[HN Gopher] Shooting photos with an IMAX projector lens
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Shooting photos with an IMAX projector lens
Author : dmitrygr
Score : 162 points
Date : 2021-01-07 01:50 UTC (21 hours ago)
(HTM) web link (theslantedlens.com)
(TXT) w3m dump (theslantedlens.com)
| max_ wrote:
| This seems to yeild some of the "portrait mode" effects. Seen in
| smart phones.
| skylanh wrote:
| Depth of field effects caused by long focal length lenses
| (preferred in portraiture for this reason), called "bokeh". In
| this case the light is coming into front lens elements, and it
| doesn't appear to be corrected for distortion, and then not
| uniformly focused onto the surface of the camera's sensor.
| Potentially this was for a Imax dome.
|
| So, no, this doesn't have anything to do with smart phones.
|
| In ye' olde times, induced background blur would have been a
| gaussian blur in software. I'm not sure what special magic they
| do today. https://arxiv.org/abs/2006.05698 suggests things have
| moved on.
| steerablesafe wrote:
| > In ye' olde times, induced background blur would have been
| a gaussian blur in software
|
| In any case, gaussian blur is definitely the wrong kernel to
| do it. There could be definite improvements before jumping to
| deep learning.
| ygra wrote:
| It's surprisingly common among people who try to fake the
| blurred background. It does look very wrong, though.
| Dirlewanger wrote:
| Didn't Photoshop release a feature in the past couple years
| that does exactly this? Simulated depth of field? And I
| remember watching the demo video and it looked damn good.
| Plus there's that Lytro camera that also allows you to move
| the point of focus around in the picture in post-
| processing.
| ygra wrote:
| Photoshop has had a lens blur filter for ages (I think at
| least back to v6), the trouble usually is to get a useful
| depth map so it can work properly.
| CarVac wrote:
| What a waste on such a small format camera. The IMAX film format
| is larger than even 6x7.
|
| At least use a GFX-100 (which itself isn't even 645).
| jedimastert wrote:
| They aren't using a film lens, they're using a projector lens.
| I don't think the comparison applies?
| codetrotter wrote:
| It's obviously a project made for fun. And you are asking the
| guy to shell out $10,000 for a new camera body?
|
| Edit: of course, renting is an option. But personally even with
| insurance I would not be comfortable with the risk of renting
| such expensive equipment for a project that was purely for my
| own entertainment/curiosity.
| 75rchkiyt wrote:
| Large format film cameras are under $1000
|
| In the case of large format, 4 x 5 inch films can record
| approximately 298.7 million pixels, and 1,200 million pixels
| in the case of 8 x 10 inch film.
| codetrotter wrote:
| The $10k I was talking about is for the GFX-100 that parent
| commenter suggested.
| MayeulC wrote:
| I quite like that format, it looks like a youtube video, but
| unrolled.
|
| I much prefer this than watching a whole video. Less bandwidth,
| less ads, I can skip to the part I want, the content' doesn't
| keep going on while I want to re-read something or examine a
| picture, while it is light on processing power.
|
| In short, I can scroll at my own pace.
| aj7 wrote:
| I disagree. His utter inability in video, and the necessary
| still-photographer kludge that results, are glaring and
| obnoxious. And, in this awful, disjointed slide show, he
| manages to make the same mistake YouTube makers make, time
| wasted on trivial, semi-irrelevant "making," here, the
| woodworking part.
| MayeulC wrote:
| Which I've happily scrolled over while I reached parts that
| were more relevant (to me). It isn't that easy to do in a
| video, here I saw at a glance that the section was going to
| be uninteresting, and if there had been interesting tidbits,
| I wouldn't have had to sit waiting for him to finish drilling
| in between.
|
| Well, at least, I got a simple answer to the question the
| title prompted me: "how does it look". I got baited, but
| didn't have to sit trough it.
|
| (the answer is "not bad, a lot of depth of field, that lens
| is bigger than I imagined, and the resulting quality doesn't
| seem to be worth it).
|
| OK, to be fair, I had missed the "lens" part, and was
| _really_ curious.
| tomcam wrote:
| Step 1. Get an IMAX projector lens...
| m463 wrote:
| step 0. theater goes out of business in era of pandemic
|
| (just a guess)
| jordache wrote:
| there is nothing compelling in this experiment, for anyone who
| has prosumer-level understanding of photography
|
| the lens was designed for a film format with much larger surface
| dimension. The lens' image circle is likewise large - much larger
| than the sensor in the camera this guy used.
|
| So the sensor will just accept a cropped section of the image
| circle projected by this lense.
|
| big deal!?
| djaychela wrote:
| Years ago I got a bit into photography, and I got a cheap M42
| lens adapter after I picked up a Pentacon 135 2.8 [1] - for only
| PS8! It's a great lens, and while I'm not a tech expert, it just
| has a really different look to any of the standard Canon-fit
| lenses I have. It looks a bit like the images in the imax, and
| it's not just that it has shallow DoF because of the aperture (I
| have a sigma 35 that goes down to 1.4). If I wanted a 'vintage'
| look to a photo, I'd use it, and it's great having a large
| aperture lens for very little money that you can see in action as
| it's manual.
|
| [1] - https://vintage-camera-lenses.com/pentacon-135-2-8/ - I
| have the version 2 (less desirable!) one.
| brian-armstrong wrote:
| This lens looks interesting but I think I'll wait until Ken
| Rockwell reviews it before I decide if I want to buy.
| robotmay wrote:
| Ken Rockwell might be the most interesting reviewer I've come
| across in years. What he favours is well known (e.g. metal over
| plastic) but his opinions always feel honest and he's pretty
| pragmatic on what he recommends. Unlike most reviewers (across
| all review subjects) he provides a lot of technical data to the
| point where it feels like it's "ok" to form a different opinion
| from him, and that you don't have to write off his whole
| review. He doesn't tend to get stuck on one fault with a lens
| like many people do.
|
| And his website is easy to read and navigate, which is rare for
| review sites.
| mafuyu wrote:
| Ken's site is great. I don't like his photographs and I often
| disagree with his opinions on gear, but he's very consistent
| and knowledgable. I always check to see if he has a review
| before I buy a new lens or body, especially if it's film.
| jsjsbdkj wrote:
| > It almost has a tilt shift kind of quality like it's you're
| focusing on one point.
|
| It shouldn't be surprising to anyone that knows anything about
| cameras that if you don't have the lens lined up properly you'll
| get a tilt-shift effect. This is basically a rig that does
| controlled "lens whacking", where you don't mount the lens but
| you hold it freely to let light bleed through the mount and mess
| up the focal plane (https://philipbloom.net/blog/the-art-of-lens-
| whacking-real-l...)
|
| I bet if the lens was mounted properly it would look... like a
| normal wide angle lens.
| maurits wrote:
| There is a vibrant community of people experimenting with old
| vintage lenses. Mirrorless full frame camera's are relatively
| easy to make/get adapters for. See Mathieu Stern for inspiration.
| [1]
|
| [1]: https://www.youtube.com/channel/UCYX22a35sKhA0T6ee7uZfvg
| xwdv wrote:
| I don't get it, none of these pictures look particularly mind
| blowing for all that hassle.
| m463 wrote:
| I have a wide angle lens, and if I recall correctly, getting
| the background to blur is harder for the short focal length.
|
| This one is very wide and still blurs the background.
|
| (who knows, it might not be anything out of the ordinary)
| skylanh wrote:
| Depth of field increases as the focal length decreases. It's
| exceptional enough that there are very involved manual
| procedures for taking 10-20-30 pictures with a telephoto lens
| wide open, and stitching them together to give a wider angle
| appearing picture.
|
| Completely spit balling, but I suspect that front lens
| element is worth about as much as a house.
| klyrs wrote:
| It's a fun if janky build, and he's using the "wrong lens for
| that" distortion as an analog framing effect. Not mind-blowing,
| just some curiosity and follow-through.
| behringer wrote:
| I think it's more to do that his shots are not very good. Some
| photographers have more exciting pictures than others.
|
| This lens would be much better suited to nature and panaramic
| shots. Portrait shots not so much.
| hug wrote:
| On the contrary, portrait is about the only thing you can do
| effectively with this lens.
|
| Since it doesn't have a flat plane of focus, you can never
| get any more than a small portion of the picture in focus.
|
| You could maybe do a shot with only a single tree in focus,
| or something, but not a regular landscape.
| dheera wrote:
| Agreed. Also I thought IMAX shot 70mm film which means by using
| it on a 35mm camera he's only using a small fraction of the
| image circle.
|
| A wide angle lens actually designed for 35mm would perform
| better if so.
|
| What he did is sadly a good tactic to get publicity/followers
| though, which in the photography world directly translates to
| more customers and revenue.
| Hnrobert42 wrote:
| I agree that it was disappointing, but I give him an A for
| effort. Even though the idea didn't really work out, I thought
| the video had some interesting information, like the part about
| building a custom mount, having to change a setting to enable
| photos without a lens, and the lighting.
| elliottkember wrote:
| The comments on this post are more negative than I expected.
|
| I really enjoyed this guy's enthusiasm and his "guerrilla"
| setup. It's easy to criticize his method, but he went out and
| shot some skaters with a big weird lens!
| nacc wrote:
| I don't get it. Where is the spec? What's the aperture size,
| focal length of this beast? What about abberations? How does it
| work in extreme conditions that a normal lens can't take a good
| image?
|
| So many questions, but the author decided to use it to take
| portraits in day light ...
| EarthIsHome wrote:
| This reminds me of the article that takes an old spy plane lens
| (Kodak Aero Ektar 7'' f/2.5) and mounts it on a large format film
| camera [0].
|
| [0]: https://emulsive.org/articles/building-a-naked-aero-ektar-
| sp...
|
| [1]: https://www.flickr.com/groups/aeroektar/pool/
| gerikson wrote:
| This is the first article about the Aero-Ektar that doesn't
| freak out about its radioactive thorium-glass rear element.
| [deleted]
| supernova87a wrote:
| Hmm, I don't think you want the IMAX _projector_ lens, you want
| the IMAX _camera_ lens. I don 't think it works exactly
| "backwards" where a lens designed for the limited purpose of
| projecting onto a known static plane is what is best to actually
| acquire the images (?)!
| globular-toast wrote:
| The camera lens wouldn't produce the fisheye effect which they
| seem to enjoy. I don't think the camera lens would be any
| different to a high-end still photograph lens. Using a
| projector lens is the novelty here.
| buildbot wrote:
| It does work, but you are right that the optimization is
| definitely different.
|
| I think imax lenses are easily 5-6 figures unfortunately. Edit:
| It was a lens apparently, wow. It doesn't look like any of the
| IMAX lenses I can find online!
| anonu wrote:
| I actually think this was mislabeled in the video. It appears
| to be a camera lens - not a projector lens.
| kabes wrote:
| No, this is definitely the projector lens.
| Hnrobert42 wrote:
| The photographer in the video say it is a projector lens. He
| could be wrong, but it is what he claims.
| supernova87a wrote:
| Looking at some stories online, it looks like the actual
| camera lens looks much more normal sized:
|
| https://theasc.com/ac_magazine/August2012/DarkKnightRises/i
| m...
|
| https://www.premiumbeat.com/blog/you-cant-afford-this-
| expens...
|
| https://airandspace.si.edu/collection-objects/lens-100mm-
| mov...
|
| Methinks the projection lens is so oddly shaped to function
| with the curved theater screen, etc. and is not what is
| used to take the images.
| aaronbrethorst wrote:
| I loathe that stupid YouTube face that they all make.
|
| https://news.avclub.com/why-does-everyone-on-youtube-make-th...
| smcl wrote:
| Immortalised in this Rob Whisman tweet
| https://twitter.com/robwhisman/status/735281634656669696?lan...
| waiseristy wrote:
| One must have the almighty algorithms odd face fetish blessing
| Cthulhu_ wrote:
| It's not even the algorithms themselves, it's human behaviour
| and the magic "engagement" metric.
|
| Of course, it's also a self-reinforcing thing; there's
| articles telling people to put reaction faces on their
| preview images to increase engagement, there's articles
| telling people to use jump cuts, enthousiastic / shouty
| voices, certain microphone / camera setups, etc. Thousands of
| "do this ONE TRICK to boost your engagement on youtube by
| 0.34%" kind of articles and tutorials, trying to cargo cult
| aspiring video makers into doing the same thing that some of
| the top youtubers do.
|
| I'll stick to my series of disembodied hamhands and Scottish
| space nerds, thank you.
| dkdbejwi383 wrote:
| I hate the jump cuts. It's just distracting when a sentence
| has been spliced together from four or five takes (or maybe
| just two which they alternate between).
|
| It's as distracting. And hard to follow. As it would be. To
| read a sentence. That has had full stops added. All over
| the place. Like this.
| alex_duf wrote:
| scottish space nerds? I'm interested!
| Ivoah wrote:
| Presumably referring to Scott Manley:
| https://www.youtube.com/channel/UCxzC4EngIsMrPmbm6Nxvb-A
| yreg wrote:
| I'm more bothered by the seo text. It keeps repeating the same
| thing, similar to some autogenerated spammy website.
|
| cmd + f `huge .* lens` -> 7 results
| nitrogen wrote:
| Why does everyone feel the need to screw with scrolling (the
| avclub link scrolls much faster and weirder than the Firefox
| Android default)? It's disorienting.
| TwoBit wrote:
| Because they read some blog post about this cool thing you
| can do...
| scotty79 wrote:
| Funny how advertisement on this post about "youtube" face shows
| the photo from this article https://news.avclub.com/rudy-
| giuliani-accidentally-leaves-vo...
| Solocomplex wrote:
| Well? Did you $$engage with the content$$?
| mongol wrote:
| For me, those faces signals that the video is garbage.
| jedimastert wrote:
| Trying to get as many eyes on videos as possible has no
| correlation with the quality of video.
| second--shift wrote:
| The idea is interesting but as a side note, why does every web
| site try to ask me to sign up for their newsletter as I'm moving
| to close the tab? Why did this trigger/event end up in browser
| spec? Biggest anti-feature ever.
| [deleted]
| hnarn wrote:
| > It's pretty gorilla. Very, very gorilla, but it works.
|
| I've never heard this expression before. Does he mean "guerilla",
| as in "improvised"?
| Bayart wrote:
| There's a guy called Mathieu Stern who's got an entire Youtube
| channel [1] dedicated to exotic lenses.
|
| [1] https://www.youtube.com/channel/UCYX22a35sKhA0T6ee7uZfvg
| HenryBemis wrote:
| On his "front page" (latest mentioned video) he is talking
| about a lense called "BOKEH" and my mind immediately went to
| the movie "Bokeh" (https://www.imdb.com/title/tt3722062/) which
| is a great Drama/Sci-fi film, and a standing glorifying ad of
| Iceland's eerie and majestic scenery/landscapes. If you like
| sci-fi, give find it
| lm28469 wrote:
| "bokeh" isn't the name of the lens:
| https://en.m.wikipedia.org/wiki/Bokeh
| wut42 wrote:
| Yes, the lens is "Kipronar 105mm f1.9". It is also a
| projector lens, but you can use it on DSLRs and it makes a
| wonderful "swirly" bokeh.
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(page generated 2021-01-07 23:03 UTC)