The Science of Exposure and Metering

This Filmmaker IQ course is proudly sponsored by Northeast Community College, whose Media Arts program offers degree concentrations in Audio Recording, Broadcasting, and Digital Cinema. Please check out their program by following the link: northeast.edu/media-arts/
Help this channel by becoming a patron on Patreon! / filmmakeriq
Let's go deep beyond the exposure triangle and look at the pathway which light travels from the scene to the sensor. In this course we will examine the elements of scene illuminance and luminance, various lens modifications which affect exposure, the exposure itself in terms of aperture and shutter speed, the sensor sensitivity, and lastly how cameras and light meters put all this information back together to obtain the proper exposure.
Full Filmmaker IQ Course with Quiz and Sauce:
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**ERRATA -
There are 10.76 lux per footcandle, not the other way around. I got them flipped because I was thinking there are about 10 square feet in a square meter.
I spelled Optical wrong at 12:00 though if my petition with Webster's is granted, it may just be the proper way to spell it in the coming years.

[@TheSmeagol630]

Anyone else just keep coming back to this video once in a while? This is my fourth time.

[@kentjensen4504]

Third, at least.

[@ankush2275]

Third. Extremely helpful for a reference point

[@TheGuggo]

3rd also for me. Plenty of information

[@richiirichiiz]

I usually get Back here to refresh my knowledge. This is info is the key 🔑 to a camera operator. Thanks for this video.

[@izzyavila6735]

Me

[@lukepensabene6086]

John's not only the best technical film school on KZbin, but he's also super cool in real life

[@FilmmakerIQ]

Thank you! Your check's in the mail

[@lukepensabene6086]

@@FilmmakerIQ ha, didn't think you'd respond so quickly. Good to hear you're active, John!

[@rationalraven8956]

When I see a new Filmmaker IQ video I drop everything else I'm doing and watch, no regrets!

[@johannes914]

Same here !...

[@md.jahirulislam1237]

Rational Raven hmm

[@9and7]

Get the thinking cap on and the notebook and time to learn from the best of the best...

[@kentjensen4504]

Same here

[@horshors3825]

When i hear hi, i'm John Hess, i'm opening my notebook and ready for lesson, thank you so much this is my fav class

[@tlessclock]

The most informative KZbin video I've seen so far about lighting science.

[@denizkendirci]

sometimes people tends to forget that photography literally means graphy of photons. even some people gets angry when you call a photograph picture, they say photographs are not pictures (: fortunately they are so wrong, a photograph is a "type of picture" which uses photons as paint, lens as brush and camera (its sensor) as canvas.

[@darrenwilkinson1742]

long, extremely detailed, mathematical equations. I loved it! exactly what I needed. thank you! don't change, you're a asset to youtube.

[@xakhuh5104]

You sir are the best filmmaking resource on KZbin. You deserve some kind of award. This is a serious education you’re providing so many of us. Thank you.

[@aspirestudios8167]

This is overwhelming but awesome explanation, all the way through!

[@martindoersch]

Aspire Studios so true!

[@TheMichgo]

Being a cameraman of 10years, I totally just learned something new. Can’t wait for more nerdy videos like this. Dynamic range and more formulas please!

[@Lauraraksin77]

@0:15 - Proudly Sponsored by Northeast Community College @0:25 - Intro @0:39 - What is Exposure? @3:24 - The Light in the Scene a. @4:01 - Intensity b. @5:16 - Illuminance c. @6:29 - Lux d. @7:27 - Inverse Square Law e. @8:26 - Luminance f. @9:31 - Recap @10:55 - Lens Modification @13:53 - The Exposure a. @15:47 - Exposure Value System (EVS) @19:03 - The Sensitivity @22:33 - Putting it all together and Spot Metering @26:30 - The Zone System @28:58 - Incidence Metering @31:21 - Closing

[@KarinaRivero]

THANK YOU

[@j.oakley9588]

This is valuable, 100% free information guys. People pay good money for this stuff. And here it is...a mountain of knowledge, literally at our fingertips. What a time to be alive!

[@rafahgd]

I am one of those who watched a lot of videos on exposure (and cinema and video related stuff) and yours is more complete, deeper, precise and comprehensive than the average as always. Thank you for you work. It's gold!

[@aaronbrungardt1527]

i love the wilhelm scream in the intro

[@quitedarkstudio5388]

I feel like I've learned almost everything about exposure thanks yours video. The most scientific channel on KZbin which is about Filmmaking

[@halfsquatchshortbeard3435]

I don’t get why these videos get so little views in relation to subscribers....they are very well done and articulate, makes the majority of the info easily digestible. Hey, John Hess. Why haven’t you pitched a history of film show to any tv studios? This would be perfect for the history channel or something similar....keep up the great work, you’ve gained a loyal subscriber.

[@purplev2791]

Since online videos became more popular and KZbin gives the creator more freedom than TV studios, it would be unnecessary for Filmmaker IQ. I guess these videos only get less views than other filmmaking videos because of the length and the detailed explanation are a smaller niche in the filmmaking niche .

[@909sickle]

It's because he says "make something great" at the end of each video. The KZbin algorithm thinks it's a Trump video and throttles the traffic.

[@AAa-tn5rz]

mad respect to someone who ridicules themselves in their video.

[@FilmmakerIQ]

Pre-emptive strike!

[@devendrapatel197]

I just watched all your episodes and now I am searching whole internet to find quality content about filmmaking just like yours :D

[@BrianIrwin]

As a guy who is finally making some photos that I can live with, I am trying to dip my toe in video. 180 degree shutter seemed like just another random piece of terminology to remember (as random as f/stop), thank you for explaining why the term is used. With how video is exposed it makes total sense. The rest of the video is great too, but this feels like it has taken a load off my mind :)

[@hart-of-gold]

You're a great teacher.

[@FilmmakerIQ]

Thank you for your support!!

[@hart-of-gold]

Thank You, and those who help you. You teach things I know from a different background, (I have an engineering background) and the way you explain concepts is excellent. It has improved my understanding greatly. (your audio videos especially)

[@dipaldesai6956]

He is Modern Einstein

[@stephenbaldassarre2289]

Very well done as always. I learned a long time ago that the most important tool for a photographer, next to the camera itself, is a good light meter. You can ensure the scene is ideal before the camera even arrives.

[@v3gasbaloo]

When science and math are being broken down in pieces, I really like this world!!! Thank you so much!!!

[@maxboissiere4806]

Another high quality video as usual!

[@Dug6666666]

In the category of KZbin exposure video, the winner is Filmaker IQ.

[@dbakhtiar]

i'm so glad i found this video. i've watched a dozen others that repeat the same basic info over and over and leave out key details as though they are some secrets of photography purposely kept hidden. this was incredibly helpful. thank you!!!

[@SpeakerBuilder]

Yes, I know a great deal about exposure already, but I wanted to watch because you are such a great teacher with such an enormous wealth of information, that no matter how much I know, I always learn more from you, thanks for sharing your gift for teaching.

[@thesurfacelevelgamer]

John, your videos are pretty unappealing at first sight (in the context of youtube) but there's really so much in them, not only knowledge but also hilarious stuff, like the opening line about "exposure". When i first found it abt 3 years ago, your channel was more of a thing i watched to learn and supplement my studies, but it is now one of the only essay-type things i watch and enjoy paying full attention to, when i want more than a white noise podcast,

[@davidepaula]

John, you are such a pro when it comes to creating amazing instructional content. I love all of your content!

[@satchmo1991]

Excellent video as always, guys! Looking forward to the next live show!

[@billpancake]

Woooooooo! Another superfluously informative course, John. You da man! 👍🏼

[@tomelifeisjustonebig]

You’re the best man. It’s great to find explanations that are both in depth technical AND practical in terms of usage.

[@justinalbertgrimaldo]

This is the best video I have seen about this on KZbin. All the other ones that I have personally come across are always giving you half of the explanation. This has the whole enchilada. Thank you so much for this. It messed with my brain a bit but after not stressing myself out so much, it clicked. You rock.

[@techsavvydaddy5616]

WOW, I never understood all the science behind Exposure until I watched your video. You have an amazing way of breaking it down and using excellent graphics images to be able to understand the material. You Rock! Thank you for putting this information out there.

[@photosdubfriends4169]

I'm currently studying as a cinematographer, and this video was very insightful. Thank you.

[@theodorecoleanderson7850]

Amazing information man. Please keep uploading videos, you deserve a much bigger audience than what you have!

[@mirageleung1575]

Thank you for taking the time for putting this together

[@miguelherrera9269]

This is one of the best resources I've come across! Thank you very much for your hard work!

[@satyanaraiandubey4168]

Beautifully explained.For some non science students it may be long and complicated. Thanks for such a detailed video👌💐

[@TheDavidN]

As a Producer who is learning to become more a Director of Photography - lighting has always been one of those skills I just haven't nailed down, especially when talking to more experienced tech-centric DP's. This definitely helps make those connections to make the art-to-science translation.

[@sunsetchasers581]

These kind of deep dives are exactly what I’m looking for. Got driven here by the new dual iso video you posted. Can’t wait to catch back up to that vid. Thanks!!

[@yuan-jia]

I wish that course on lighting would've come out someday, it would have been so interesting with your approach.

[@FilmmakerIQ]

What would you like to have covered?

[@yuan-jia]

@@FilmmakerIQ here are a few ideas: - The history of Lighting in the movies: from the greenhouse-like studios of Meliès to to the usage of tungsten, fluorescent lights, HMIs and LEDs nowadays. There’s already a ton of room on this topic alone I think just showcasing the requirements of the cameras of the times, the pros and the cons of each generation of lighting technologies. - The history of lighting styles throughout the ages of film, with probably just as much to say as previously with each era showcasing great use and ingenuity (each decade I think has a signature lighting style but the film noir era namely is probably an iconic style of lighting but even soap operas have great lighting for their purpose and became quite iconic too). I think I could go on if you wanted but it’s already listing an immense work to accomplish lol. Anyways I just thought of that this morning as I told my filmmakers student about the invaluable ressources they can find on your channel before showing parts of this video to give them the best explanation there is around (imo) on lighting units. :)

[@gooseknack]

Highly informative and very in depth. Thanks for the work and effort!

[@mrwashur1991]

You're literally a plethora of knowledge. Thanks for sharing with us!

[@herrreinsch]

this video was so beautiful to watch, enjoyed every second of it.

[@joshuagivans1737]

You guys make really great and unique videos that aren't like any other KZbinrs. Keep up the good work!

[@FilmmakerIQ]

Thank you!

[@reoproedros]

those productions are amazing , thank you !

[@martindoersch]

Greatly done! So informative! 🙏🏻

[@damiankide7889]

thank you so much. this is the most complete explanation of exposure science that you can find in the internet. like for real! and you a great teacher!

[@danielpare9129]

I always learn something new with you. Thanks

[@michaelliuzzi]

Truly grateful for content like this.

[@juancarlospena7089]

Wow! Love this explanation. Well done!

[@RCAvhstape]

This is the kind of Filmmaker IQ video that got me to subscribe in the first place. Great stuff.

[@EricLefebvrePhotography]

*1- Why are we watching this if we already know it?* Cause you are awesome and deserve views. :) *2- The Exposure Triangle* The exposure triangle explanation isn't perfect but it's a good starting point for explaining to someone who doesn't understand exposure at all. Why are my pictures blurry? Why are my pictures all grainy? Why is my picture so dark? All of those can be answered with the basic explanation of the exposure triangle.

[@FilmmakerIQ]

The problem with the exposure triangle is the ISO portion is become increasingly complicated by ISO-less sensors. It also suggests an equivalence between the "real exposure" (shutter speed and aperture) and ISO when there isn't one (this is a source of A LOT of debate in Photog circles) The triangle also misses two key components: Scene illumination and Lens Modification. After a reading everything I've seen, I think the triangle is really kind of a bad way to look at it. It doesn't really make any sense if you think about it deeply and there's no way to represent it graphically that's accurate. The pathway of light however - is a real model of how light behaves in a camera.

[@thaisfrutuoso6265]

Thank you for the masterclass!

[@GiovanniApreaCapri]

I only have one word for this video which is the first ever I watched out of the channel as seen on FStoppers and that word is G R E A T ! ! ! Thank you so much, you present it all in a very simple way which adds to the already great content. GRAZIE

[@joecal2360]

Amazing lesson, thank you so much!

[@shenr0n_]

Very helpful especially with newer digital artists and filmmakers working with virtual and CG based production. Thank you!

[@qnetx]

A superb tutorial.

[@ranakhandkar]

Nicely explained. Thanks!

[@trevormarston]

These videos are so great. I mean I could say a bunch of really hyperbolic things, but they're just really wonderfully interesting and high quality learning material.

[@EugenioTrainer]

Es tan agradable el ver estos videos, puedo dejar todo de lado sólo para escuchar y ver esta clase magistral, gracias por compartir

[@unfa00]

Great content! Thank you for bringing us the knowledge :)

[@smilepleasephotostudio5501]

Excellent way of teaching, great knowledge....I have become fan of you. Thank you for the knowledge.

[@morchedlafferty8614]

Finally understood what ISO actually is. Thank you for your efforts in explaining these concepts!

[@Stone1108]

When I took my Lighting module exams (Engineering, some times ago now) I remember the level of nerves that I experience on my ‘nervous-degree scale’ for this module as being pretty damn high. I just didn’t get it and shamefully only just scraped in on this module, I was just relieved at the time but still didn’t get it. Now, had the whole thing, module, been taught in the manner you have here my ‘nervous degree scale’ reading would likely have been much lower and i’d have walked into that exam with the ‘got this ..’ swagger and probably have put the pen down before time was called ‘hey who knows’. As a photographer this stuff is much more relevant to me and understanding it that bit more important. So i’d like to say thanks, because you’ve just pulled the lever and got three bells in a line and i’m winning!! Well, kind of. I’m learning studio lighting and you’ve helped me to dramatically clear some fog. Double thanks.

[@wallaceshackleton1889]

Very informative and very technical but I learned and understood a lot.

[@mattdavidphotography]

Fantastic video, so educational.

[@Deminimis2]

By far my favorite video.

[@andreathode3782]

This is outstanding! Subbed!❤️👍

[@guystudios]

Very good, sir! Bravo!

[@uzyoc]

Absolutely well made video!!!

[@roderikpatijn1]

Great as usual! Thanks

[@sokolum]

Awesome topic!!

[@tomm.2783]

Beautiful video. Makes me glad I'm a nerd. Looking forward to more of these!

[@l353a1]

Brilliant stuff!

[@dietcock809]

John you are the boss excelent video on the topic

[@rahmatrad4599]

Thanks a lot, your informations are excellent as always.

[@mexicodirk]

This is a fantastic video. 👍👍👍👍

[@speedy3496]

Thanks this was a great explanation of the topic

[@vladbobe26]

They’re back. We missed you!

[@TheGeekyAmreeki]

Thanks a lot man. Very helpful. Don't have to eyeball it so much anymore.

[@funnymono]

Thanks a lot. Really high quality content.

[@azlanarainkhan4549]

Great knowledge and good teaching style Friend.I like your teaching style.this is Azlan Arain khan cinematographer and Director.From Bollywood.Cinemai in India.

[@JefffRushton]

That was a fast 30 mins! Awesome presentation!

[@neopotrebitel]

thank you very much for this video!

[@AAa-tn5rz]

please do a video on dynamic range. thanks

[@FilmmakerIQ]

It's between that and lighting ratios for the next big "tech" one.

[@sanjeetswain7112]

Great class...

[@abdoumca5780]

Job well done!!😍😍

[@NimTV]

I’m still a little lost with a lot of the technical stuff and math, but I do feel as though I have a better understanding of how all of this works in general

[@manudeteruel]

Awesome, thanks!

[@janoti6073]

I love this channel I just know that I have to get Pen and Paper because I will learn a shit ton of stuff no mater how much I think I already know about the topic

[@alistairbuchan]

Its 2023, and this was sooooo damn useful! And I'm an unreal 3D artist. So not just for point and shoot photographers

[@FilmmakerIQ]

The coolest thing about CGI is how it actually tries to mimic real world exposure. People don't realize how advanced and physics-based CGI is

[@tranquocdungk8]

tuyệt vời. một bài giảng rất bổ ích cho những ai quan tâm môn học về kỹ thuật ánh sáng, phơi sáng, đo sáng....

[@thomasbc4515]

Wow Wow Wow - thx for that explanation & work! Greetings from Vienna/Austria - and always everytime a good very good Englisch exercise ;-)

[@djmarzek]

MASTER!

[@Chandasouk]

Knowledge!

[@biscuitsalive]

That’s so odd. I was just reading about IRE and DR and I got a notification for your video. :D

[@FilmmakerIQ]

Not going to get into IRE and Dynamic Range just yet in this video - gotta learn to walk before we run ;)

[@biscuitsalive]

Filmmaker IQ yep so I see. (Watching now) By way I was doing some simple DR testing today on the new a7 mk3.(comparing it to GH5) I would love your criticism on my methods. (Very practical and unscientific, but hopefully finding information that is accurate enough to be useful.)

[@FilmmakerIQ]

I'm deciding between Dynamic Range or Lighting ratios for the next science heavy - I'd be curious to to see your process.

[@biscuitsalive]

Filmmaker IQ it’s all blue tack and duck tape. (An expression I just made up) but it gets me results. And hopefully fair I hope.

[@charlemarcharlemar2401]

It's called tracking you.

[@Tevildo]

Another great video! I didn't know they'd changed the definition of the candela from black-body to monochromatic, thanks for informing us.

[@FilmmakerIQ]

The definition comes from the 16th General Conference on Weights and Measures (CGPM) in 1979.

[@Tevildo]

John, thanks. Shows how long it is since I last did any physics!

[@FilmmakerIQ]

I just didn't want you guys to think I made that up because frankly I am really not capable of making that up. I think I know what monochromatic and black body means but there's no way I could tell you why they matter to Candela without having to look it up first ;)

[@HampshireHog63]

Excellent. That is all.

[@svkarthik19]

Love you John Hess!