Slashdot Mirror
The Lytro Camera: Impressive Technology and Some Big Drawbacks
waderoush writes "The venture backers behind Lytro, the Silicon Valley startup that just released its new light field camera, say the device will upend consumer photography the way the iPhone upended the mobile business. This review takes that assertion at face value, enumerating the features that made the iPhone an overnight success and asking whether the Lytro camera and its refocusable 'living pictures' offer consumers an equivalent set of advantages. The verdict: not yet. But while the first Lytro model may not an overnight success, light field cameras and refocusable images are just the first taste of a revolution in computational photography that's going to change the way consumers think about pictures."
Right now, it seems like the majority of Lytro pictures are technology demos, a fire hydrant in the foreground and a building in the background, or some equivalent, which just invites you to click both and move on. You can just hear the enthusiastic early adopter in the background of these pictures saying "OK, _now_ click the building! Whoa! Cool, huh?!". These shots are, to my mind, the photographic equivalent of arrows or spears coming out towards the audience in early 3D movies. Gimmicks which break the fourth wall, saying "Hey, remember, you're looking at a Lytro (tm) image, not just anything!".
I can't wait for real photographers and artists to actually find situations, styles and aesthetics where Lytro sorts of cameras can be used in a way that both effectively uses the new capabilities of the format _and_ produces something artistically and aesthetically wonderful. I think the technology has a ways to go, but right now, the biggest problem facing Lytro (and light field photography) is that it's a new medium that nobody has a clue how to use effectively.
Until we reach that point where people see a great Lytro picture and actually feel inspired, it's going to be tough to sell what is currently a low-spec camera with one big gimmick. So, if you want Lytro to take off, buy one for the craziest artist you know.
Seems Xconomy can't decide whether they like it or not:
The original title seems to have been "The Lytro Camera is no iPhone but it's revolutionary anyway".
going by the URL fragment:
the-lytro-camera-is-no-iphone-but-its-revolutionary-anyway
The current title is the less positive "The Lytro Camera Is Revolutionary, But Itâ(TM)s No iPhone" (Note: Not being an iPhone is a negative in a Stevebot's eyes.)
I'm not a lawyer, but I play one on the Internet. Blog
The capabilities of light field cameras have that fun 'technology indistinguishable from magic' touch to them that the impressive-but-evolutionary spec bumps of markedly superior conventional digital cameras don't(It's like playing with your favorite eccentric retro computer from before the Great Standardization: at this point, anything that old is a painfully limited toy; but it is different. Your top-of-the-line-screaming-monster of a PC, on the other hand, is brutally capable and impressively cheap; but practically point-for-point familiar to the p90 running Windows95, with all the performance related numbers bumped by a few decimal places).
Unfortunately, though, the move to release it at a (barely) 'consumer toy' price point really led to a product slightly too compromised to be useful: The optics you need for the light field capture eat so much of the sensor's available resolution that the resolution of the images you can get out of the thing is hovering slightly below 1 megapixel. Yes, the ability to spit out that paltry image at all sorts of focuses, after the fact, is damn cool; but for $500, you could get a high end P&S that could iterate through a series of 10MP shots at different focus points, at time of shooting in a few seconds, netting much of the benefit along with resolutions that wouldn't be ashamed to show up on a $20 webcam.
I'd love to see the same technology applied at a price point and form factor where the sheer sacrifice of available pixels wouldn't be so keenly felt.
DP Review has a review of this camera. It sounds like it has a long way to go. Due to the way lightfield works, the final resolution is fairly low, in this case only 1024x1024. I don't know if there's really a way around it, since they're substituting resolution for the depth of field focus feature.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
...that's going to change the way consumers think about pictures.
You're overestimating the average consumer: You believe they think prior to taking a picture. Having gone through enough cell phones left abandoned and dropped off at the lost in found before finally pressing 'm' in the phone book and calling their mom to say they lost their phone at my workplace... I can say with a fair degree of confidence most people take pictures of themselves, themselves with friends, more pictures of themselves and... (guys only)... pictures of inanimate objects that they never share or send to anyone. Ever. They're usually things like sign posts, car wheels (not actual cars, this would be too obvious), or random corners of buildings. From this, I can deduce that no actual thinking occurs for at least 95% of your everyday consumer's use of a camera.
#fuckbeta #iamslashdot #dicemustdie
My first thought was that it could be great for video; no need to bother with precise focus while shooting if you can refocus when you edit. However, I'm guessing that it would require a huge data rate.
For those more interested in the technology, Ren Ng's thesis is available on Lytro's website (at the bottom of the "Science Inside" page). I read much of the thesis at it the other day after reading an article about the camera in the New York Times. It's a well written thesis and explains the technology in a few simple ways and more rigoroursly.
The best explaination to me was that the microlens array is effectively reimaging the lens onto a small array of pixels under each microlens. (The micolens is placed at the usual focal plane of the camera and the # of microlenses is what determines the resolution). Each pixel therefore sees only a small aperture of the lens. A small aperture gives a very large depth of field. You could just use one pixel under each microlens to create an image with a large depth of field, but you'd be throwing away a lot of light. You can be more clever, however, and reconstruct from all those small aperture images the image at any focus. At different focuses, the light from any location is shared among multiple microlenses. (i.e, it's out of focus - so it's blurred at the focal plane). However, it's not out of focus at the pixels, since remember each pixel only sees a small aperture and has a large depth of field. It's then just a matter of adding the right pixels together to create an in-focus image at any effective focal plane.
Many people have noticed in the online samples that you can't focus clearly on far-away objects; they sorta get sharper, but not anywhere as sharp as foreground details. So that awesome picture of you on top of a mountain? You'll be nice and sharp, but the background never will be. Kind of spoils it, when the whole point is to be able to click and have one or the other be super sharp, right?
Also, it needs absurd amounts of light according to Gizmodo, or image noise becomes horrendous. Which is not surprising, given how hard Nikon and Canon are pushing the edge of what's possible in their sensors + image processors, and how small the individual lenses are. Great for sunny places. Not so much for indoors.
Please help metamoderate.
Part of what makes 3d movies look fake is that the viewer cannot focus on anything other than what is "in focus" as per the Director. I imagine it would be possible to use this technology paired with some sort of eye tracking tech (which also exists). This would move us a step closer toward a more realistic immersion.
Why do we need "focus" at all? Why not have photographs where everything is in focus? Depth of field is an artifact of lenses, whether they're in your eye or in your camera.
Focus can be used in composition to guide the viewer to the important elements in the story. Just as "left", "up","down", etc. define the field of view, so does focus.
Let's list some of the significant drawbacks of this first version which we can realistically chalk up as a technology demo:
* Camera is shaped weird and appears awkward to use. If form follows function, I'm not sure what the function is.
* Cheap last-gen LCD display.
* Output is only 1MP (1024x1024).
* Sensor is really small
* Lens is cheap
* Limited depth of field
* Raw light fields have to be sent to Lytro server for processing
* Only a handful of focus points can be chosen
* In focus range is limited
* Photos are converted into lame Flash animations
Now, let's re-imagine this as a serious photographers tool a few years down the road:
* It's a DSLR with real interchanegable lenses and huge hi-rez LCD display
* Let's say the camera can even magically switch from "classic" to light field mode with a toggle switch.
* Huge full frame sensor allowing light field output at 6+MP with high dynamic range and low noise at high ISOs
* Depth of field choices much broader and limited only by lens chosen
* Effective focus range is much improved
* Raw lightfield processing can be done on your local computer, allowing precise control over number and position of focus layers. Alternately, assuming processing speed is available, perhaps focusing points can be chosen in real-time within the finished image blob.
* Output as multiple jpegs, flash or HTML5, etc.
Now what?
Well, you still have these limitations if you use light fields:
* You're basically giving up some amount of image resolution for the ability to focus after the fact. DSLRs and even consumer cameras already have excellent auto-focus modes that when used properly generally nail focus in decent light. It's not the biggest or even second biggest problem I see in photos online. Bad composition and inadequate lighting are generally much bigger problems.
* If you chose the wrong focus point when shooting, sure you can fix your mistake, but if focus is off due to camera shake or motion blur, you're SOL.
* It's basically useless in images with large depths of field (think large landscapes where everything is essentially in focus)
* Makes no difference on a printed page, except you have one more tweak available during editing.
* Still gimmicky. After everyone has played around with a few of these photos interactively, they're bored and move on.
The Lytro camera has special optics that basically separates the light entering the lens from different angles. Knowing the rough angle of the light rays allows you to combine them in different ways to change the focal length of the image, as opposed to a traditional camera, in which they are permanently combined as the CCD captures the light at a set focal length. This comes with a trade-offs as light from each set of angles is essentially captured as a separate image, giving you say 12x12 sub images on the CCD, so the resolution of each sub-image is much lower than you would get using the full CCD for an image.
Since Ren Ng published his seminal paper making the connection between refocusing a light-feild and Fourier Slice theory, there has been additional work which shows that you can achieve the same thing using a simple filter, rather than a whole new set of optics. The benefit of this is that it is cheaper to manufacture, and you can easily switch out the filter to adjust the trade-off between image resolution and depth of field, but come with an additional cost of a slight loss of total light (due to the filter). Here is one of those papers.
There are two basic approaches. The first heterodynes the light (a filter acts as multiplication) such that light that enters at different angles is shifted to different frequencies. So with this approach you get "subimages" in the frequency domain rather than the spacial domain, which can be seperated and recombined in software. The result and trade-offs are essentially the same but with simpler hardware.
The other is based on refocusing as a deconvolution operation, but the filter modifies the point-spread-function of the camera, such that it's frequency response doesn't have any zeros, so you don't loose data at those frequencies like you would with a simple rectangular aperture.
Depth of field effects are considered part of the art of photography, much like amplifier distortion is part of the art of playing electric guitar. People pay a great deal for the capacity to get *narrower* depth of field: compare the price of Canon's 85mm f/1.8 and f/1.2 lenses. People most often buy the f/1.2 as a very very narrow depth of field portrait lens, rather than a very very low-light lens. Other lenses are known for the particular way that they throw backgrounds out of focus -- Nikon will even sell you one where you can choose exactly how the background is defocuses.
I think this trend in photography is overblown (I don't see the appeal of portraits where half of one eye is out of focus), but there's no doubt that artistic manipulation of depth of field is a big part of the art.
The Lytro takes still pictures, and can take 350 pictures in the 8 GB model, and 750 pictures in the 16 GB model.
Yes. It's kind of ridiculous. Most consumer cameras on the market allow a user-supplied CF or SD card, and the differentiating factor between cameras is normally photographic capabilities/image quality, storage is cheap, and 8gb of flash memory is not $100; the "amount of storage is built into the camera" being fixed is highly irregular; it also means I can't use a card reader to easily transfer data -- hooking up USB cables and trying to figure out any driver requirements is quite inconvenient.
The minimum I use these days are 32 gigabyte cards; with only 16gb, it would actually be necessary to frequently delete pictures to make room for more, instead of just swapping flash cards.
Also, flash cards have limited program-erase cycles... which means the camera has a limited lifetime if used heavily. I suppose warranty will cover for some time storage failure due to heavy picture taking activity wearing out the flash?
No, it's not, it's a useful word. It generally refers to a hobbyist who has the money/dedication to use genuinely professional equipment. For example, I don't play guitar for a living, but I do own a guitar and amplifier that would be more than suitable for a professional session musician. None of "amateur, hobbyist, enthusiast" conveys that. The marketing side of it is that companies have started to target those people as a sector in their own right, for instance Canon tend to make a range of cameras that have the same features as their high-end professional models, but with plastic rather than alloy bodies so not really suitable for a photojournalist in the field. Prosumer describes that quite nicely.
It's a single photosensor. The lens array and maths are doing the hard work. Therefore, although the data processing requirements may be very data intensive, the actual image should be the same, or very close to the same, as an image taken without the lens array. The maths should be implementable fully in hardware such that all processing can be done on camera at video speeds, so there is no reason that this couldn't be done. The issue would be making a cohesive focal point between frames. Having to focus a film frame-by-frame would take a lot of time and would be something only film studios might be willing to do, but would be too annoying for consumers.
Interestingly enough, the number of features on a device is as follows:
prosumer feature > consumer features > professional features.
The professional wants as few features/settings as possible but he does want to equipment to be of high quality. I actually created an application called 'Boom Recorder' http://www.vosgames.nl/products/BoomRecorder/ to record audio in the field for recording dialogue in movies and TV or live performances like concerts.
I created it because I used to be a prosumer and worked on beauty pageant and such. So I designed Boom Recorder for the prosumer market. I failed. Almost no prosumer bought one, because there were to few features, you could only record with it. However the professionals, the ones who make Hollywood blockbusters and big TV production and handle large events, they are the ones who love it; because it has so few features it just works.
Another example are video cameras. The prosumer one has lots of features and settings, way more than a consumer camera. But if you look at a professional digital film camera, there are hardly any features on it. I think professional only wants two knobs on a camera, the shutter angle (which changes the look of the film) and the start/stop button, all other settings which changes the look are on the lens.
As others already explained this would give unusually 'flat' pictures where depth of field has disappeared and the sense of distance with it, a problem already observed with tiny phone camera's.
This camera seems to go midway with many lenses for groups of pixels, the smaller those groups, the closer you get to your idea.
What I like about this concept is that the software allows for refocussing, they might very well already have a mode for maximum depth of field, i.e. all in focus.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
IIRC, it's an 11 megapixel sensor, to get a 1 megapixel image.
So, not TOO far off from 4k video, to get a low HD quality Lytro video.
If it meant a person who has more money than sense, why does it get applied to equipment?
I don't get the connection. But then again I have several grand worth of camera kit, and never plan on making a cent on it (though it would be nice). Why? Because I love the hobby. I know people who spent huge amounts of money on their cars, but will never race/drive professionally either. I know people, as well, who spent huge amounts of money on their computer and hardware, who will never use it for crunching data on anything more important than video games. I could go on, but won't. I don't see a lack of sense there.
There comes a point when pure consumer level stuff won't allow you to do what you want to do anymore, so you have to either quit or pony up some extra cash to get where you want. There is nothing wrong with this. And actually this has helped drive consumer level computer hardware for some time (enthusiast level chips and cards can be considered prosumer, to some extent).
In the future I can see myself spending at bit more on camera gear, when my skill eventually hits the hardware enforced limits, or I branch out into different areas. I have no problem with this, and I don't see it reflecting on my "sense", since I have the cash, and can spend it. If not on something I enjoy, then what should it be spent on?
A patriot must always be ready to defend his country against his government. -edward abbey