the fill side. I do feel this video would be better demonstrated with more contrast between key and fill. Anywho, the lesson gets pushed across regardless and it's super helpful. Regards.

[@J_HNP]

Totally agreed. Conceptually, this video has shared important information, but the visual examples seem much less dramatic than they should. Visually, I would say that the 32:1 (5 stop difference) presented in this video is more like a 8:1 (3 stop difference) in my experience. If the presenter wouldn’t have cupped the light meter with his hand while measuring the fill side, he would have landed on a much more visually accurate representation of contrast ratios. As in, by blocking the “spillage” from your key light with his palm, he’s removing a large portion of the light that is hitting the “fill side” of the face, resulting in an inaccurate contrast ratio measurement.

[@andresirot9286]

What a great and well explained video !!

[@vistek]

Thank you André!

[@tommynikon2283]

Yeah baby....I learned how to in 1978- photo school. Then it was a Gossen Luna-Pro; now it's a Sekonic. WHEN you LEARN how to use it, HOW to interpret the results, and USE those features as needed....your photography will improve. Because if you think just pointing a camera at a gray card is going to give you gray- you're right! But you're also mistaken thinking pointing the same at a White and Black card is going to give you anything but gray. And for flash photography, indispensable.

[@scarlettstoever8093]

This was SO helpful! I was getting confused where exactly the meter was supposed To be pointing.

[@vistek]

I'm glad it pulled something together for you! Thanks for the comment!

[@jamesdrake3651]

Best video out there I have seen on this topic. Thanks.

[@vistek]

Thanks James - I super appreciate the comment! It was done in a bit of a rush, but I'm glad someone got something out of this!

[@thecookiedirector9685]

This is the video I've been looking for! Thank you so much 😉🙏🏽

[@vistek]

Thank you TCD!

[@rageshgovindan]

Short and so valuable content. Thank you

[@vistek]

Thank you Ragesh!

[@TheEli008]

Great tutorial!! Very well explained.

[@vistek]

Thank you Eli! Really appreciate the comment!

[@MGritts22]

Thank you for accounting for the background and hair light ratios! Was digging for these resources

[@hugocalvo8287]

Excellent video man !

[@vistek]

Thanks Hugo!

[@VincentTartar]

Great explanation and enlightenment on this dark concept. Thank you !

[@vistek]

Thanks a ton Vincent! Dark concept indeed, haha. D

[@sakthivel75]

@@vistek yes it's a nightmare at starting stage of career.you made it simple in this video.

[@vistek]

Thanks you Sakthi!

[@AhadJibon]

If I keep the back and hair light same in my sense that means we are making no use of hair light to separate the subject from background. We are just using the contrast ratio between key and background light. I always prefer the hair light to be more of a hard source.

[@vistek]

This all depends on the colour of the hair. A 2.8 on blond hair will read considerably brighter than 2.8 on black. Also the colour and art direction of the back ground and the subject have a massive impact on how the separation reads.

[@vimalneha]

This helped me understand this metering. I will buy one!

[@vistek]

Thanks for the great comment!

[@Skanda1111]

Amazing explanation. Your so confident. Thank you

[@andrehines]

easily the best video on youtube covering this topic. thx much for this. Can we get another on the advanced features of the sekonics, like on choosing fps and setting up underexposure profiles?

[@vistek]

Thank you andrehines! Great idea. There are a lot of features on modern light meters that we could certainly expand upon. I'll add it to the to-do list for 2019. Thanks for the suggestion. -D

[@philpritchard5173]

I enjoyed this very much, thx. I am always curious though (just in general about exposure)...why not use spot metering for the face? Or..why not use the incident meter on the background? In general, I am not clear why incident light is used to measure exposure, since the camera is always seeing only reflected light? I.e wouldn't spot metering everything be more accurate to what the camera is seeing?

[@vistek]

You can absolutely use either meter in either situation. But you’d also need to know how you want the skin tone rendered. As in, do you know exactly how many stops over or under middle grey your chosen skin tone is? With incident, you don’t need to think about that. Just place the globe next to the face and set your aperture to the meter. Primarily I use my incident meter for controlling lights, less about what the camera sees. If I know I’m 1.5 stops over, I can hold out my incident meter and have a tech adjust the light until I’m happy with my meter reading.

[@philpritchard5173]

@@vistek Hiya...thanks very much for the reply...Are you saying then that the Incident meter is calibrated mainly or only for skin tones...i.e. Middle gray, whereas the spot meter is not, necessarily..?

[@vistek]

Incident and Spot are both calibrated to 18% grey (don't worry, I know this stuff can be confusing). How you use each one is a bit different. Incident tells you what your light is doing, whereas spot tells you the dynamic range of your scene. When shooting film, you don't have scopes - so to the eye (unless you shoot a lot of film), you don't know what's going to be over or under exposed. That's where spot meters come in. You can measure everything in your scene to make sure it's in the pocket of exposure. Ultimately, it comes down to practice. None of this makes sense in conversation form. You need the meters and you need to use them for it to really make sense.

[@philpritchard5173]

@@vistek Thanks again for your reply. Much appreciated.

[@23codez]

Fine, I am stupid. This video got complicated REAL QUICK. I stopped it at 2:33. You couldn't pay me to finish watching it. Holy mother of God, this dude was speaking Chinese.

[@indigoinarritu6096]

Thank you for this video. It was very informative.

[@vistek]

Thank you!

[@indigoinarritu6096]

You win a free spritz if you’re ever in my neighborhood in Italy

[@MengL33]

Thanks a bunch. Best video on this out there.

[@bambangsupriadi9223]

Contrast Ratio is not only used to calculate the intensity ratio between Key and Fill Light. But, also to measure the comparison of the various parts in the frame. It seems that what is demonstrated is only a comparison between Key and Fill Light, so it is more accurate to say it is Lighting Ratio.

[@vistek]

Perhaps you didn’t get to the part where I discuss background intensity with the spot meter.

[@bambangsupriadi9223]

@@vistek The lighting ratio as well as the contrast ratio can both be calculated using a lightmeter, either by measuring the incident meter or reflected (using a spotmeter). Actually, what I'm discussing is not a matter of the facilities used, but matters relating to the terms "contrast ratio" and also "lighting ratio" and their meaning.

[@cristianperaltafoto]

Amazing video, finally I found the perfect video to explain everything about ratios and lightmeter with examples. thanks a lot. One question, why you not metering the background with the bulb?, cuz is reflected to the subjet?.

[@vistek]

Thank you Cristian. And yes, because we are interested in the reflected light (what the camera sees) and not the actual level of light falling on to the bricks.

[@cristianperaltafoto]

@@vistek but if you put a flash to the wall, then you use the bulb right?

[@cristianperaltafoto]

aaaa excellent, that I wanna know..!! so if you put flash, is with the bulb.

[@beatsforless8179]

Very informative; great value. how did you calibrate your meter? and you have the profile DTS use in this video??

[@vistek]

Hi BFL. Thanks for the comment. The meter is factory calibrated. You can calibrate meters to your camera system (camera sensors can be +/- a stop sometimes), but it was not necessary for this demonstration. I have to admit that I've never heard of a profile DTS before. Even googling it doesn't turn up anything (relevant). Care to expand upon that comment?

[@beatsforless8179]

Vistek | Your Visual Imaging Experts , Sure, the sekonic data transfer software DTS ; use to calibrate your light meter to DSLR , mirrorless and Cinema cams. If you make a calibration profile for camera (Black-magic) via DTS software it will be huge deal. Thanks for replying

[@johnmeric492]

Excellent Video!

[@vistek]

Thanks John!

[@owen0314]

Thank you so much ! This is very helpful.

[@vistek]

You're welcome! And thank you for the comment & support!

[@TeddyCavachon]

A good starting baseline is understanding how to fit scene range to sensor range with fill and key lights. Put a white and black towel over a stand or have subject hold them. Set camera to f/stop desired for DOF and shutter speed/ISO then with fill source placed directly over the camera (i.e., “neutral” so camera POV will not see any shadows it creates) then raise its power until detail is seen in the black textured towel. Note the white towel will be under exposed at this point. To correctly expose the highlights to the limits of the sensor range raise the power of the key light until the white towel is just below clipping. If measured with an incident meter pointed dome down at each light you will find the key light is about one f/stop over the fill - this will vary with the DR of the sensor. With that baseline “match sensor range” ratio anything placed at the location of the target will be reproduced similar to seen by eye. For example in a wedding shot the detail of both the groom’s black suit and bride’s white dress will be faithfully reproduced. From that baseline starting with more fill (with black towel rendered dark gray) then adding the key to just below clipping will result in “softer” looking light because the shadows are lighter. Conversely starting with a slight loss of detail in the black towel target will produce lighting perceived as being “harder”. The rate of transition between highlight and shadows is a function of the distance of the lights to the subject per the inverse-square law. Positioning the fill center and far away will result in more gradual front-to-back fall off of the shadows. Positioning fill to the side opposite the key risks creating a lighting pattern with very dark, distracting and unflattering shadows in the low areas like smile lines and mouth on faces and the camera seeing shadows from key and fill crossing. Starting with the fill centered ensures it reaches everywhere on a face. When fill is placed

[@HaimGreen]

Great video and info, the model so sweet and pretty ...

[@vistek]

Thanks Haim!

[@GRACK0]

This is gold! Thanks!

[@vistek]

Thank you Gracko! Really appreciate the comment!

[@marczekowski753]

That was a great video. Thanks. I was wondering why you switched to reflective metering for the background?

[@vistek]

Hi Marc. Thanks for the compliment. I switched to reflective for two reasons. 1. Simply as a demonstration and a way to discuss the topic of reflective light. 2. Even if I did incident reading, it still doesn't tell the whole story - where as reflective tells me what the "camera" sees. So how much light does it reflect back etc. We typically skip the reflective metering part nowadays since we can use WFM or false colour meters. However it's still useful for those shooting film (photo or motion), or for gaffers/dps who are setting up a shot but the camera isn't in place yet.

[@marczekowski753]

Thanks for your reply and explanation. I thought about it after I sent my question. The way I think about it is that all the other lights such as key and fill fall on the subject. The light that's illuminating the wall does not. So the best way to take a meeting for the wall is to use the reflective method. Just my thoughts.

[@christianescobar2211]

Super helpful! Thank you so much!!

[@DeStiniEDmeTaL]

Hi, I don't understand the part at 3:16 , where the spotmeter shows F8 but why does Dale says that it is F11 and based everything off on F11 for the keylight when he explains the light ratio?

[@vistek]

Hi Wilson - if you look closer you will see the reading comes in at 8.0 and 9/10ths. Which effectively makes it F11. Also note that the term you intended to use is "light meter" or "incident meter" - because a spot meter is specifically the type of meter that only measures reflected light, not incident light. Hope that helps!

[@DeStiniEDmeTaL]

@@vistek Oh yeah sorry i meant lightmeter earlier! Thanks for the reply! Yeah i just looked up on how to read F stops and understand now! Thank u so much for such a useful video!

[@vistek]

Thanks Wilson!

[@Johannes-222]

Can someone point out why we measure the background with the eyepiece? Or more precise why we measure the illuminance at the model and luminance at the background? I hope those are the right terms for it in english ^^ Thank you for the answer!

[@vistek]

Hi Joey - I think a detailed explanation is outside the scope of this little comment section, but let me try to see if I can sum it up. Most often you want to know what your main lights are "doing." You're looking at them in a way that is *somewhat* unrelated to what you are lighting. That's incident (using the globe). Then you have to consider that some things are shiny and reflect a lot of light, while other things are matte and absorb light. And then a lot of things are in between that. So how light "reflects" off of things very much matters to what the camera sees. For that we need to measure the reflected light. This is where we use the eyepiece / reflective meter. Hope this helps!

[@talapathyratinam9710]

Thank u so much ...🙏

[@deviland05]

Thanks for this video.

[@vistek]

Thank you Andy!

[@zhenyucai]

Best tutorial about lighting ratio and metering! I am a proud Vistek customer. A quick question about metering the background. Can I place the meter on the background with the lumisphere facing the background light? Is it same as using the reflected lens in the video? Seems the incident light metering is emphasized everywhere.

[@vistek]

Thank you Zhenyu! Really appreciate the comment. As for your question; you will have a different reading with your incident meter (globe) than you will with your spot meter. The globe measures light value from the source, whereas a spot meter (or your camera's internal spot meter/false colour) measures the reflective light as seen from the aspect of your camera. For example a shiny metallic object reflects a lot, where a black object reflects very little. Also the position of your incident meter matters considerably and moving it even and inch or two (depending on how close to the light you are) can change your reading.

[@zhenyucai]

@@vistek Thanks for your help. Appreciate it. I guess I was curious about why you switched to the spot meter to measure the background in the video. Was it your recommendation when it comes to measuring the background?

[@vistek]

I was just trying to show all the tools that are available for evaluating exposure and contrast levels. Sometimes the best tool you have is just your eye and to put away the gadgets and just make it look good to your eye. Even though we have all these tools, they should be a quick reference. Don't over think it. :)

[@zhenyucai]

@@vistek Got it! Haha, I admit I do have this tendency to over think about the technical details. Appreciate your help here!

[@RonK]

excellent, thanks! But I am a bit confused: the table at the end says "64:1 = 5 Stops from Key". Wouldn't that rather be "6 Stops" ?

[@vistek]

Hi Ronny, without re-watching to find that moment - I suspect what I meant to communicate is that if you include the stop at the key - then it's 5 from that (but 6 stops is 64:1, yes).

[@m77ast]

Yes indeed. 2.8 is brighter on my camera so it just means it’s darker ie the camera needs more light thanks. But would the camera still be at F4 or would I need to get a new aperture reading based on the combination before I start shooting. Since now I would imagine that the fill will be bleeding in so everything will now be a bit overexposed.

[@vistek]

Your key is everything. Your key factors in the spill from the fill. So you set to your key and park it there. Nothing else to do. If you start changing you lens settings, then your exposure will be off. If you moved it to 2.8, then your key would be overexposed by 1 stop. Meter says key light is F4, you set your lens to F4. Nothing else to do. Everything else is just shaping the light externally to the camera.

[@byronchang4330]

Thank you for the video, now I am finally able to understand contrast ration. I do have one question tho, and it might sound rly stupid. So is f/11 brighter than f/8? Cuzz for lens, I thought the smaller the denominator for stop, the brighter the picture will be. ex) f/1.4 is brighter than f/22?

[@vistek]

Hi Byron. The confusion you're experiencing likely comes from the fact that when the light fixture is brighter the light meter will tell you that you need to use a smaller aperture (higher f-stop number). So, on a lens going down in # = opening up the iris size = letting in more light. Compare that to standing in front of a bright light with your light meter. As you walk closer to the light the meter will keep telling you a larger and larger number; effectively telling you that you must close down (bigger number) your iris on your lens in order to not over expose. This can be a tricky thing to explain in words if you are new to the concept. let me know if this makes sense.

[@byronchang4330]

@@vistek THank you for such a quick response. so when the meter reads f/11 for key and f/8 for fill, it is suggesting that the key is brighter, so that we need to close down the iris? Also, how do decide that f/8.9 is closer to f/11 instead of f/8? Would it perhaps be easier if we measure in footcandle?

[@vistek]

Hi Byron. All great questions. I'll answer the last question first (re footcandles). You can absolutely measure in FC or Lux, but that still won't (simply) tell you what to set your camera lens to. So it's just objective information, what you do with that is sort of up to you and probably makes it more complicated than necessary. Stick with your regular meter readings. Regarding your first comment. Yes, in the case you put forth, I would set my iris to f11 and know that my fill is 1 stop darker (2:1). If you set your iris to f8, then your key (at f11) would be over-exposed by 1 stop. Regarding your remaining question about stop fractions. Some meters can be set to read either decimal places (1/10ths essentially), in 3rds, or quarters. So you'll either see f8.9 or 8 3/4 (ish). Obviously decimals are more precise, but I would hesitate to assume that you'd notice a difference between 8 3/4 (8.75) and 8.9. So whichever you use, either would suffice. In the case of fractions, unless it's a 1/3 or 1/2 - we just round down or up, because the difference would be nearly imperceivable.

[@j-smack4147]

This is great. Is it an issue that her hair is getting crushed to black while her skin is exposed? The hair light is more edge lighting so how does one resolve that issue?

[@vistek]

Thank you for the comment/question. None of that really matters (or likely doesn't) because your recording medium should be robust enough to alter this in post production. If you want more info, just boost it in post. Even when shooting film, we have some latitude here. It's also subjective - maybe we want the hair crushed. Detail doesn't always equal a better image, as it can be distracting to the eye and lead us away from where we want the viewer to look. The last factor is display. On my monitor, it may show plenty of detail whereas on yours it may be crushed.

[@j-smack4147]

@@vistek thank you for your reply! This is a very helpful insight

[@eltalcuate]

That means that if you want to have a 16:1 ratio, you always have to set your keylight around f11 or above? What if you want to shoot with a keylight for example... in f2.1? Can you get the same f stops below? And what it depends? the camera latitude?

[@vistek]

Hi Jonathan. Ratios help you decide on a look or exposure control - and it's up to you to know the subtleties of the medium in which you're recording. Film latitude vs Rec.709 video, or vs Log etc. All very different amounts of latitude. In either case 16:1 is a four stop difference. So your key can be anything, as long as your fill is four stops below key.

[@omarperez4272]

I understood totally, it's great! but have one question... I'm not sure what's the difference between 1:32 or 32:1, the "1" is supossed to be the highlight on the person/object? or it depends? please solve me doubt

[@vistek]

Hi Omar. The 1 refers to the Key Light. Everything is always in reference to your key light.

[@TheIQProductions]

I'm confused about why you retracted the dome and blocked out the key light when metering the fill light? because your key light is spilling into the fill side of her face and vice versa. When you dim down the fill light you are also affecting the the brighter side of her face (so it is no longer an f11 reading on her face as you measured first time round) can you please calrify my confusion? many thanks

[@TheIQProductions]

@@vistek Thanks for your reply! As the keylight reading was f11 with no fill light, when you then turned on the fill light, that light creeped into the key side of her face which means it would no longer be f11 and its not a consistent reference point that stays the same in all the ratios. Also when you took a measurement for the fill light, you retracted the dome and didn't account for the pollution from the key light that creeped into the fill side of her face which surely means the ratios are inaccurate? Because of the angle of your lights and other factors, theres no way of making sure your ratio of 8:1 (for example) is the same as someone else's ratio of 8:1 unless you are consistently taking measurements of both key and fill sides and adjusting both your key light and fill light till you get the measurement you are after in the final frame (accounting for pollution from both the fill and the key lights) which I didn't see you do in this video (maybe it was cut out?) I would be really grateful if you could help me wrap my head around this because at the moment is doesn't make sense to me. Thanks so much!

[@vistek]

Hi IQ. I deleted the previous comment - my mistake as I wrote it in a hurry. It's the opposite of what I said. Dome retracted for key, dome shielded for all fills. You are correct in that all fills effect the key, but then all fills must be separated to know specifically what that exact light source is contributing. So the question (loosely) of "what if you really wrap the key around to the fill side - obviously this would contribute to a higher fill power because of the key bleed." However, we're not interested in that. That's really just about key light placement. It should ideally not be complicated to understand at all. We only want to know two things: What is our key (the main light plus the contribution of all other sources on the key), and what is our fill LIGHT FIXTURE doing? How 8:1 (for example) appears will be different depending on not just light placement but also recording medium (film stock, picture profile, camera's dynamic range, etc). So it's entirely possible that one person's 8:1 could look different then mine - as long as the math holds up, it doesn't matter. If I measure the key with an open dome and I get F11, then walk over to the fill side, and cut out any other light pollution and get a fill reading of F4 - then it doesn't matter how it looks, it's mathematically an 8:1. The only constant would be our eyes. If you light enough, you start to get used to how various ratios look by eye.

[@TheIQProductions]

@@vistek Thanks for your reply again, I really appreciate your help! I understand what you are saying. Can you explain the reason as to why we are only interested in what the fill light (light fixture) is doing and not the key light?(because it does exist and it will show up in the final image and isnt that the only thing that matters?). I think the reason im having a hard time following, is because i dont understand the reasoning behind why the pollution doesnt matter? Ratios would make a lot more sense to me if you just used the incident meter with the dome out and measured your key side and then measured your fill side and then the difference in stops between the two would make your contrast ratio.

[@vistek]

Hi IQ. As long as the fill is going to be the same power or less than the key, then its pollution is hardly an issue. It is unlikely to contribute much in way of exposure. Additionally if the globe was out and we factored in all light falling on the dome for the fill side - we'd have no idea which light is doing what. Add to that the fact that where exactly in space you place that extended dome matters too - a move of an inch can change your reading. I hear what you're saying, but I highly encourage to not think of this as something so intricate and complex. The light meter is just a single tool. You should also be looking with your eyes to make sure it's not just about levels but about how the light falls on the subject too (arguably far more important). If you're shooting film and you don't have a waveform monitor of false colour, then you have to use a combination of incident reading, spot reading, and your own eyeballs. If you're shooting digital, then you also have all these other tools available. I use my light meter the most when I work as a gaffer or lighting technician. The ability to rough in a contrast ratio for a DP while not having to go back and forth to the monitor (which can also be a crowded place already), is a huge time saver. Again, this isn't complicated. I encourage you to get 3 lights, a subject, and then try this for yourself. Talking about it doesn't cement it in one's mind. Go take readings like I do in the video and you will see how straightforward it is and how irrelevant the bleed from key on to the fill lights are. The only time that's relevant is the shape of the light falling on the subject - and that, you should be able to see with your own eyes. Good luck! - D

[@TheIQProductions]

​@@vistek Thanks for such a detailed response! I think the direction the key light is coming from and how much the key is wrapping round into the fill side is important because it changes the look of the entire image. If I tell a gaffer to give me a 4:1 on a subject, the level of how dramatic and contrasty the final image looks is all dependant on how much the key wraps round into the fill side of his face, and isn't the final image the only thing that matters? not what the lighting fixture on set is doing? why is that useful? surely the only thing that matters is the level of contrast and drama in the final image and what the final image is conveying? Am I wrong in thinking the solution to this problem is having the dome out to read both fill and key and then the difference between the two is my contrast ratio? I hope what I'm saying works. Sorry for the back and forth, just really desperate to get my head around this. haha

[@benolson444]

at 5:06 I'm confused. He refers to f 4 as three stops BELOW the key, which is f 11. But isn't going from f 11 to f 4 "stopping up"? I get that it's a 3 stop difference, but f4 is a larger aperture than f11, so shouldn't the fill be letting in more light, not less?

[@vistek]

Hi Ben, when I say stops below key - it means to our eyes, we see a darker image (fill side), and thus we are looking at 3 stop values darker to our eyes. This is a common confusion because on your camera f4 means one thing, where as when we use a light meter to measure scene values, it can mean the opposite.... sort of. All you fundamentally need to understand is that a light meter is simply telling you what to set your aperture to in order for middle grey to look like middle grey. But when we evaluate multiple light values across the scene - like in this scene, I certainly would not want to swing my lens to f4 as it would cause the KEY (@f11) to be wildly over exposed. Our key at f11 is fixed, and all other light meter readings are in reference to that key. So to our eye f4 is going to look 3 stops darker, or colloquially speaking "below key."

[@m77ast]

I still don’t get it in relation to my camera settings. So I set my camera iso shutter and tells me at F8 with this light I have the correct exposure. I turn on the other light now it’s saying what - F4 is correct exposure. So I think we have to find correct exposure for key and that sets the zero point and then work from there?

[@vistek]

Hi m77ast, it's likely simpler than you may believe. It's all about everything being referenced to your key light (your main light illuminating your subject). If you want your subject to look like they look to the human eye - you do a meter reading. Let's say your meter says your key light is F4 (assuming 23.98 fps, 180º shutter), then you just set your lens to F4 and away you go. The meter is telling you what to set as your aperture. Everything else is referenced to that. So if your shadow side is once stop darker (2:1), your meter will tell you that the shadow side is 2.8. Hows that? Does that answer your question?

[@ILaxative]

Amazing video but i have 2 questions: 1. How would you fix the hair detail loss in the shot once you got the ratios where you want them? I notice the ratios from the light meter were correct but her hair and neck area had spots that were pink and blue on the false color image showing they were in the loss detail range. Would like to know if you would leave it as is or what would be done to retain detail. 2. What if I can’t control the fill side as in make it darker but I want a higher contrast ratio? For instance, im going for a high contrast ratio and I’m shooting a scene from the side view of the bed where the actor is laying in bed on their side as well facing the camera but one side of their face is on the pillow so I can’t control that fill side. The shot looks very low contrast almost 1:1 or 2:1. Would I just add light on the opposite to boost the contrast ratio?

[@vistek]

Hi BH7. Thank you for your comment. Here is my best attempt at answering your questions: 1. You have to start making minute and precise modifications to your light. Often we place a single or double net just out of frame over the subject's head and tease it to the right spot to just cut exposure on the highlight. You can also use a polarizer filter which can bring down the specular highlights. Thirdly, it's a matter of personal preference. A little bit of hair highlight isn't necessarily a bad thing. I can however be a problem with blond hair where a slight bit of over exposure can make their hair absolutely nuclear. 2. Pretty simple actually. You can almost always sneak in some black fabric just outside the frame to help with darkening the fill side. I've used my sweater more times than I care to mention. It doesn't take much. The second is to move your key light in closer. By moving it in closer, you have to drop your exposure to deal with the augmented light power. This will drop the overall room ambience. If you can do either of those things, then the only other thing to do is bring in a bigger light (which does the same thing as point two).... or window it in the colour grade (though not ideal).

[@ILaxative]

@@vistek thanks so much for that. I was actually trying question 2 out yesterday and bringing in my forza500 helped boost the light contrast. Big help. As for question 1 i get it on the overexposing issue of the hair but I was referring to something like at 4:05 where the false color is showing her hair is pink and a little bit of her neck is in the blue. Reading the false color its saying that her hair and neck has little to no detail being underexposed..I was asking how would you fix detail loss in her hair on the underexposed situation. In overexposure I know I can block or diffuse it but in a situation like that where her face is properly exposed but her hair is pink like that I wouldn’t know what to do.

[@vistek]

Hi BH7 - it all comes down to contrast. Look at someone with long dark hair - just with your eyes. Notice how there are bright shiny parts and dark "nooks and crannies." Even with your eye there are areas of either blown out highlights or crushed blacks. [as an aside, human eyes have a large dynamic range, but is split into highlight mode or shadow mode, so you can't have an HDR experience with your eyes... which is why actual HDR looks so bizarre). So it comes down to contrast... do you want a high contrast image which means there are elements on either end of the exposure that you are ok to lose detail to - or do you want low contrast, which means everything hovers a few stops around middle grey? The only other thing to suggest is to shoot in a LOG or RAW setting that will give you the most latitude out of the image. It's a bandaid fix, but a fix none-the-less.

[@Ivanovfcpys]

How does this relate to the film latitude or dynamic range of a camera? I mean, it's not the same a 4:1 ratio in a RED than a 4:1 ratio in a Rebel DSLR, am I correct?

[@vistek]

Hi Iván. Thanks for your comment. This should have little effect on what camera system you use. Light is light. It's fixed. So one or two, or even eight stops of light are always an exact and specific amount of light. The camera's dynamic range isn't really the issue here. Perhaps it's more an issue of what gamma curve you select or see on your monitor. Extended dynamic range is present the further you go from middle grey. Most of Hollywood films bases the contrast ratio "look" (how 8:1 is sort of your classic dramatic look), off of either the latitude of film stock, or Rec.709. Of course if you're looking at a log profile or even a hyper gamma, 8:1 will look very different than 8:1 with a steep contrast curve, like in 709. At the end of the day, 8:1 is always 8:1 because it's based on fixed light levels that don't care what camera you're using. How you set up your picture profile will affect how the contrast ratios render. Assume though that 99% of content out in the world is rendered down to Rec.709/2020 for back lit monitors or DCI for projection. Hope that was helpful. - D

[@Ivanovfcpys]

@@vistek Very! Thank you so much!

[@robertobrito3996]

Thank you very much for the video. I have a question, let's say I want to set my aperture to f /2.8. I do the measurement and adjust the lights. How far can I go or how do I measure if in terms of stops my last stop would be f /1? What would be 8:1, what if I wanted to have a 16:1 or 32:1? Maybe the question sounds a little silly, but I eat the doubt, I hope you can answer, thanks!

[@vistek]

Hello Roberto - not a silly question at all, but I do struggle a bit to completely understand. I do think I can answer you in a satisfactory way. 8:1 is a 3 stop difference. it's important to learn your stop scale by memory. If you are exposing your subject for f2.8, and you want an 8:1 ratio - then yes, you are correct - the fill side should read f1 on your meter. Beyond f1, as you go hunting for deeper contrast, you may just get a "low light" reading from your meter. Some will take you down further to .7, but you will likely have to make an exposure compensation with your meter in order to start to see greater than a 3 stop difference with a 2.8 key. I would just lift the ISO on the meter 3 stops (so you're key will read f8). That should buy you some space for deeper contrast. I hope this makes sense!

[@GosfordLawrence]

Whats that meter called. Would love to buy one/ Can you provide a link?

[@vistek]

Hi Gosford, it's the Sekonic Speedmaster L-858. Here is the listing at Vistek: www.vistek.ca/store/414178/sekonic-speedmaster-l858d-light-meter

[@marcotestani7589]

Hi! Just a question, how do we want the presence of the fill light in the reading of the key light? Many thanks! Great video, one of the most useful I have found!

[@vistek]

Thank you Marco! To answer your question, it is because the fill light will always reach over to the key side and contribute to the overall reading of the key. It's minor, but it should always be factored in if you want the most accurate reading.

[@blueraised]

Awesome tutorial!! I am sure I will be referring to it often!!

[@vistek]

Thanks blueraised! Super appreciate it! I may also suggest screen grabbing the last frame with the 1 to 5 stop difference. Keep the jpg on file for a quick lookbook reference.

[@adrianpatterson5776]

I finally understand lighting ratios now!

[@vistek]

Awesome! Great to hear Adrian! It's never easy to communicate technical stuff - glad it got through. Happy shooting! - D

[@pragmaticapproachenglish6875]

sir i want to know that it is understood the ratio difference thing between the key as well the fill light but at the end of the day what would be the f stop final one in a camera setting. r lets say if we decided to shoot on 1.8 to get a bokeh effect but then on the basis of the aperture decided 1.8 already how to do this ratio this in key n fill ?

[@vistek]

if your meter says your key light is 1.8, then you set your lens to 1.8. Pretty simple! If it says 5.6 and you want 1.8 then reduce the power of you light until the meter says 1.8.

[@pragmaticapproachenglish6875]

@@vistek how about foot candle .. ohhh i m very confused . from where to start .

[@robertogiustiresplandordelaluz]

Hola muy bueno pero como seria la relacion 2 a 1 cuando tienes la luz del sol? gracias

[@GregStonham]

Was about to flick past this, then noticed the Dr Strangelove reference...

[@gustavotrovao7044]

I've been reading the manual for Sekonic's L398, which is an analog meter but uses the same principles, and it says to point the dome to the camera for incidental light metering. Even if I do this, it would give me different readings accordingly to the place of the subject I would be scanning (brighter or darker). So, should I take multiple readings and make an average and see what's the exposure values for that average? What about if the subject has many lights and shadows? How many readings would I do? This doesn't seem practical at all... For outside distant subjects (landscapes, middleground buildings, people in a scenery...) the manual says to take a reading from camera position (I don't know if this means just a few meters from the camera and pointing towards it or just paralel to the ground catching light from the environment), to take another reading pointing directly to the sun and to do the average. The only situation in which the manual says to point the dome towards the light source is with lumidisc on (or the dome retracted, in newer models), from the subject perspective, to measure incidence of one light a time, for contrast ratio calculation, as you are doing in this video. In addition, it says to use the lumigrid near the subject, pointing towards it, to read reflective ligh. Is that the way light meters inside cameras work, they just meter reflective light? How should I use this afterall? Where should I place the meter in relation to the camera and the subject, and pointing towards what?

[@vistek]

Hi Gustavo. You're meter manual seems rather confusing or misleading. Likely in just the way it was written. Incident domes should almost always face the key light. Then you can walk around and also meter all your other sources (fill, ambient, back, etc). You could just hold the incident dome at the subject's face and point it to the camera. This will give you an average reading, but not an exact one. For amature photographers, an average metering was often all that was needed. So that might explain your manual's explanation. You should be able to follow my description in the video and get replicatible results.

[@sakthivel75]

@@vistek but I've been told to point the dome towards camera by many famous cinematographers.kindly explain me this and why??

[@vistek]

Hi Sakthi - Pointing the dome at the camera gives you an over-all evaluative measure of the light (light coming from all directions). This can sometimes be used to get "a feel for the room" so-to-speak. It's a general measure, but not a precise one - unless you used your hands to block certain directions of light. So if you were not at all concerned about ratios and just wanted to get an over-all read of the light falling on the scene; you throw up your light meter - point the dome at the camera from the subject's position - and whatever reading you get is a good starting ball park - at least for digital recording.

[@randallburgess6393]

Awesome very useful info thanks so much

[@vistek]

Thanks Randall!

[@vlpixs9photography312]

Good explanation thank you very much

[@vistek]

Thank you vl pixs! Appreciate the support!

[@nathanielperry4166]

Super helpful!!!

[@vistek]

Thanks Nathaniel!

[@ozgemmo3445]

Just a tad confused why you still had the light meter dome set in the incident light position (fully out) rather than in the reflected light position (fully in) when you did your last reflected light measurement? Doesn't this situation actually give incorrect readings? I have just purchased the L-858D (feb, 2019) and am still very much learning how to drive this remarkable light meter so would greatly appreciate your answer. Cheers

[@vistek]

Hello Ian. The incident dome is incident regardless of what position it is in. Retracting the dome only shields multidirectional light, allowing for a more precise single-direction reading. The reflected mode is through the eyepiece and has nothing to do with where the incident dome is. They are two entirely different methods of measuring light. I hope this clarifies!

[@ozgemmo3445]

@@vistek Thank you for your clarification - much appreciated and keep up the good work. Cheers

[@DatrysiadMedia]

Thanks for this just getting into light Meters myself, one thing I have a sekonic light meter that doesn't have the spot meter option, can I just measure the light bouncing off the back wall by standing next to the camera and turn off the key and fill light to get the same type of reading? Will that be close enough for approximation ?

[@vistek]

Thanks for the comment, Byron. Sadly you can't get a reflective reading without a spot meter. You can use zebras, false colour, or your WFM if your camera has those tools. Spot metering has everything to do with the material light is being reflected off of. So a silver sheet would reflect a much greater amount of light than, say, a black rock. But the light falling on both surfaces would remain identical (if you walk into the scene with your incident meter). You can also get some pretty reliable apps for iOS or Android that are effective spot meters (which is what your mobile camera is using anyways to evaluate exposure).

[@DatrysiadMedia]

@@vistek thanks for the response, very much appreciated, I've got a monitor but really enjoying the practical nature of using the light meter. Had a feeling it would be the case but always best to get the help of a professional. Thanks for the tip regarding spot meter and mobile phones will take a look.

[@robertogiustiresplandordelaluz]

Hello very good but how would the 2 to 1 ratio be when you have sunlight? Thank you

[@vistek]

Hi Robert, Light is light. Doesn't matter the source. For example if your sunlight is giving you an f16 rating on the sun side, and lets say an f5.6 rating on the shadow side you have an 8:1 ratio. The exposure of your fill side is based on what is bouncing light back into the shadow side (pavement, trees, neg fill, etc). So you could have a 16 or 32:1 outside, or something much less like a 4:1. Does that make sense?

[@robertogiustiresplandordelaluz]

yes very importan your comments thank you !!!!!greetings from Argentina !!!!!

[@mdfaisalvideo]

Thanks man

[@vistek]

Thank you!

[@JeffintheD]

Thank you! New to photography and filmmaking. Just shot and editing my first music video in fact. Would you recommend a light meter for someone like me, or is an amateur fine with using in-camera meters and software?

[@vistek]

Congrats Detroid Buckeye on your first MV. I believe that light meters are always a useful tool. Every serious DP has one and knows how to use it. That said, if you are always behind a monitor, you can accomplish the same effect with false colour. However, if you are lighting a set and cant stand next to the camera, only a light meter will tell you what you need to know.

[@JeffintheD]

Thanks very much.

[@FilmmakerTery]

Thank you for this!

[@irinaanisimova5827]

I think it is confusing. Why we need to say about ratios when we can just talk of stop difference? Is it easyer?

[@vistek]

Yes. Easier, faster, and creates a mental image in someone's head about a look.

[@liquidmocofilmsllc4915]

I completely agree. Why not just tell the light guy hey, my fill is at f11, give me a fill 3 stops below that please (or shit just tell him give me the fill at f4). Simple. I think the more you get into the upper echelons of any industry, a certain amount of snobbery is inevitably invoked thus bringing in unnecessary bureaucracy. I watched his false colors the whole time and it would have been much easier just to calibrate the lighting using the false color. The other thing is if he changes any of the other parameters i.e. iso or shutter angle, he has to measure all over again and re calibrate the lights. I think the younger generation needs to grasp on to the technology at hand instead of using dinosaur tools. Obviously a genius invented false color for a reason so we should use it. Enough with the snobbery. It reminds me of the old guys in sound recording swearing that analog and tape were the only way and now you have entire bands pumping out records using garage band with a few inexpensive plugins.

[@MrCgs60649]

This applies to still photography also ?

[@vistek]

Absolutely. Light is light.

[@AI-zt9pb]

quick question, how do you measure the background lighting without the spot meter? I have an analog sekonic light meter. do you just do it with the dome?

[@vistek]

You could go up with in incident dome, but it's not going to give you the reflected light value - which is what the camera sees. Remember all surfaces have different degrees of reflectivity - so an incident meter won't account for that. The only way to measure the BG is with a spot meter, false colour, or a waveform monitor. Cheers!

[@AI-zt9pb]

thank you for the prompt reply. so technically it won't accurately give me the measurement needed for the background lighting. what about measuring green screen lighting ratio to the subject? is the same theory applicable?

[@joechido1]

Thanks!!!!!

[@vistek]

Thanks back at you Jose!

[@sajeevsoman3460]

Thanks

[@vistek]

Thanks for the support Sajeev!

[@mynamemysurname7806]

i'm just a little bit confused: You say that the LR 64:1 = 5 stops... (at 9'37") but it should'nt be 6 stops?

[@vistek]

Correct - I may have misspoken. 64:1 is a 6 stop difference.

[@mynamemysurname7806]

thank you! :)

[@robertogiustiresplandordelaluz]

thank you friends

[@januzajadan9060]

Hi Dale! Thanks for such an informative video! I have 2 questions: 1- Do you calibrate your light meter with your camera? 2- So my takeaway is that incident light meter is for the subject while spot meter is for the background. Is there any case where i should go with the opposite direction? (Incident for background and spot for faces?)

[@vistek]

Hi Januzaj. Thanks for the comment! Here are the answers to your questions: 1. Yes. Always a good idea. Every camera (even within the same brand - and depending on picture profile / gamma some times) will interpret ISO/ASA differently. So I have compensation built into my light meter for certain cameras. If I’m shooting film, then I don’t compensate - it’s accurate. 2. Incident and Spot work interchangeably. They are giving you two different types of information. The incident is telling you what the lights are doing and the spot is telling you what the camera is seeing (referenced to middle grey). Spot address the issues of surface light absorption or reflectivity. Whether it’s on a wall, a face, a car, the sky, or a calibrated grey card.

[@januzajadan9060]

@@vistek this is amazing! Thank you so much! Have a great day!

[@imtiazokc6522]

is Paula from India?

[@vistek]

Hi there. I think her family heritage is Portuguese.

[@imtiazokc6522]

@@vistek her eyes are so much indian! Pretty

[@imtiazokc6522]

@@vistek i loved your video full of knowledge!

[@travisshannon8562]

Who is saying light meters are relics?

[@austinatencio5454]

perfect

[@vistek]

Thank you Austin!

[@kuunami]

Paula is beautiful.

[@MrCgs60649]

Thanks as this was very helpful !

[@vistek]

Thank you!

[@kimkrohnberle]

5:1 ratio @6:40 .... #busted Thanks though, informative video.

[@Photographicelements]

It's green in the matrix and blue in their real world. Tank I need an exit...

[@AllThingsKen]

Paula = hot

[@hugox66]

Someone else understood the reference to Kubrick? Lol

[@fx_gtx9495]

K not °K, the Kelvin scale is an absolute temperature scale.

[@hyprz]

wtf all the ratios looked exactly the same

[@vistek]

Hi hyprz, thanks for your comment. I'm not sure how to respond to this - but are you comparing her fill side to the key side? Because they definitely change. Maybe the brightness on your monitor needs to be adjusted. - D

[@djJanKit]

There is a difference, but the location of lights can not see a significant difference on the side of the face. Newbies may not understand the lesson. To be clear, you need to put a key light with a greater angle to the actress

[@GirlWithTheFilmCam]

The key is so soft (is this a Chimera softbox perhaps?) it wraps around the face making the ratios less noticeable in this example, but therefore shows off how useful light meters can be when your eye may not be able to tell a difference. IMHO Fresnels are better used examples of how the lighting ratios look on the subject.

[@cheponchocho2]

Vistek means steak in Spanish... Mmm... steak...

[@tomaszsobczak7817]

4300K it is daylight? Bool shit