The Science of Deep Focus and the Hyperfocal Distance

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Orson Welles is known for deeply choreographing the staging in Citizen Kane - but that blocking would have been lost if it wasn't in focus. In this Lab we explore the concept of Hyperfocal Distance and how you can utilize this concept to shoot deep focus shots to get the widest depth of field your lens is capable of.
If you have any further questions be sure to check out our questions page on Filmmaker IQ:
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[@anaveragefilmmaker1422]

How is this man not a course teacher or something because he's better than almost every other person who I've learnt from in the years I've been studying

[@SungazerDNB]

But he is, we are in his classroom

[@Tstinzy]

This is probably one of the best videos on KZbin. Expertly explained and no extra bs. You are incredible!

[@johnschnorr7768]

I can't understand why this channel doesn't more subscribers. It's great, I'm mainly a stills photographer and I learn things every video. All those film school students out there should be watching this channel.

[@lunacarmin]

Lubezki is amazing, natural light on the wild THE WHOLE MOVIE, a true achievement!! I also loved children of men from his work.

[@neilseiffer]

You can save a lot of money and time using natural or available...Stanley Kubrick was known for that.

[@anaveragefilmmaker1422]

@@neilseiffer Wait how's this relevant?

[@mskonicki2001]

Zero dislikes, better stay that way you jaded film students, this man is a genius.

[@chirag4]

agree, this is no mean feat or achievement, Kudos to Filmmaker IQ Team

[@FilmmakerIQ]

Just wait....

[@HarryRobins]

Someone must have thought, "Hmm, I don't understand this. Therefore I should dislike this".

[@fuckugplus]

now that someone said it............

[@Ryantothec]

Thank you so much for making this video. I've been screaming the past several years that shallow depth of field and blurry backgrounds are an epidemic. It's crazy because now that everyone can do it with their DSLR, it's become synonymous with amateur video. It makes me sick watching too much shallow depth of field, shaky cam and super tight close ups!

[@FilmmakerIQ]

Yeah, it can also lead to an overreliance on editing and essentially zero physical blocking - everything becomes flat and 2 dimensional.

[@boxingpunchalot9521]

Do you cry at night thinking about it? #1stworldproblems

[@UpperState]

@@boxingpunchalot9521 Yes: media1.giphy.com/media/1GT5PZLjMwYBW/giphy.gif?cid=6c09b952wagyqj6q4w06jdehe4q8b3mr74g335xzrc043g00&rid=giphy.gif

[@Roamer_sea_manila]

I want more movie examples on your videos, that will make them perfect

[@eberbacher007]

true, some examples would be really great

[@ntinakoulas]

i am proud to say i finally understood everything about this video. i had to check some english terms and to ask some things to my school teacher BUT NOW I GET IT

[@amstrad79b]

Thank you John! Your videos are enlightening to say the least! I am 17 years in the television and advertising business and I am learning new stuff on each and every video you publish!

[@DIYCameraGuy]

I love using my old manual lenses when teaching DOF and Hyperfocus. It always a good day when I see your videos in my feed.

[@laromande]

You guys are doing a greater job on each video, this new lab series is truly amazing and all the technical aspects you go through are just so accessible and clear. Definitely my favorite channel, thanks a lot

[@cuisined]

Nothing short of Amazing+++. John Hess, every time I encounter one of your lectures I am so pleased to delve into them as they are food for thought. You are a bless to the industry and to those young filmmakers who exist and being inspired by folks like you. THANK YOU.

[@sparkybluefox]

Mr Hess, Once again, you take an arcane subject and make not only interesting, but downright FUN! Thank you so much for treating us to another Awesome Filmaker IQ video. This is one I will surly watch again just to soak it all in. In one word: BRAVO ! SBF

[@uzyoc]

I have new respect for the “Director of Photography “ in movies

[@antonioarrm]

Excellent video as always! You are truly great, I used to teach photography and I really appreciate the effort you put into these awesome videos! Keep up the magnificent work please!!

[@TheFilmLook]

Thank you for sharing this! Will be testing this technique out on the next short film, awesome stuff :D

[@syekbe]

Love your channel, I'm so glad you guys are back!

[@MaxxMcGeeImpactStudios]

Amazing episode! Such a damn high quality you provide in these videos.

[@EduarFilms]

awesom! thanks for this! I always had this issues when I wanted to keep everything in focus!

[@tuentinqarantino4106]

You and your team are doing an amazing job Sir. Thank you.

[@asbelbls]

i love this channel, especially the way everything is explained it makes it so easy to understand

[@SaturnCanuck]

Very nice. Well done.

[@ARickyRodriguez]

This is golden! Awesome!

[@miniatureface]

Thanks soo much for all the invaluable information you have given me

[@zakariaabed3593]

Great one just keep this advanced lessons, hope we can see another important topic soon Keep going

[@arsenymun2028]

I was a bit in a circle of confusion, now I understand thanks to your video)

[@neilseiffer]

Great video. Coming from a film background and a still photographer, as a DP I'm experiment with adapting my 40mm Zeiss Distagon lens to my canon 5D Mark 3 using a fotodiox Hasselblad lens adaptor. It does convert the lens to approx. 64mm with an impressive "deep focus." Keep in mind that shallow depth of field in commercial films sometimes is necessary to prevent background objects from being identified for copyright and trademark issues.

[@gabrielsmith6600]

ask people to like your videos! You guys deserve it!

[@FengXingFengXing]

Remember use same units for all variables in equations (convert mm become m). For CG this is easy.

[@virendhemre5237]

Great teaching ❤

[@htorres1stk]

Whew! Rough stuff, but stuck though it and learned a lot. Thx

[@friend5625]

It's a fantastic job

[@Sameir8055]

Definitely, we should give the bouquet some rest and try for the deep focus. Thanks for the great mathematics... practical example gave me some breath.

[@krisinsaigon]

Thanks!

[@Luckylukeproduction]

THANK YOU!!!!!!!!!!!

[@bharathkrishnan2634]

Marvelous

[@FreshSqueezedLightning]

I’ve always been a fan of deep focus, super shallow DOF has become synonymous with DSLR n00bs who don’t understand dialing in stops to the amount needed, they just slam it wide open for the “trend”. Excellent vid as always!

[@marioleos2987]

Very Comprehensive.

[@Dolencd]

Damn! F40k Netflix! I'm binge-watching this channel from now on. :)

[@douglas.barbosa]

Awesome concept! BTW, where did you do those 3D models intro for every video u have? They're so cool!

[@FilmmakerIQ]

Thank you! They are all built in 3D Studio Max.

[@BassistBob81]

Just found your awesome channel! Great content and presentation! Something I noticed about the shot from Citizen Kane at 1:26 ...Would that technically be Split Diopter? I noticed that the wall directly behind Orson Welles is out of focus, yet everything on the right side of the shot is indeed in Deep Focus. Just curious, I'm no expert but it reminded me of certain shots in the film The Andromeda Strain, which used Split Diopter lenses.

[@FilmmakerIQ]

Looking at that shot from a different source - it may have been a split diopter - though the right side is using hyperfocal distance. Still that shot probably could have been produced today without the diopter - my shot at the end of the video comes pretty close and I was using a 35mm. A 24mm on APS-C would probably do it.

[@TheGuggo]

Another great production by Filmmaker IQ. Thank you so much. Two years later from when this video was released, I don’t find the recommended app (HyperFocal Pro) available, at least in the UK Apple Store. Any suggestion for a valid substitute? Thanks.

[@SanjaySharma-vr8rx]

Great 👍👍👍👍

[@EscapeMCP]

This is what they need to use for 3D films, rather than the shallow DoF that they seem to use currently. It's so annoying focussing on the foreground, only to find once you have got your eyes to focus that the object is in really soft focus on the celluloid. Using the technique described by John would fix this problem in an instant. I guess it would affect the focussing/framing decisions of the 2D version of the film too much, which is why you don't see it done. It's a shame, as 3D in it's current shallow DoF format is just wrong. It's not how our eyes see things naturally so when you see a 3D movie, it just looks all cattywampus.

[@cementarygate]

la jolla? great work btw

[@richardcooper8260]

Great explanation, Appreciate your info! Im searching for the Hyper Focal Pro on the Apple App store but I am not finding it. Is this an android app only?

[@RothmanHarv]

This is just what I wanted. Thanks! There's a time and a place for bokeh and hyperfocal so it's fun to have both. Does the hyperfocal calculation take into account the risk of diffraction? Also, what about the risk of noise with small apertures, 'cause won't the exposure or ISO have to be cranked up?

[@FilmmakerIQ]

+Harvey Rothman no these calculations do not consider diffraction. But diffraction is not related to DoF... Everything gets blurrier, even the subject that's supposed to be in focus. ;) Small apertures do not cause noise, underexposure causes noise. So if you feed the sensor/film enough light you won't have noise issues. That in itself can be a challenge

[@NomeDeArte]

I'm really grateful that you use the metric system like everyone in the world, it's really helpful!

[@mrdrgonzo]

A split field Diopter filter can also be used.

[@ellozy]

Great video, will be using this soon I hope. One question though, the equation you showed. Does that give you the Hyperfocal distance in feet or in meters?

[@FilmmakerIQ]

+Ahmed El Lozy the equation gives you whatever figures you put in. Put in meters, get meters. Put in feet, get feet

[@1panomotion847]

respect

[@photozen8398]

Thank you for the video, on the manual lenses with colored indexes, how to negotiate 5.6 aperture that does not have corresponding marks on the lens's barrel, all the other stops have that but for 5.6 it does not and that is on all manual Nikkor lenses, I have the 20 mm f4 and am puzzled by that particular aperture approach.

[@FilmmakerIQ]

Just guess or use the lens calculator. Those colored lines aren't super accurate.

[@subhadeepdey911]

With Filmmaker IQ you first like then Watch because it shares best knowledge in the KZbin 👍

[@CameraCheckChannel]

Why is it possible to use film scenes? ...Thanks for your videos!!

[@RCAvhstape]

I just noticed the flying saucer in the intro makes a TIE Fighter sound effect.

[@chengong388]

Bokeh is an easy tool to add focus to your shot, so you don’t have to worry about the other things in the frame. Easy so it’s overused.

[@neonerfilms]

Wow! I was there last month shooting! Did you take these pictires yourself?

[@FilmmakerIQ]

Yep - went on kind of a miserable day though.... took the manual 35mm lens out to see if I could pull it off and was very happy with the results.

[@denialvanish]

Filmmaker IQ is simply the best, hands down. Considering the "sensitvity" of the subject (no pun intended), it's a wonder the 4Fs (Fxxxing Full Frame Fanatics, or Bokeh Junkies) haven't chimed in with their holy war against smaller sensors and cinematic composition. Oops...

[@rainerup]

Great and helpful video. Just can't find the recommended free "Hyperfocal Pro" app. Any suggestions?

[@FilmmakerIQ]

You can use any depth of field app you find. They all use the same formulas - you're just picking out which one has the aesthetics you like. They might slightly disagree with each other because the way they handle division with very small numbers - but in practice they don't have any major differences.

[@leandrolefa]

Great video, once again! It left me wondering and I'll ask here before I do my own testing - how do lens adapters affect all this, is at all?

[@FilmmakerIQ]

+Lefa I'm not entirely sure. I've heard that Nikon adapters to Canon can't focus to infinity. That's probably because the Canon flange distance is one of the longest in the industry. But Canon to other models _should_ be fine.

[@leandrolefa]

I kept my Nikkor lenses when I bought a GX8 (50mm became 100mm!!!), which will indeed focus to infinity. I'm trying to mentally figure out the physics involved in the lens being placed further away from the sensor and how that affects focus. But it's friday night (GMT +3). Hard to think so much. I'll try to sneak time for testing amid pile of work. :c)

[@FilmmakerIQ]

+Lefa basically everything off slightly on the scale printed in the lens barrel.

[@FilmmakerIQ]

+Lefa BTW still have my Nikkors from the lens adapter days. They're still very good lenses

[@leandrolefa]

Right! :c) Thanks!

[@MohammadAbdan]

when you love math as well as filmmaking

[@arpitdas4263]

AAAYYYY

[@sergiomartinez5946]

Hey John, I know I need to stop down the aperture to get a deeper DOF but my image gets dark and if I turn up the ISO I get a lot of noise. Sure I can remove it in Da Vinci Resolve but how do I get a cleaner image? I mean I guess the only solution is to introduce more light?

[@FilmmakerIQ]

Yep. Photography is a constant battle between two extremes.

[@OscarUlate]

In minute 7:15 can someone explain me what that means please. Is it better a full frame or a cropped one for the matter. Thanks!

[@FilmmakerIQ]

Oscar Ulate field of view is how much of the scene is in frame. A FF camera has a wider field of view than a cropped sensor the same focal length. It is not necessarily better or worse.

[@JustinHavey]

Do you not run into problems with soft looking footage when you go past f8? How do you get past that? I was always under the impression you should never go past f8-11(ish). Can someone explain this?

[@FilmmakerIQ]

Actually the contrary is true to me, F8 is where I feel most lenses feel the sharpest. You really don't start to see the effects of aperture diffraction until you get to about f20-f32. We cover diffraction briefly in this video: kzbin.info/www/bejne/eXiqhot3gtGcp68m20s

[@quincybattieste]

"Impressive. Most impressive..." - Darth Vader

[@avada0]

This would be interesting, if I understood any of it. But am I right in thinking that with a good deep focus setup broadcasters could show race-cars that are far away on the straight, meanwhile others are up close making the turn then still others that are going away after making the turn meanwhile everything's in focus and the projective distortion matches the human eye (or even exaggerated slightly). I've grown to despise how they always show zoomed pictures of only one or two cars where you can't even tell if one is 1 meter behind the other or a 100.

[@FilmmakerIQ]

Because most auto races are shot from very far away on cameras with relatively small sensors - they almost always at shooting beyond the hyperfocal distance.

[@doylelacrua]

Which depth of field app exactly? I think I missed it in the video.

[@FilmmakerIQ]

We have more links in our course lesson: filmmakeriq.com/lessons/practical-hyperfocal-distance/ They aren't all that different - the only reason you will find slight variations in the numbers they give you is how the calculators handle long decimals - but in practice they all pretty much say the same thing.

[@rapfreak7797]

What about films where they have two actors at different depths and both are sharply in focus and a lot of the transition zone is blurry. Is this just two separate shots digitally pasted together?

[@FilmmakerIQ]

Either composite of something called a split diopter.

[@rapfreak7797]

@@FilmmakerIQ Thanks man, super quick response! I may be alone but I HATE these shots. Then again I hate when they try to mix audio from the performance with voiceover. Both mechanisms just take me out of the presentation as they stand out obnoxiously to me.

[@FilmmakerIQ]

Split diopter is a film nerd's fetish shot. When film nerds first learn of it, they go nuts spotting it in movies like Blow Up and the first Star Trek movie. And those two films probably constitute 95% of split diopter shots out there. Frankly it's not a good look, it's very unnatural. I personally can't stand the shot either... Either do a real deep focus shot or do a really split screen if that's your intention

[@ninoletigre]

I'm really struggling with this concept of the sensor size effecting the size of the circle of confusion of a lens. I don't understand why using an old vintage lens (designed for 35mm) on a cropped sensor today would change the circle of confusion which seems to me to be a property of the lens itself. To my mind, the only reason the circle of confusion of a lens would be any different on a cropped sensor is if it was designed for a smaller sensor. For example, I can understand why a 35mm FX lens would have a different circle of confusion from a 35mm DX lens... DX and FX lens have different fields of view, but I don't understand why the same 35mm FX lens would have a different hyperfocal distance on an FX sensor and a DX sensor as you suggest at 9:15. So my question is... is it that really the sensor size that's having an effect here or is it the lens design? Hope this makes sense. I love this video series by the way.

[@FilmmakerIQ]

+Tony White Circle of Confusion is simply not a property of any lens. It is a property of a sensor/film size and final projection - magnification.

[@bi1iruben]

The circle of confusion is basically the blurring of the edge of an object extending across several pixels. How many pixels will depend on the configuration of object distance to lens and focusing power of the lens. But how this then relates to width across a number of pixels depends on how many pixels there are per millimetre. A crop sensor with the same number of pixels as a full-frame camera will have its pixels more tightly packed on the sensor. Hence a Canon 1D has pixel spacing of about 8 microns, whereas the 70D is around 2microns. So a 4micron blurring on the full size sensor will fall within 1 pixel, but for a cropped camera 4 pixels. Lastly how many pixels is too blurry depends on how the final picture is displayed/printed: a 4x6" print can have blurring across several pixels without the image looking "unfocused", but for a gallery 1x2m exhibit print the public is going to be pixel peeking all the way.

[@JoergWessels]

Sadly the famous actor Charles Bronson is often confused with a totally and utterly unknown person named James Bronson.

[@kay486]

where is that intro screaming sound effect from? I am pretty sure it was used in the original StarCraft too

[@winkleperiwinkle808]

Jolly Joy it's the infamous Wilhelm Scream 😁 it became an inside joke in cinema, it has been used in countless movies

[@kay486]

I had a suspicion that it was an inside joke, thanks :D

[@kay486]

I had a suspicion that it was some inside joke :D But I actually meant the second one.

[@FilmmakerIQ]

Google "Howie Scream" ;)

[@MondayFeelings]

kzbin.info/www/bejne/gJ2sYaeej5aNftU

[@epiphoney]

This is cool. I don't know why the hyperfocal distance calculator isn't in the cameras themselves.

[@FilmmakerIQ]

Too many variables to put it on a camera... Though old 35mm film lenses had something similar.

[@boing615]

Is there any way to capture depth information as an alpha channel in the real world? In 3D modelling you can render out the distance of objects as a greyscale image (white far away, black close up) then apply this in photoshop to set the depth of field manually in post. Is there any way to do this in the real world then shoot with deep focus and blur manually?

[@FilmmakerIQ]

+boing615 that's what lytro is doing using light field tech. But to me it seems like extremely excessive technology for what little advantage you get out of it.

[@boing615]

If it could be captured quickly it would be great in sports photography but I was also thinking about myself on a macro scale, being able to photograph textures and generate accurate depth channels for the surface.

[@FengXingFengXing]

stereo image from 2+ different positions, then calculate depth channel (z channel).

[@alig6852]

Why the crop factor is divided not multiplied?

[@FilmmakerIQ]

It's all math. whether you divide or multiply the crop factor depends on whether the crop factor is used in the numerator or denominator.

[@AQuietNight]

It appears the development of the film for Citizen Kane wasn't pushed in any manner to help obtain deep focus.

[@DingoAteMeBaby]

fucking LOVE deep focus

[@David-mg1yj]

What are the name of the apps that are available, and where can I get them, please?

[@FilmmakerIQ]

+David Larney look in the sauce in our course page filmmakeriq.com/courses/exploring-deep-focus-hyperfocal-distance/

[@David-mg1yj]

Found it. Thank you.

[@David-mg1yj]

Thank you.

[@BlueSprucePOD]

So how do you do it with lenses with out a distance scale?

[@FilmmakerIQ]

+Chris Schroeder are you talking about an auto focus lens? Try to find something that is just a little farther away than the hyperfocal distance and auto focus on that.

[@BlueSprucePOD]

That's kind of what I do, but it's just a guesstimate.

[@bigredjanie]

So in the circle of confusion, you have to get a glimpse beyond this illusion? ;)

[@jackpjk]

Is that app only on Android devices? I can't seem to find it on my iPhone app store.

[@FilmmakerIQ]

Yes that I'm using is Android only but there are iOS apps that do the same thing. They all use the same formulas - the only difference between apps is how they handle very small decimals. In that case you may see some disagreement between them.

[@jackpjk]

Okay, thank you.

[@FilmmakerIQ]

Sorry, Charles Bronson :P kzbin.info/www/bejne/lXmxe2xpfairi6M

[@RCAvhstape]

I don't get the joke? BTW I wouldn't mind if you did a video just on Sergio Leone's westerns, especially that one.

[@FilmmakerIQ]

There was a mistake in the teleprompter that lead John to say James instead of Charles Bronson. He was so focused he did not notice and neither did our team of monkeys until moments after it was posted. - Dennis We have been talking about doing a spaghetti western course for some time. Maybe we will get to it this fall.

[@RCAvhstape]

So wait, you aren't the real John? I am disappoint! But happy you are looking as spaghetti westerns!

[@FilmmakerIQ]

No, I am not the real John. I am the store brand John.

[@RCAvhstape]

Accept no cheap knock-off Johns.

[@IvanSchoeman]

Like we say in South Africa: "this oak is poes clever"!

[@boing615]

So you still have to use a small aperture to get this, right? this won't work with the lens opened up?

[@FilmmakerIQ]

Every aperture setting has a hyperfocal distance it's just that the HFD of a f22 aperture will be a lot closer than the HFD of an f2.0 aperture.

[@boing615]

Right, I see. Is there a fixed point at which high apertures cause diffraction or will it depend on the lens?

[@FilmmakerIQ]

There's always diffraction going on in a lens - it's just that the diffraction at a wide open is very slight. But as you stop down, the diffraction gets more and more noticeable. That's why people talk about a sweet spot of a lens - the point in between really wide open which can be soft and really stopped down where diffraction starts to really become a problem. Generally speaking this diffraction you'll start seeing this around f11-16 but again, it's all very lens dependent.

[@boing615]

Thanks for the feedback, very useful and great channel!

[@minhu9701]

Your are insane!

[@jkennethhigginsiii5696]

It’s Charles Bronson - not James Bronson. LOL! Also, interesting pronunciation of bokeh. Not bouquet - but more boh-keh - emphasis should be on 1st syllable - like Boca as in Boca Raton

[@FilmmakerIQ]

I don't ascribe to any one way of saying bokeh because even the Japanese differ on it depending on which prefecture you're from... kzbin.info/www/bejne/j2Glo5looZ2MqcU

[@jkennethhigginsiii5696]

@@FilmmakerIQ Oh I hope I do not offend! I rarely post comments! I'm a film student at CCSF and our Narrative Filmmaking instructor has pointed us to a number of Filmmaker IQ videos - which are wonderfully detailed and super informative!!! Actually, our instructor gives bokeh a French accent (bouquet), so I found it interesting when I heard (your) pronunciation - which prompted my own investigation. Honestly I was trying to be funny and then I thought the alternative pronunciations interesting. I did not expect a response. Thanks again for Filmmaker IQ's always informative instructions!!! JK Higgins

[@travisteacher]

Charles Bronson... not James

[@richardgraham65]

James Bronson? Was he Charles Bronson's twin brother?

[@blodgettshouseofinsanity]

I wish I could understand what the hell he was talking about. It's very interesting

[@FilmmakerIQ]

+Anthony Passaro if you have trouble with here are three earlier courses on lenses to get up to speed: kzbin.info/www/bejne/Z4qsp6mOrdiFa7s kzbin.info/www/bejne/eXiqhot3gtGcp68 kzbin.info/www/bejne/oqXIaqOXaLeni80

[@ragilmalik]

my head!!!!!! my brain!!!!! help!!!!

[@ruedigerwalter8058]

Nokia 808: The minimum distance when using "hyperfocal" mode is 60 cm.

[@FilmmakerIQ]

The Nokia 808 has an 8mm lens. Put an 8mm lens on a FF camera would have a minimum focus distance of 9cm (hyperfocal distance of 18.2cm)

[@Nobody-tu5wt]

So; Wider the lens,deeper the focus Narrower the aperture,deeper the focus Higher the resolution,shallower the focus(due to circle of confusion) Closer the lens to the subject,shallower the focus Bigger the sensor,deeper the focus 😦???

[@Nobody-tu5wt]

Every other person,KZbin video,photographer,videographer says actually the opposite about sensor size,so it's a really big bite for me to swallow right now

[@FilmmakerIQ]

Yes that's true. Bigger the sensor the deeper the focus for the same lens (keep in mind FOV is different). An intuitive way to think about it is what do you do to check your focus: you zoom in. Zooming in is the same as cropping in. You can't tell on the big picture that means the depth of field is deeper but when you zoom in the depth of field becomes narrower and easier to spot what's in and out of focus. We have a Depth of Field Lens Equivalency video you should check out too kzbin.info/www/bejne/oqXIaqOXaLeni80

[@amirosse1]

i thought it's just H= f²/Nc not H=(f²/Nc) + f

[@FilmmakerIQ]

Most people just disregard the "+f" part because it's so insignificant. Like if your hyperfocal distance is 10 meters, what's another 0.035 meters going to really add? But if you derive it mathematically, you have to include the "+f" portion. en.wikipedia.org/wiki/Hyperfocal_distance#Definition_1

[@BrysonHowe]

"Boka" oh God am I triggered.

[@Leprutz]

Do I really need to know the math? I am so bad in mathetmatics. I Know, the app, but still... I mean do I have to understand the math, the theroy behind it?

[@FilmmakerIQ]

Math is really just the logic: it describes the governing principles and the relationships to each other. Do you have to understand it? No of course not. But then you won't be able to reliably use it and master it ... It will always be a mystery.

[@Leprutz]

@@FilmmakerIQ I don,t really see it. Maybe its my language barrier. So whst is the difference between deep focus and everything in focus? Tje depp focus means that everything is recognizable in its details but it is still a tiny bit out of focus? I don,t see any mystery and mastering it... well... I might be wrong but you make seem things overly complicated for something so simple. Correct if I am wrong. Thank you anyway for your time. It,s always great learning something new.

[@FilmmakerIQ]

Everything can't be in focus. Deep focus means getting as much in focus as possible. I'm not overly complicating things, if that's your view then you aren't really interested in understanding any of this and should just stay ignorant.

[@vaishakrk6362]

Weekly uploads???What's happening?

[@FilmmakerIQ]

Really? I thought they went off the air about 40 years ago. kzbin.info/www/bejne/d6HZan6doMtgsJo

[@vaishakrk6362]

For the first time a youtuber replied to my comment. I am so proud of myself.

[@YogendraSingh]

Bigger the sensor, shallower is the DoF.

[@FilmmakerIQ]

It's actually precisely the opposite ;) kzbin.info/www/bejne/oqXIaqOXaLeni80 It's actually the lenses that make the smaller sensors _appear_ to have deeper focus. The explanation is at 5:50

[@YogendraSingh]

sir, then why does the same lens at same aperture gives bigger bokeh on full frame as compared to APS-C? And Mobile phones should have lowest DoF and biggest bokeh as per your theory.

[@FilmmakerIQ]

The same exact lens (not equivalent lens, the exact same lens) at the same aperture actually gives bigger bokeh on APS-C than full frame - it has to because it's cropping in. When you crop in and blow up to the same final image - of course you're going to get bigger bokeh. See the demonstration here: kzbin.info/www/bejne/oqXIaqOXaLeni80m25s Crop sensors actually have shallower depth of field using the same lens - but they don't have the same field of view. If use an equivalent lens - we have to use a wider focal length on the crop sensor. By using a wider lens, the depth of field gets wider - far overshooting the loss of DoF caused by the smaller sensor. You can see this relationship mathematically demonstrated at 5:50 - watch that portion again. As to your question about cell phones - if you put a 35mm lens in front of a cell phone sensor, it would have WAY more shallow depth of filed than a FF sensor - razor thin DoF. But cell phones don't have 35mm lenses. The iPhone uses a 4.2mm focal length lens. Imagine putting a 4.2mm lens in front of a FF camera - EVERTYHING would be in focus. It''s not the sensor that has shallower depth of field - it's the lens reduces the the depth of field.

[@YogendraSingh]

sharing ur theory on my group facebook.com/groups/Chdphotoclub/

[@FilmmakerIQ]

Yogendra Singh it's not "my theory" - it's the definition of depth of field.

[@Mecal00]

but I love bokeh!

[@FilmmakerIQ]

nothing wrong with bokeh - but imagine how much more delicious it would be if you had it more sparingly :P

[@dukenukem8381]

I feel dumb now

[@syekbe]

I'm so confused about this infinity term in photography. I tried looking videos on KZbin but I haven't found any yet. Can anybody explain in plain english non geeky terminology what the fuck does infinity mean in photography and why should i care please??

[@FilmmakerIQ]

+Sy Eckbe literally means light from an infinitely far away source. All light eminates from like objects like spokes of a wheel (or ball if you think in 3 dimensions), the closer you are too the source the more divergent the spokes are, the father away the more parallel they look. Check out this video for more of science of lens: kzbin.info/www/bejne/Z4qsp6mOrdiFa7s

[@MaxxMcGeeImpactStudios]

So when the light rays from a source can be considered as beeing parallel, it's "infinity".

[@JonathanBoring]

First,"first."

[@FilmmakerIQ]

imgur.com/gallery/WRHRa