The Properties of Camera Lenses 

As a film student who pays around $3000 per semester for this kind of knowledge, I don't even get a quarter of this that you guys give away for zero bucks. I cannot thank you enough for how much you've enriched me as a filmmaker. Thanks to you, in my first semesters I possess much advanced knowledge thank my other classmates, which gave me a huge headstart in theory and practice.

You guys are seriously the best. Film schools should definetely show your videos in class.

This video is one third of my college intro to photography class.

As a long-time still photographer your recent videos have been the best explanation for this stuff I've seen outside of books.

Very impressive. It's rare to find someone in this modern culture who actually does their homework and has studied their subject to the extent that they can explain it without hiding behind techno-speak. I find your videos very instructive in a field about which I understand very little.

Coming from a 34 yo with ZERO exp with film or cinematography, these videos have been an absolute God send with bringing me up to speed with how to play around with this unexpected interest in film. Thank you sir, you are a scholar and a gentleman.

One of the best videos which clearly explains focal length of a camera.

im gonna leave this video tabbed in my browser, i think i should watch it a few more times over the week just to make sure the good info in it sticks in my head. thank you very much for making this!

I've been an amateur photographer since my early teens, and coursed BS in math and physics. This is the most clear, fun, concise, and visually appealing explanation of the basic physics and geometry of photography I've ever seen.

This is one of the few channels where I will watch a video longer than 5 minutes. Thanks for a clear explanation.

Man!!!! No jokes, I could have spent a whole month in school for this same info? thank you so much!!! Awesome explanation and Visual aid!

Every time I watch a Filmmaker IQ video I gotta take a break and digest. It feels like I just took a weeks worth of film classes in 20 minutes. Incredibly well put together and informative videos.

I really like this channel's film making tutorials and in so many points, I could really say that it's the best on RU-vid. This channel doesn't think about making shorter videos to get more views, it makes longer videos to cover the whole concept and lesson, and that's why I really like this channel. Because it explains stuff more specialized and detailed, so I could learn so many more things rather than so many videos stating the obvious that we (Beginner to mid level filmmakers) already know. Please keep on doing this guys.

I love that that home made camera! It is wonderful to see the light coming through the lens like that with absolutely no tech babble around it. Just light and the image. Thanks for putting that together.

It's incredibly helpful how you show simple optical examples in action, it makes everything so tangible.

This explains it better than any photography videos on youtube. Illustrasions are very good.

Just noticed the Wilhelm Scream at 0:07 when the camera tips over. Great easter egg from your sound editor :)

Your Videos are truly the best tutorials among free and paid websites! Thank You

Honestly the best. I've learned more from you than I did in my entire college career. The hardest part about it is choosing which video to watch next! and learning when to stop for the day!

Thx for the great informative video. I like how you present it and you dont cut out the small mistakes you sometimes do while speaking. Most youtubers cut their videos after every sentence what makes your eyes very nervous.

These lectures are just awesome. Just the thing I need to see from the professionals to help me with my C100c and follow focus lenses " Fantastic"

Well done. Everything you need to know and clearly presented. Can't wait to see your next video.

Great insights as always! Looking forward to the video on DOF

Man, those are the absolute best explanations I have seen on the subject in my whole life. You have amazing pedagogy and a genuine talent for technical explanations. Keep up this work!

I love the way you explain how the different sizes in sensors change how "zoomed in" the picture gets, I think all of your hands on tests in this video were great. I have some friends who don't understand these things when I try to explain it to them (I guess they can't visualize it), so now I'll show them this video instead. Thank you :) Oh, and I am So curious as to what you raelly said at 20:00 :D

I have learnt so much from these videos I feel like I'm committing some sort of theft

Suggestion for next video: a look at the post production workflow, specifically digital intermediate and traditional photochemical. Basically how we get from a negative to a theatrical print.

These videos are an invaluable resource. Thank you to the whole team for your hard work making these.

thanks for mentioning focal breathing! I've noticed this in film, now I know it's a thing!

I love how you talk about larger and smaller field of view. Not like the idiots who keep talking about 50mm without mentioning sensor size. As if the 50 is a magical focal length regardless of what camera you're using.

One thing I like about your videos is you just dub over the audio when you make a mistake. This is so much better than putting a big ole' SORRY I MEANT XXXX banner over the movie. GJ and great information.

Great video I'm a longtime videographer and already understood 95% of what you were talking about, thanks a lot for clearing up that other 5%.

This video was very well put together! Even though most of this stuff I already knew as a working photographer (except for the split diopter, that was new!) it was still very interesting to see it all laid out in a simple concise and easy to understand matter. I will definitely be forwarding these videos to people getting into photography/filmmaking! Thanks!

I learned more in the first 7 minutes of this video than I learned in my 2-year "photography" course.

You're a star man. What an effort to make this video. Thanks, we appreciate your work!

The presenter is Exceptionally smart - yet very artistic (see his film direction) and above all - very eloquent- wow!!!!!

Overall an excellent comprehensive video good but while I realize your focus is video, here are a couple of caveats/corrections for stills photography: 1. Focus breathing can be an issue for stills photography. It makes the lowers the magnification/reproduction size of closer objects. If you're trying to get as many pixels on a bird a couple of meters away that is an issue. If you're shooting people it means you'll want to get closer as well. 2. Varifocal lenses are also a problem for stills photography for fast action sports (e.g. motor sports or an airshow). You don't get this wrong but you don't go into it either. Whene you want to zoom while you're shooting a sequence, even if the lens is very fast focusing you're still going to miss some shots with a varifocal lens that you'll get with a parfocal lens. On Nikon compare the Older 70-300VR (parfocal) to the newer AF-P DX VR (faster focusing but varifocal). You're going to want the older lens. Keep up the excellent videos.

As usual, a well researched, well spoken video that will help a lot of filmmakers understand lenses, so thanks again John. p.s. You show a photo of an Arri 9.5-18 lens, which caught my attention. I don't know if you have ever had the chance to play with one, but it is fantastic (although a bit pricey).

These are all the best informative videos on cinema and photography you can find. I'd say ten out of ten except I have to deduct points for consistently referring to silicon as "silicone".

This is a real school photo class! Congrats John!

This was pretty much exactly what I needed. I am a film buff, but also work in physics with a specialty in optics (interferometry, though geometric or ray optics is something I am pretty well versed in). So I had all the science basis, but I did not know the lingo used in photography/cinematography. With this video introducing that in plain terms, I can match up the jargon with what I know from the optics side. Thanks very much for such a lucid video! A couple questions: 1. When the word "sensor" is used here, does it refer to one picture element of the chip, or the the entire chip? In another video, when comparing chip sizes, there was a "number of sensors" listing in the figure that seemed to match up with the number of pixels. This also seemed to be the meaning when talking about the "circle of confusion" in the hyperfocal distance video. But here, when talking about normal lenses as such, the sensor seems to refer to the entire chip. Is there one meaning, or can it vary? 2. When talking about normal lenses and saying they need to be "about the same size as the sensor," does that refer to the diameter of the lens being about the same size? This is what it looks like, but I just want to be sure. Many thanks again!

This is literally the best educational video I have ever seen

As usual, get explanation and supporting graphics. I always learn something that previously was not explained with so much clarity!

A split diopter was also used in Das Boot. Years ago I experimented with macrophoto using extension tubes. It turned out that some extension tubes from my grandfathers large camera (he had used that for making stereo photographies) fitted my modern camera (a Praktica), still using 42 mm thread.

I wish I would have watched a video like this many years ago. All the possible doubts one can have about photography nicely explained in 20 minutes. You are the best dude. Eres la caña! (spanish idiom) Thanks a million.

This channel is very important to all people who want to become cinema I thank you very much for this information and I wish you continued .. I am Omar from Syria I wish you the best

I've been binging all of your videos since yesterday and I love all of them! Great work man, keep it up!

This is an excellent and informative video regarding camera lenses, optics, image-forming, etc. (with a couple of minor "nits" concerning a bit of confusion in the subtitles with "further/farther" and "lens/sensor", and with some "discussion" possible about the meaning of the term "prime"...;-). Left out for macro work, though, was the very useful alternative to extension tubes: achromatic (two-element) close-up lenses. These are often simpler to use, and can be excellent at mid to smallish stops - and they tend to increase lens speed rather than reducing it, as extension tubes do. Where this video was relatively weaker, though, is in the area related to vision - and it included some common, but incorrect, assumptions. A "normal" lens for a given format is an arbitrary value (often defined as a focal length approximation of the format image diagonal dimension), and it has little to do with "how we see". We see with both an extremely wide angle of view (of more than 180-degrees horizontal, exceeding the width of all but the very widest [220-degree] fisheye lenses), and our "attention point" within that extremely wide field of view can be narrower than the longest practical camera telephoto lens. Additionally, "contrary to popular opinion", we see in "fisheye-lens" perspective, which is uncorrected by the brain, unfamiliar as this may appear when seen in a photograph - but this is easy to both prove and to demonstrate...;-) Thanks for making this video - it is generally excellent in coverage, information, and presentation (and it could be a great instructional video with a few "fixes"...). --David Ruether

Great video, John! You covered SO MUCH in such little time. Great channel, please keep it up!

My theory about the "normal lens" comes from the practice of viewing thru the viewfinder and seeing the same proportion as you see with the other eye, both eyes obviously open. Then you have the feeling of a normal viewing, even you can walk and feel comfortable, this is both eyes open, one of them sticked to the camera eyepiece. This assure you won't have a picture with distorted perspective, I mean, the size of the objects in the frame will be the same as the one you can see with your own eyes. So then, in 35mm motion picture film the normal lens would be 50mm, and in FF 35mm film still photography would be around 80mm, due the larger format. The same way, in 16mm motion picture film the normal lens would be 25mm. I know this through experience, but mostly is the way I like to approach the concept of a normal lens, a lens with no distortion regarding the given format. Great channel, John!!!

Hey John, thanx again for all the great knowledge. You videos are a tremendous amount of work and are very slick and easy to follow. Put that feather in your cap bro, you're making a big difference out here in Hollywood. Look forward to meeting you down the road. Thank you & God bless

I love your very informative videos. Please keep them coming! I read Anton Wilson’s thoughts on what makes a normal lens and the 2:1 ratio for normal when shooting for cinema projection. This ratio seems to be very outmoded, however (dating back to the 1920s). Roger Deakins shot Barton fink at 27mm (exactly normal for 1:1.85). Even an “observational” film like Fargo where the viewer is more distant, Deakins only shot at 40mm (1.5x normal). Wally Pfister mainly shot at 28mm for the 1:2.35 movie Inception. I don’t see many contemporary examples of 2:1 in use. The actual selection of focal length/field of view really comes down to creative style more than how it is shown/projected. Prospective filmmakers should think about what suits their story best first (all of these ratios are arbitrary), then consider if a more telescopic look is desired for cinema projection (rather than TV/web). Even when made for the cinema, 2:1 may be much too long and not a good rule of thumb.

Seriously the best youtube lessons.

Thanks for another fantastic video. I'm of the "buy once cry once" philosophy. This information is indispensable when it comes to not wasting money on additional lenses that may be unnecessary for a beginning photographer.

A little late to this channel, but this is serious gold, even for a (primarily) stills photographer. Great summary John.

I always wondered why traditional cinematographers considered 50mm lenses "normal" even though their frames are 1/2 the size of still photographers'. Now I know! Thank you for yet another great video.

I didn't have this at school. Continue the great work. Solid video.

John Hess, Please check the diagram in 1:07. The lens is focused at infinity. This means that the lines that were parallel before entering the lens should converge in a point that is in the image plane.

Wow! I clicked on this not expecting to learn anything new, just to run in the background, but I was wrong! I always thought the "normal" focal length was 50-58mm, same as the human eye; and I knew that too narrow of an aperture would loose sharpness, but nobody really explained why, even though the wave theory of light is as old as photography itself.

very informative, My focus is on camera usage for aerial photography and map making. This information is helpful in determining the best camera and lens for the job.

These videos are so awesome lol. My film class at USC is so much less clear than this. One suggestion is to up the focus and saturation on your face, it seems a little fuzzy and unsatisfying to me.

WOW!!! I have to watch this twice, but very informative!!!

Hey guys, can you do a dedicated video on anamorphic lenses? You know, the history, the technology, the looks... Also maybe talk about why somebody decided to come up with an arguably much harder product to manufacture (in a field as precise and complicated as optics nonetheless) and why people are still crazy about them, despite the fact that we don't really need the sensor "real-estate" anymore? Thank you! You guys have great videos and I've learned a lot about film-making thanks to you. Can't wait for the next one! :)

When I took the "film-making" course at the New York Film Academy they showed one of your videos!

@Filmmaker IQ You're smarter, more knowledgeable and more educated on cinema then any of my academic university film teachers...

I learn more about Lenses and Camera Technique through out your videos than i do in my filmschool. Thats sad and awesome at the same time :D Anyways, awesome video!

Nice video! Explains several key parts of photography in a way that is not hard to understand for beginners. I'm definitely gonna share this video amongst my students.

What a fantastic presentation. Props to Mr. Hess. Great education for me

Thanks for this. It's great, and informative beyond what I would have ever looked for.

great video as always! i feel like i'm in school again; hopefully there won't be a quiz. you are the 'kahn academy' of filmmaking. macro tip: you can also get a reverse filter thread adapter and mount a second lens in reverse for extreme macro shots. if you ever saw the underwhelming sequel to 'repo man,' 'repo chick,' most of the exterior scenes were shot using a tilt-shift lens; hats off to trying something different in film.. 'lens baby' is also a cheap way to create similar, but with non-accurate reproducible results. tilt-shift was originally done on large format cameras, by simply moving the bellows, macro as well. you can also use vintage large & medium format lenses on medium format sensor cameras or cameras with larger sensors, like red cameras (dragon, weapon), which changes the equation a bit..

Subbed. I know a decent amount of video and photography and I learned something new along with a nice refresher. Thanks for sharing.

very thorough explanation- thanks

Awesome series. I would have mentioned that zooms are always invariably slower than their prime counterparts.

Superbbbbbbb tutorial sir. Thanks for your contribution in helping to learn photography for beginners like us

Me hearing John Hess: "Here's how image stabilization works. Science, Science, Science, Tech, Tech, Tech. In other words they use magic." I guess it really is true that any sufficiently advanced technology is indistinguishable from magic.

I highly respect you good sir and hope you continue with these lectures.

Every video is a pleasure. Even when we know the matter, its refreshing to see that knowledge so well delivered. Very good job man.

Normal lens talk at 4:55. Was looking for this. Maybe you should index your videos, but that's a lot of work.

Thank you for teaching so much in such small space of time!

The best video I've seen on learning photography. Looking forward to watching the rest of your videos!

Great video, will you please go over the different types of lens coating please! I always wondered why some lenses from the same company brand, with same focal length and T-stops are priced differently, thanks!

looked up the lens you show at 7:14 arri 9.5-18 and the footage from it looks like its cgi, its that good

awesome video! you guys are great! I just love how you 'perform' the class! Thanks a lot!

The Best Chanel I ever see, A lot of info we learn from your Chanel, Thumb Up keep going Dear.

Absolutely love your videos - thanks a lot!

Best vídeo ever made about lenses.

Absolutely incredible job. Thank you so much for teaching us wanna be directors so much.

Just wow how good your videos are

Thank you for making the videos you make, you've helped me to understand film so much! Keep being awesome man :)

Awesome video! Thanks you :D

I do like your video and.. know the stuff already and watch it anyway.... because it is entertaining in a way. I think, for beginners knowing nothing about lenses your video is nice but could still be more detailed. Maybe this would be better doing one video on zoom and prime lenses, and one special for macro. I think i missed the part where you say that primes are mostly faster. From people with cellphones or bridge cameras with macro funktion i often heard: but i can focus down to 1 cm so what, how´s a macro lens any better? They dont even know that it could be better. The line of thought that focussing at 10cm with a 100mm lens is closer than 1cm with a wideangle should be made clear. The concept of 1:1 magnification. Great video anyway.

I love how just about everything also applies to photography, and I enjoy learning about the distinctions. Blurred boundaries... Maybe next time delve a bit into virtual lenses used in CG...

Good Content. This guy is genius and world is behind Peter Mckinnon

Even the presentation being very enjoyable, there is a technical error: a telephoto lens is not just a lens with a long focal lenght, but one with a focal lenght longer that it's physical longitude from the vortex of it's first system to the focal point. Otherwise, amazing content.

Thanks for this precious videos you make. Just great!

wow.. this is one well polished video.. awesome. caught my attention till the end. thanks a lot. crystal clear explanations. :)

Very comprehensive. Thanks!

Wow. You are awesome at explaining EVERYTHING! Kudos, sir!

I am surprised you didn't mention teleconverters as they are a cheap way to widen or tighten the focal length of a prime lens or zoom.

Another excellent video. Thank you very much for such good information