[HN Gopher] iPhone Macro: A Big Day for Small Things ___________________________________________________________________ iPhone Macro: A Big Day for Small Things Author : lalmachado Score : 158 points Date : 2021-10-11 10:22 UTC (3 days ago) (HTM) web link (lux.camera) (TXT) w3m dump (lux.camera) | sudosysgen wrote: | My Poco F3 does that too - it can actually focus even closer. | It's quite useful for reading markings. | | That said, I often break out my camera and use it's macro lens | when I need serious resolving power. | throwanem wrote: | I've tried this functionality in Halide on my 12 mini, and it's | not half bad in good light. No doubt the 13s with built-in macro | do better, and it's certainly nowhere near the same realm as the | D850 and 105mm macro lens I use for real [1] work [2], but it's | not a bad capability to have in a device that fits in a pocket. | | [1] https://aaron-m.com/wp-content/uploads/2021/01/DSC1250-1.jpg | | [2] https://aaron-m.com/wp- | content/uploads/2020/08/DSC0772-240dp... | uuddlrlr wrote: | Content warning: bug on bug violence | | Gorgeous shots tho | packetslave wrote: | Here's the thing about iPhone photography (and Android too, I | suppose): if you know what a DSLR is, or the difference between | DSLR and mirrorless bodies, _you are not the target audience_. | | Apple isn't trying compete with a $3500 Sony A7R4 with a $1000 | 90mm macro lens. They're aiming for people who see the example | "macro" photos and say "neat! I want to try that". Or the people | who have already bought a Moment macro lens (or one of the other | clip-on/screw-on iPhone macro lenses) and are tired of carrying | it around. | | _edit: formatting_ | marcellus23 wrote: | Also always worth bringing up in these discussions: the best | camera is the one you have with you. A DSLR is obviously a | better camera, but you usually don't have one on you 24/7. | packetslave wrote: | The best camera you have with you _with the lens you have on | it at the time_. | | If I have to pick which of my heavy glass to carry around | with me on a regular basis, the 90mm macro is going to stay | on the shelf most days unless I'm specifically going out to | shoot macro photos. | | My iPhone Pro 13 is always going to be in my pocket. | matwood wrote: | > if you know what a DSLR is, or the difference between DSLR | and mirrorless bodies, you are not the target audience. | | I disagree. I have both a dslr and mirrorless bodies and love | that my 12pro also takes great pictures. Anyone who enjoys | taking pictures should be excited about the cameras improving | on an always with you device. | megablast wrote: | What are you talking about?? | | Sole us continuously improving their cameras on every iPhone | release. They spend a lot of money on doing it. | | They don't care about competing with anyone. That is not their | mindset. They just get better every year. | | You are making up a rivalry that doesn't exist. | amelius wrote: | It's the other way around. People with iPhones look at | professional photography and will say "I want that too", and | they're disappointed if their iPhone can't do it, so Apple | makes sure it can. | [deleted] | PragmaticPulp wrote: | I think the cellphone versus DSLR/mirrorless debate is largely | an artificial internet debate. | | Every real-world photographer I know is very happy that they | can have both a cellphone and a full-size camera and choose | appropriately for the situation. | lm28469 wrote: | > Apple isn't trying compete with a $3500 Sony A7R4 with a | $1000 90mm macro lens | | tbh something like a Nikon d300 with a 200$ lens does a better | job in good light | mithr wrote: | I think that's largely true -- if you frequently need to take | professional macro shots, you'll already have your own, better | setup anyhow, and won't be switching to a phone camera anytime | soon. However, somewhat surprisingly (for me at least), this | seems to actually be good enough to _also_ satisfy those that | do carry fancy cameras, but don 't need to take macro shots | that often... from https://austinmann.com/trek/iphone-13-pro- | camera-review-tanz...: | | > As a photographer passionate about the natural world, I carry | a macro lens with me no matter what project I'm working on, | just because I never know what tiny detail of interest might | present itself. Now with the macro capability of the iPhone 13 | Pro, I feel like I have my "in-a-pinch" macro shots covered and | I can leave the rarely-used macro lens at home. | tshaddox wrote: | I would have guessed quite the opposite: that people who know | about and use DSLRs would be particularly interested in | advancements in smartphone photography. I would have guessed | that such people probably use their smartphone cameras more | often (and more deliberately) than other people use their | smartphone cameras. Heck, I bet a lot of these people even use | their smartphone cameras more often than they use their DSLRs. | Someone wrote: | I think the group of people who know about and use DSLRs is | too small to be the target audience of any of Apple's | smartphones. | | Other smartphone manufacturers might be willing to do a | product for, at best, a few million users, but Apple thinks | focusing on fewer products is the better choice (for them, | and, possibly, for all users because Apple can spend more | effort on each design) | | I would guess Apple's target audience is everybody who wants | to make better photos, whether they know about DSLRs or not. | | Yes, they have RAW support, but I think they find that a nice | to have, not a must for their product. | fastaguy88 wrote: | It is may be worth mentioning that it is very difficult to get | such amazing pictures without a very stable setup -- both for the | subject and for the camera. Even if you have enough light for a | high shutter speed, it can be difficult to compose a macro shot | if there is any motion at all. And, as was pointed out, | lighting/shadows can be tricky when the "camera" lens is just a | few inches away. | ip26 wrote: | Forget about composing the shot, it's often even a struggle | just to keep the depth of field centered where you want it. | (Apple might be handling that via smarter autofocus, though) | | A little sway left or right can be cropped away, but missed | focus ruins the shot. | throwanem wrote: | Halide does focus peaking, albeit only in manual-focus mode. | | In general, though, you're right - I wouldn't want to try for | the same kinds of shots with a phone that I get with a DSLR. My | macro rig weighs about five pounds, which sounds like a lot and | _is_ in comparison with a phone, but between the damping effect | of all that mass and the ability to get a good grip with both | hands, it makes for a much more stable platform overall. | brudgers wrote: | Yes. "Use a friggin tripod" still applies. So does "bring your | own damn light." | CharlesW wrote: | Also, you can avoid touching the iPhone when you shoot by | using a timer, a Bluetooth shutter remote, or your Apple | Watch (Halide has a watchOS companion app). | fudged71 wrote: | Surprised to see zero mention of ring lights. A small ring light | would be perfect for iPhone macros. | jagger27 wrote: | That's a neat idea for an accessory. I bet you could make a | little stick-on or clip-on light pipe that redirects the built- | in flash to a tiny ring diffuser around the macro lens. | slowhand09 wrote: | Google it - theres about a million... | smoldesu wrote: | I see a Lux article, I almost always skip it. Fair warning, | basically every article I've ever read from this site was a fluff | piece intended to take a hit for Apple, promote their iOS- | exclusive app or both. | renewiltord wrote: | The iPhone lens swap trick that it does can be triggered by | holding your fingers over the lenses. You'll see that as your | finger approaches the lens, it will get bigger until it suddenly | disappears when it covers the lens! Very cool! | wyldfire wrote: | This company makes a software product called "Halide" for your | mobile camera, AFAICT it is an iOS app [1]. | | But interestingly enough there's an image processing programming | language called halide, too [2]. | | [1] https://halide.cam/ | | [2] https://halide-lang.org/ | [deleted] | sandofsky wrote: | This comes up every time a post makes it to Hacker News. I can | only speak for the camera app, but I assume the language also | refers to silver halide, a chemical used in film photography. | | https://en.wikipedia.org/wiki/Silver_halide | novok wrote: | Apple's crop / digital zoom with the 1x camera vs using the | telephoto camera has been pretty annoying with the new iPhone 13 | pro. It fails in many cases it's not supposed to, like zooming in | at 3x in a bright day trying to take a picture of a flying bird | or similar in the sky. | shoto_io wrote: | _Wow. I can see every detail of every scuff and scratch. I need | to take better care of my stuff._ | | "Wow," was exactly what I thought when I saw the third crown | image. Incredible. | opensmtpd wrote: | My problem with smartphone cameras(including iPhone) is that they | completely misrepresent the scene. They try to make the colors of | your photos as punchy as possible even when that's not actually | what you're seeing. Older iphones used to capture accurate colors | (which is why I preferred iphone cameras in the past) but now | they produce the same over-saturated, over-sharpened images as | every other phone these days. | | If I want to make my photos punchy, I can do that in lightroom. | For those who don't use lightroom, you can do that in the built- | in photos app. My old iphone 6s produces much accurate colors | than my iphone 11. On the iphone 11, colors are way off and | images are so over-sharpened that I can see severe haloing around | high-contrast areas. | | And those awful noise-reduction watercolor textures... I wish | they would just leave some noise as-is. Get rid of chroma noise | (which is relatively easy), and leave some luminance noise | around. I mean, luminance noise are actually quite nice as they | are similar to film grain. | | I can get pretty close to what I want with raw(not ProRaw), but | you know, I can't even capture raw with their default camera app | even when they are bloating it with useless(IMHO for a stock | camera app) features like portrait mode, cinematic mode, | photographic styles, filters etc. | | I mean, I get why they are doing it; obviously because people | like over-processed photos for their instagram. But it's my pet | peeve... | packetslave wrote: | While this is obviously a promo for the Halide camera app (which | is awesome, mind you) it's full of useful information on macro | photography, regardless. | | This bit in particular caught my eye: "What makes Halide 2.5's | Macro Mode so special? For one, it brings Macro capabilities to | all iPhones." (not just the iPhone 13 Pro) | ImaCake wrote: | I am always happy to defend an advertisement that has | informative content and is up front about it's true nature as | an ad. An honest ad would be a win-win, consumers understand | things more and the product, if its good, gets increased sales | or awareness. | dkonofalski wrote: | I will admit that I got a little tinge of resentment when I | realized it was an ad/announcement for their app but that | quickly subsided when I realized that I would much rather have | educational/informative ads like this than the alternative. | Even if I don't download their app, I got something useful from | this and that's ok with me. | packetslave wrote: | yeah, content marketing doesn't annoy me nearly as much when | it's this good (and this isn't technically CM since they're | open about the fact that they're announcing their new app | version) | flyinglizard wrote: | Going be amazing for people working on PCBs, to read difficult | package markings and to inspect solder pads instead of using a | microscope. | jkestner wrote: | It's nice to have a do-all device, but a head-mounted dental | loupe is hands-free and can light up your subject. | macintux wrote: | Or just old people like me trying to read serial numbers on | electronics hardware. | noneeeed wrote: | Honestly, as someone who is starting to go long-sighted, this | is tempting me towards getting a 13 pro (or Pixel 6 i it is | similarly good). | | I frequently find myself using my phone camera to zoom in on | ridiculously small text on things, but my phone has always | struggled with it. Good phone macro will be a feature I would | use all the time. | gnicholas wrote: | I've heard of people who are very near-sighted using their | smartphones to help them find their glasses. Just hold the | phone close to your face, so you can see it in focus, and | open the camera app. Voila, you can see the whole room in | focus! | Tagbert wrote: | The iPhones have a special magnifier feature specifically for | this purpose. With one tap it opens the camera, focuses close | and does a little digital enlargement on a live image. It | will be interesting if they incorporate the Macro mode in | that feature soon. | mhb wrote: | I don't want to interfere with a rationalization for a new | phone, but how does your phone struggle? I use my iPhone SE | (Gen 1) for this all the time. | gnopgnip wrote: | You can't really use machine learning based image upscaling for | that type of work | bwanab wrote: | I feel the need to point out that Nikon has always called extreme | closeup lenses micro instead of the oxymoronic macro the rest of | the industry uses: | https://imaging.nikon.com/lineup/lens/f-mount/#special. | cfjgvjh wrote: | That's because the original micro lenses were commissioned to | resolve images of microfilms iirc[1] (See under 1962), and | doesn't really have anything to do with the macro/micro | relationship. | | [1] - | https://www.nikon.com/about/corporate/history/chronology/194... | dkonofalski wrote: | These kinds of comments are what I miss seeing in the | majority of posts on HN. Thanks for this esoteric bit of | knowledge! | lostgame wrote: | This is a fantastic nugget of info, thank you! | rrreese wrote: | There is a well understood difference between macroscopy and | microscopy. Naming macro lenses micro might be helpful to the | layperson but not the subject expert. | pdpi wrote: | The name Macro makes perfect sense. It doesn't refer to the | size of the subjects being shot, but rather to the | magnification factor. Macro lenses are capable of preserving | 1:1 scale between the subject and film/sensor | marban wrote: | While the 13 Pro's lens is undoubtedly a marvel of engineering, I | feel like all those 'mind.blown' reviews must have been written | by youngsters who never used a dedicated macro lens on a (D)SLR. | throwaway81523 wrote: | I've never been able to get good macro shots on a DSLR, despite | decent optics and lighting, and an ok-for-most-purposes tripod. | I eventually decided that to do it really right takes a massive | copy stand, maybe on a concrete slab. Stuff wobbles too much | without it. | arrrg wrote: | It's different and each has its own qualities. | | I noticed it during my vacation in Italy. Yeah, I still run | around with a big mirrorless camera with a huge zoom lens | (Fujifilm's weird X-H1 absolutely no one bought but I still | love very much with the very large and heavy 16-55 mm F2.8 | lens) and I'm sure I will only use its photos for my 2022 week | calendar or whatever else photo projects I will do - but the | photos from my iPhone still provided an instant satisfying | value in the way in which they are instantly and easily | shareable and just immediately can populate my digital live | (even if I have the huge camera with me - which I don't always | have!). | | These are two different ways of using photography and both are | valid. More importantly, both benefit from any new capabilities | you gain. | | I guess what I want from my Fuji is to integrate itself more | tightly and easily with my smartphone, something they really | suck at. And I want my smartphone to be good enough in more | situations. Like macro photography. | | And the weird thing about macro is that even if you do have a | big camera and great lenses (I have the 35mm F1.4, 23mm F1.4, | 16-55mm F2.8 and I sometimes rent the 90mm F2.0) you might not | prioritize macro photography, so if you just get a new thing | that's pretty good at it that just very cool to play around | with. And I don't think your sneering attitude is justified ... | alistairSH wrote: | Certainly not the case for this review. Lux produces several | well-reviewed iOS camera apps and regularly publishes articles | about the iPhone camera hardware and software. | defaultname wrote: | Having that functionality in your pocket, instantly usable, | beats having an SLR in the closet at home with a macro lens | that you can switch to for a passing need. | | And FWIW, the curse of SLR macro lenses is _minuscule_ depth of | field, so much so that many take many photos (presuming a | perfectly stationary subject), bracket the focus, and stack by | sharpness. It 's a hugely involved process. A macro lens with a | tiny focal length instantly has a big advantage, though depth | of field is still going to be a problem given the fixed | aperture. | | It most real world scenarios I think the average person will | have a much better chance of successful results. | sudosysgen wrote: | This is a fixed issue in cameras. Stop down to F16, and use a | ring flash, there you go, fixed. | ValentineC wrote: | Wouldn't this also involve needing to use a tripod? | sudosysgen wrote: | Not necessarily, no. If you want a pin-sharp image at | 48MP yes, but if you want something comparable to the | iPhone jacking up the shutter speed to 1/400 makes it | manageable handheld with good stabilization. | bosie wrote: | i assume fixed at 24mm because at 90mm, stopping it down to | f16 won't do you much good? | sudosysgen wrote: | Yes, somewhere around 24mm. You'd need to step down a bit | more at 90mm. | | However, at 90mm the object would also be farther away, | so you wouldn't need to stop down a lot more than you'd | expect. | defaultname wrote: | Few who have ever taken macro photographs would claim this | is a "fixed issue". Macro photography is a giant pain. | Further the difference between a 4mm focal length and a | 50mm focal length, as a function of DoF, is massively | larger than that 50mm going between f2.8 to f16. You'd have | to go to a hypothetical F/512 to get the same advantage in | that particular realm (though in reality small apertures | suffer from their own problems). | | This is basic math. It's interesting that someone else | claimed it's "physics" as a retort, when yes indeed it IS | physics. It's why you can make a tiny lens fixed focus | camera that seems to have everything in focus, from near to | far, because the DoF becomes enormous. | throwanem wrote: | I usually work around f/22, at 1/250 and of course with | flash. I shot this handheld, about a year ago: | https://aaron-m.com/wp- | content/uploads/2021/01/DSC1250-1.jpg | | It's a fixed issue. | defaultname wrote: | Do you think that photo demonstrates that it's a fixed | issue? You seem to have around 3mm of depth actually in | focus, and even with a very, very shallow subject, parts | are unpleasantly out of focus. | | I don't think that is the demonstration you think it is. | Most macro photographers would not rack that up as a | successful photo. | | And again, focus stacking is what everyone does to | compensate for the DoF weakness. | throwanem wrote: | If you know a way to focus-stack a live and highly active | subject, I'm all ears. But where's your work? To judge by | your response here, you must certainly be much better at | this than I am, and I'd like the opportunity to derive | some small benefit from the extensive experience that | gives you so confidently to take such a superior tone. | defaultname wrote: | "If you know a way to focus-stack a live and highly | active subject, I'm all ears." | | You don't, which is why higher depth of field is the | golden standard. See: The entirety of this discussion. | | "so confidently to take such a superior tone" | | To be clear, you dismissed my post by claiming that it's | a "fixed" issue, then posting proof that doesn't show it | to fixed. I don't believe I'm the one who attempted a | superior tone. | | Depth of field is *THE* issue in macro photography. Small | focal length cameras are at an advantage in that regard. | It's pretty simple. | sudosysgen wrote: | Small focal length cameras only have an advantage when | the sensor size is the same. If you are decreasing the | sensor size and keeping the resolution constant, the | "small focal length" camera has zero advantage. There is | no difference between a 4mm lens at f/2 that is a, say, | 30mm FF equivalent and a 30mm full-frame lens at f/15. | Precisely zero difference. | sudosysgen wrote: | I don't see anymore than 3mm in focus in the images of | the post. | sudosysgen wrote: | I have a macro lens in my hands and a stabilized sensor | camera. I can take a picture of the crown of my watch | with a fair amount of detail. | | You have a 4mm lens at f/2. To get the same depth of | field you'd need a 50mm lens at f/25, not f/512. | | You don't need to use a 50mm lens though. Macro lenses | are typically 24mm or so. So you need to shoot at F12 to | have the same depth of field in reality, certainly not | f/512... | | And my camera actually moves the sensor AND the lens | instead of just the lens. Because of that it can | stabilize in the near field MUCH more efficiently than an | iPhone ever could. | defaultname wrote: | "You have a 4mm lens at f/2. To get the same depth of | field you'd need a 50mm lens at f/25, not f/512." | | Humorously years back I had authored a giant depth of | field essay with online calculators specifically because | so many people just _couldn 't understand_ why their | iPhone couldn't get bokeh. Yes, f/512 would be the | impossible equivalent. This is easily calculated. | | Regardless, the lens Apple uses for macro mode has a | 1.54mm focal length. The 4mm example was just | demonstrating how _fundamentally_ small cameras win on | depth of field, at least if you want maximal depth of | field. Conversely they lose when you want to limit depth | of field, which is why we have computational bokeh. | | "Macro lenses are typically 24mm or so." | | The smallest from most makers is 35mm, but the majority | are 50mm+. | | This conversation has turned weird. As someone who has | had many SLRs, and _many_ lenses, and has taken thousands | of macro photos, I know that in the real world macro | photography is a massive pain. That DoF is by far the | number one obstacle (which is why focus stacking is | simply _necessary_ , often with ten or more varied | focuses). Physics benefits small camera systems for that | specific scenario. | sudosysgen wrote: | That's just not how lenses work, fundamentally. Bokeh is | determined by two things, and two things only - the | diameter of the aperture and the distance to the object. | That's it. | | Also yes, the wide angle of the iPhone 13 is much | smaller. Just stop down even further then. | | Cheap macro lenses in 2021 are typically around 24mm. I'm | talking about the Mitakons and the Laowas of the world. | | Focus stacking is needed when you're trying to take very | high detail pictures with 60, 70, 90mm lenses on high | resolution sensors. You don't need anywhere near as much | to take an image with the same magnification as a 13mm | equiv. 2cm away. | defaultname wrote: | "That's just not how lenses work, fundamentally." | | Go to the wikipedia page on depth of field and see how it | is calculated. | | "Cheap macro lenses in 2021 are typically around 24mm" | | You claimed they were the norm. Now it's that they simply | _exist_. | | "Focus stacking is needed" | | Focus stacking is needed when the depth of field is so | small that the resulting photo would be unpleasant. This | is the case for almost all macro photographs shot on | SLRs. It's interesting that someone else claimed this is | a fixed issue and posted a photo that looks like it was | taken with one of those terrible lens adapter kits. If | that is one's standard for "fixed", then sure, but most | of us have higher standards. | sudosysgen wrote: | 24mm is a normal focal length for entry level macro | lenses nowadays, yes. They don't just exist, they are | very common in the entry level market. If you want to get | those kinds of macro shots that's what you'll get. | | If your goal for macro photography is to take a picture | that is reasonably sharp at 12MP 2cm away with a | magnification of less than 2, then yes, getting | acceptable depth of field is a solved problem. Set your | wide angle macro lens to F/22 and there you go. | | If you have higher standards, then the problem is not | fixed on DSLRs. But the iPhone doesn't do it either. | | If you don't understand why using the CoC criteria for | depth of field is incorrect on two cameras with vastly | different sensor sizes, I can't help you. The only | measure for depth of field that works across cameras with | two different sensor sizes is the ratio of distance and | aperture diameter, which determines the solid angle of | light capture. You're the one that brought up physics, so | actually look at the physics instead of using | photographer's ready-made formulas without actually | understanding them and where they break down. | | As for the image that you replied to, it doesn't look any | worse at all to the images in the post technically. If | you look at the image of the lightning connector, it | doesn't even have 2mm of depth of field at a pretty low | actual resolution. You can say whatever you want as for | the composition and artistic value, that's not what we're | talking about. | defaultname wrote: | "I can't help you" | | No, you can't, because you are painfully ignorant on this | topic. | | Literally, spend 30 minutes with an iPhone and an SLR and | you'd be illuminated. Instead you seriously argue that I | need to look at the "physics" (which is farcical when you | ignore the most important part of a camera, which is the | focusing from the lens to the sensor. Dismissing that | betrays a complete misunderstanding of optics). | | This conversation is clearly futile, but again - spend 30 | minutes and actually test your theories. Or, you know, | read _any_ single article on the tubes. | | Or how about simply ask yourself "why does the iPhone | need to do computational bokeh"? 65mm equivalent lens, | f/2.2...should be the easiest thing in the world. In SLR | world that is bokeh gold. | sudosysgen wrote: | I have a phone with a macro lens. I have a mirrorless | camera. As I told you, what matters for bokeh is the | distance to the object and the diameter of the aperture. | The iPhone needs computational bokeh because the aperture | is 2.4mm wide, whereas one of my lenses has a 40mm | aperture. That's why my camera produces more bokeh - the | aperture has a wider diameter while the distance to the | object is the same. | | That is literally the one and only thing that matters. | The diameter of the lens, and the distance from the | object. Take a piece of paper, draw the lens as a slit, | draw the object as a point, and make a line from the two | edges of the slit to the point, that continues furhter | back. You'll get two triangles. Everything that is | contained in those two triangles will be focused to the | same point on the sensor. That's why the ratio between | the two is what matters. That's why closer objects | produce a more out of focus background than objects | farther appart. That's what I'm trying to explain to you. | | The DoF formula that photographers use _does not_ work | for comparisons across two different film sizes. | defaultname wrote: | You understand that cameras don't use a slit, right? Do | you understand the optics in a modern camera? | | Further my 70mm lens has a _smaller_ aperture than my | 35mm f1.4 lens. Yet it has a much smaller depth of field | for a given distance. Weird! Lens makers must not know | your remarkable "slit lens" trick. | | At this point I'm convinced you are either trolling, or | have dug so far into the depths of wrongness that you're | dedicated to sticking with it. So good luck with that. | I'm out of this conversation. | sudosysgen wrote: | Revolve the entire setup around the axis perpendicular to | the slit and you will have a very accurate representation | of how a camera-lens system works. | | The ratio between distance and focal length only works if | the focal lengths are equivalent across the two cameras. | Otherwise it doesn't work. That's to say, a 70mm f/2.8 | has the same depth of field as a 35mm 1.4 lens if the | second is on a camera with 2x crop factor. | | Try it out, crop the image of your 70mm lens at f/2.8 and | compare it to the image of your 35mm f/1.4 lens and you | will get exactly the same image with the same blur | (assuming the lenses are exactly 70mm and 35mm at the | focus setting, which is not guaranteed due to focus | breathing and manufacturers rounding off their focal | lengths) | foldr wrote: | I think you are right if you hold constant the CoC. In | that case the DoF is proportional to the f number but | inversely proportional to the square of the focal length | (http://graphics.stanford.edu/courses/cs178/applets/dof.h | tml). | | However, for a smaller format, we arguably ought to | reduce the CoC proportionally. And I think that reduction | will end up canceling out one factor of f, bringing us | back to the ratio of the focal length to the f stop (i.e. | the absolute diameter of the aperture). | defaultname wrote: | The focal length input is squared, but the CoC impact is | linear. The iPhone has a small CoC compared to SLRs, but | its input on the calculation is undersized relative to | focal length. | | The iPhone is widely assumed to have a CoC of 0.004mm | (this actually increases on the most recent iPhone, | though it's tough to get precise numbers). A Nikon D5000 | (going with an equivalent resolution -- larger pixels -- | on an ASP-C camera) has a CoC of 0.020. | | So let's calculate hyperfocal distance of the two systems | for the same effective focal length (but obviously very | different real focal lengths)- | | iPhone 12 telephoto lens - 65mm (7.5mm real) equivalent, | f2.2. | | Nikon D5000 equivalent lens - 65mm (43mm real) | equivalent, f2.2. | | For the iPhone, the HF is 6.4m. For the Nikon, it is | 54.3m. For those who don't know, hyperfocus is the point | where everything from 1/2 of that distance to infinity is | in focus if you set the focus to that magical point. It's | a proxy for the other depth of field calculations, and is | the simplest to demonstrate. | | Anyone who owns an iPhone w a "telephoto" and an ASP-C | SLR w/ a 50mm lens needs to try to replicate bokeh at | various distances without the computational bokeh. Focus | on a subject at 1m, 2m, 4m, etc at the same aperture. | Close down the aperture on the SLR even. | foldr wrote: | Holding constant the target resolution, you need a | smaller CoC in proportion to the difference in focal | lengths (assuming the viewing angle is also held | constant). That removes one of the factors of f. | | I think it makes sense to assume the same target | resolution for the iPhone and the DSLR, even though this | isn't true in practice. The DSLR user is obviously free | to downsample their photo to a lower resolution and | thereby (in a rather uninteresting way) gain more depth | of field. We shouldn't be giving the iPhone extra DoF | points just because it happens to have a lower | resolution. | | So we are not talking about any empirically derived value | for the iPhone's CoC. The CoC here is a value derived for | each format from an arbitrarily chosen target resolution. | defaultname wrote: | "I think it makes sense to assume the same target | resolution for the iPhone and the DSLR, even though this | isn't true in practice" | | It yields a practically perfect comparison of focus. This | isn't a trick or handicapping, and the degree of | focus/defocus is identical whether that SLR had 10x the | resolution. There is utterly nothing arbitrary chosen | here, and the amount a tree 10 feet outside the focus is | out of focus will be identical on a 12MP SLR or a 24, 48, | or 96MP version with the same focal length / f / sensor | size. | foldr wrote: | My point was that it doesn't matter what resolution we | choose as long as we do the calculations based on the | _same_ resolution for both the iPhone and the DSLR (and | hence with different values for the CoC in each case, | given the different sensor sizes). Thus your value for | the iPhone's CoC derived from its pixel size is | irrelevant. We can choose any target resolution we like | to make the comparison and get the same result | (comparatively speaking). | | By resolution here I'm talking about what we could | crudely measure in megapixels. Say for example that we | have a target resolution of 5MP. We then calculate the | corresponding CoC for both cameras based on their | respective sensor sizes. You'll find that the CoC for the | iPhone will be smaller in proportion to the difference in | focal lengths between the iPhone and DSLR. That cancels | out one of the factors of f. | | Sudosysgen is saying the same thing, but without going | indirectly via the DoF formula that you've been using. | defaultname wrote: | The CoC for the iPhone is smaller than the ASP-C given | the smaller sensor. By choosing the same resolution of an | ASP-C sensor, we are calculating for a given level of | "good enough for that resolution". It is perfectly | comparable level of focus. I have no idea why you are so | caught up in distractions. | | I calculated the hyperfocal length for an iPhone and an | equivalent zoom SLR, at the same aperture. These yield | effectively identical degrees of focus from 1/2 the HF to | infinity. The iPhone is from 3.2ft to infinity, the SLR | is from 27 feet to infinity. | | Nothing else matters if you can't _tell me why that 's | wrong_. Because it isn't wrong. It's absolutely right. | The same zoom level and cropping. MASSIVELY larger focus | zone. | | If we doubled both dimensions of the sensor, thus | doubling the CoC, it would halve the HF. If we instead | doubled the focal length it QUADRUPLES the HF. The focal | length is a squared factor and outweighs any other | component. For a reason. | foldr wrote: | If you double the focal length you also have to double | the sensor size (to get the same angle of view) and hence | double the size of the CoC - so you end up with f*f/f = | f. | sudosysgen wrote: | You can't use the same aperture. The SLR has to be at a | smaller aperture so the diameter of the lens is the same. | That way both will gather the same amount of light and | have the same amount of bokeh. | | That's your issue - you need to use equivalent apertures. | defaultname wrote: | At this point I'm sure you must be joking. | sudosysgen wrote: | The CoC refers to the circle in the pixel that a point | will be focused to. The pixels on an iPhone are much | smaller than the pixels on a camera. If you use the same | CoC for the iPhone, you are referring to many more pixels | than on a DSLR. | | Therefore, when you use the same CoC, you are asking the | DSLR to be dozens of times closer to perfect focus, in | pixel terms, than the iPhone, which is why you are | calculating outlandish f stop values. | | If instead, you have a target that the object must | resolve to a pixel with the same resolution on both, you | will arrive to an f stop linearly proportional to the | sensor size, instead of proportional to the square of the | sensor size. | defaultname wrote: | I _clearly_ used completely different CoCs, factoring in | the different sensor sizes. | | At this point I feel like you are just posting things | hoping some future visitor will think that your | commitment must demonstrate that you are right. I guess. | sudosysgen wrote: | You clearly did not. If you scaled the CoC _exactly_ with | the crop factor, we would find exactly the same numbers. | [deleted] | angst_ridden wrote: | The most popular macro lenses for dSLRs are 60mm, 90mm, | and 105mm. Of course, there are other focal lengths. I | don't think I've ever seen a 24mm macro lens, unless | we're talking micro 4/3 or some other non-35mm sensor | size. | sudosysgen wrote: | If you want to replicate the effect in the article, you'd | be using a 24mm macro lens, yes. Mitakon makes multiple, | and laowa makes multiple for all mounts. | angst_ridden wrote: | I didn't argue that 24mm macros don't/can't exist, I'm | arguing that they're vanishingly rare in the grand scheme | of 355mm photography. | sudosysgen wrote: | I really don't think they are. The 24mm "probe" lens is | pretty famous and widespread, and it's actually the #2 | item for the query "macro lens" on Google shopping and | it's the first macro lens you'll see on Google images. | Beyond that, there's a whole plethora of ~24mm macro | lenses and they're pretty dominant in the budget side of | macro lenses nowadays. | sbierwagen wrote: | Not on a full frame 35mm sensor it won't. | dylan604 wrote: | But that's how physics work. If iPhone Macro doesn't suffer | the same issues, then it's a software trick | packetslave wrote: | I wouldn't call it a "trick" but I suspect Apple is doing | some focus stacking under the hood. | | The image pipeline in the iPhone gets more and more | advanced with every IOS release. The state of the art for | computational photography is pretty amazing. | dylan604 wrote: | If you're doing something under the hood without | disclosing it but calling it something else, it's a | trick. It doesn't have to be nefarious, but you are | tricking the user into thinking they are doing something | which they are not actually doing. | marcellus23 wrote: | How are they not disclosing it? They talk at length, | every single keynote, about all the software they build | to process iPhone photos. | dylan604 wrote: | Do they really? I only ever hear about how its the best | iPhone camera they have ever made. Yes, they talk about | how their AI is able to adjusts exposure, color tone, | etc. Do they actually talk about how a macro is taken in | such detail as focus stacking etc? I tend to nod off | during these videos, so I might have missed something. | packetslave wrote: | They tend to have sessions at WWDC about the underlying | camera pipeline, for developers who care. Product launch | keynotes are the wrong forum for deep technical talks. | dylan604 wrote: | that's not what the person I responded to implied. they | specifically called out the keynote | marcellus23 wrote: | > Yes, they talk about how their AI is able to adjusts | exposure, color tone, etc. Do they actually talk about | how a macro is taken in such detail as focus stacking | etc? | | Is that moving the goal posts a bit? Your point was that | Apple is somehow pretending they're not using software to | create this effect -- if they say they're using AI/etc. | to do it, it seems to me like they're not misleading | their customers. I don't think the requirement is that | they explain exactly how it works in technical detail. | | I don't think they did any sort of deep dive on their | macro tech, but in the past yes, they have gone into some | detail about how their image processing works behind the | scenes. | dylan604 wrote: | There's a difference in macro being 1:1 ratio (as | understood in photography) vs having an AI do something | to make something small look big in the image. So if | their lenses are not delivering 1:1 but use some sort of | algo, then it's misleading. | packetslave wrote: | I see where you're coming from, but here's the thing: | every single photo taken on a modern phone goes through a | pipeline of 10+ stages of image processing, including | multiple exposure merging. The iPhone isn't even taking a | single photo... it's picking the best frame(s) out of a | running buffer of video. | | (unless you shoot in raw, and I haven't read enough yet | to know what processing, if any, Apple does to ProRes/RAW | photos). | | Call it "tricks" if you want. I call it using technology | to give the non-professional camera user the best photo | possible at the time. If that bothers you, pull out the | DSLR, shoot in RAW, and spend time afterwards in | Photoshop/Lightroom. | | _edit_ this is also why apps like Halide (or ProCamera | or Filmic Pro) exist... if you want to control more of | the options instead of letting Apple choose, the | capability is out there. Most users probably don 't care. | They just want a good photo of their kids to post on | Instagram. | renewiltord wrote: | DSLRs use extensive such tricks to process the image. | Enthusiast groups will show the pathological cases for | the image processing that happens. Ultimately, ceci n'est | pas une pipe applies to the picture. It's a | representation and it is meant to evoke the scene. | dylan604 wrote: | What DSLRs use AI or other software based tricks to | perform macro photography? | defaultname wrote: | Depth of field is a direct function of real-world focal | length. An iPhone has camera systems with a focal length in | the 1.4mm - 5mm range (the equivalent framing is not | relevant to the impact on DoF). Most SLRs have lenses with | focal lengths from 35mm - 100mm. | | https://www.photopills.com/calculators/dof | | (That site has different camera selections purely because | the circle of confusion differs based upon the sensor size | / resolution, so it's the relative values that you should | pay attention to) | | Take a gander at the DoF variations for a 4mm versus a 35mm | FL system. | | This is the reason why iPhones have to implement fake bokeh | -- because the depth of field on tiny cameras is so much | larger, even with a wide open aperture. But the inverse is | that where you want a wide depth of field it is a feature | of the size. It's also why people seem to be much more | successful taking photos on smartphones, because the focus | is much more forgiving. | | A wide DoF is a function of those physics. | zippergz wrote: | I've been seriously into photography since well before usable | digital cameras were a thing. I have used very expensive | cameras, lenses, and lighting rigs with 35mm, medium format, | 4x5 and pro-level digital. I am under no illusions about the | difference between a high end dedicated rig and what my phone | can do. But I still find it amazing and delightful to be able | to get such great results from a device that fits in my pocket, | I have with me all the time, and also does so many other | things. It's all about context. | GoodJokes wrote: | Youngsters or people who don't want to and should not spend big | money to carry around a bulky camera to take a picture 1 | million other people have taken a picture of. One always see | people in these threads projecting their insecurity with having | forked over a $1,000 on a bulky camera that is nearly bested by | a multi-purpose phone. | 153957 wrote: | So this is just a digital zoom (crop) with Super | Resolution(tm)-like (machine learning) upscaling... ___________________________________________________________________ (page generated 2021-10-14 23:00 UTC)