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What to Fight Over After Megapixels?
NewScientist has a quick look at where the digital image crowd is headed now that the megapixel wars are drawing to a close. Looks like an emphasis on low-light performance and color accuracy in addition to fun software tools are the new hotness. "For years, consumers have been sold digital cameras largely on the basis of one number - the megapixels crammed onto its image sensor. But recently an industry bigwig admitted that squeezing in ever more resolution has become meaningless. Akira Watanabe, head of Olympus' SLR planning department, said that 12 megapixels is plenty for most photography purposes and that his company will henceforth be focusing on improving color accuracy and low-light performance."
The megapixel wars may be drawing to a close, but they sure aren't doing it at 12 mp. Canon's 50D prvides 15mp in an APS-C sensor size, which is pretty tight, but users are achieving excellent results at that density... it just takes decent lenses, of which there are plenty in the Canon line.
15mp in APS-C format is a square sensel of about 4.6 m.
Canon's 5DmkII, on the other hand, is a full frame sensor, and it sports a whopping 21 mp... and does so by only going to 6.4 m, so there's quite a bit of room left there.
The 50D's got some noise issues, but the 5DmkII is a quiet design and they've clearly got some room to go.
So I think Olympus is actually saying that they can't, or don't want to, compete in the remaining space in the megapixel wars; withdrawal, if you will, rather than an actual end.
I've fallen off your lawn, and I can't get up.
That not surprising. Look at the Amazon reviews for any camera with a huge megapixel count, like the Canon G-10, and you'll see dozens of people complaining that, yes, the megapixels are nice, but the sensor may be noisy or the colours may be off. Too bad the industry didn't give more attention to accuracy earlier. I'd be happy to have a mere 7 megapixels if noise is seriously minimized.
"12 megapixels should be enough for anybody." - Akira Watanabe
Reviewing just the first hour of video games.
I suspect there will be a need for quite some time, for some purposes, to keep increasing the resolution. Usage (at least in some subset of people) will adapt and innovate. After all, if all the digital camera was for was to replace those 4x6 prints you all have in your photo albums, 3 MP would have been the end of it.
The accuracy of the human eye is such that you can only distinguish ~4000 pixels in a line while still being able to see the whole picture. 4000x4000=16 megapixels for a square image, or 12 megapixels for a 4:3 aspect ratio picture. Having more resolution than that is only useful if you are going to take part of the image and blow it up or otherwise focus on just a part of the image. So yes, once they achieve 12 megapixels CCDs, they should focus on something else, like speed for example. I have several pictures of "the couch where my daughter was a second ago" because my Nikon Coolpix inserts a huge delay between the time I push the button and the time the picture is actually recorded. Color accuracy would be nice too, or perhaps doing something about the graininess the CCDs seem to exhibit in low light conditions.
I've abandoned my search for truth; now I'm just looking for some useful delusions.
As was the case in the 35mm film days, the cameras that are best are the ones with the good lenses and good auto focus mechanisms. Secondary are good light meters. The pixel density is definitely high enough at 12M. At the start of digital photography, the CCD was definitely the primary bottleneck for picture quality. But those days are definitively over.
Optical SVG - the ultimate! Forget pixels. Have cameras sketch accurate SVGs of a scene with the ability to show or print at any resolution.
Good luck with that one. It's a lot harder than it sounds. Try tracing a simple 2-color bitmap in Inkscape sometime and zoom in real close. Now try tracing a full-color, full page photograph in the maximum number of colors possible.
Oh, BTW, hope you got lots of RAM and time to wait....
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1. Small phyiscal size (I wanna slip it in my pocket).
3. Good telephoto lens.
I think those two are mutually exclusive.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
"Fighting over megapixels" -- for someone who knows basics of photography, this is like fighting over which laptop comes with more preinstalled software tools, or number of features a text editor has. Like, there is *some* point of the discussion up to a certain level, and not much after that, and definitely nowadays this is not the most important factor for a decision which laptop to buy. The "megapixel wars" have ceased a long, long time ago in most of photography-related forums.
Except for professionals, 10MP and more is something like audiophily. And definitely an overkill for a pocket camera, where you are much more likely to hit the resolution boundary of the optical system itself (this is why professional cameras tend to be rather large...). Even 3MP (which was standard years ago) is sufficient for many purposes (given a high quality of the lens).
For photographers, the main fetish was and remains The Lens. A good lens may cost an order of magnitude more than your camera body. In the times of analog film, people often referred to the camera body as "film box", disrespecting its features and extras, compared to the importance of selecting the right lens.
I think the whole "megapixel war" issue started because photography became very popular with digital cameras, however people were not yet aware of the more important points -- and started to project what they knew about image quality (i.e. resolution) to what cameras they buy.
Now the knowledge starts to slowly infiltrate the "casual" photographer community. Having a few cameras, they start to notice other things: quality of the lens, haptics (how the camera "feels" in your hands), stabiliser, reaction time (time between pressing the button and the camera making the photo) etc.
j.
When i last upgraded my camera, the megapixels didnt change much, thats not what i was interested it, but it went from a 3X to a 12X optical zoom, there is alot of stuff out there that is worth taking a picture of, but is too far away to get a decent picture of, obviously if you go much higher you are going to need a tripod, or better image stabalisation, so i wonder how long before people want better zooms for their holiday and wildlife snaps, with better image stabalisation to support it
For me the biggest problem in pt-and-shoots, and in DSLRs to a lesser extent, is not lack of megapixels, but the lack of performance in low-light. The latest D-SLRs from Canon and Nikon, the higher-end ones (not the entry level SLRs) are getting much better, but for the most part, low-light performance of the current CCDs sucks.
That's as good as anything to get a 1-data-point comparison on camera sensors. (http://en.wikipedia.org/wiki/Dynamic_range)
Real -quality- factors, such as low light performance, color accuracy, etc, are a lot harder to quantify.
dave
Digital cameras largely carry over the conventions of film, such as ISO film speed. But these notions that higher speed "film" equals noise/grain are going out the window, as newer cameras are able to achiever clean pictures that were impossible to do with film.
Similar notions go that exposure is rated the same way that film cameras did, such as stops above/below aperature+shutter speed.
Suppose if Digital cameras were invented without these notions of what film cameras did. Wouldn't there be a better way to measure aperature, shutter speed, exposure, film speed, etc than the conventions that we have now? Couldn't digital cameras redesign the scales so that they aren't measured in fractions of seconds or tenths of a decimal?
The cameras need built in AIs that talk to you.
"Beep! This image is framed poorly."
"Beep! The subject requires better lighting."
"Beep! The subject needs clothes. Seriously. This is not porn material."
"Beep! The current angle will not sufficiently capture the dark and depressive mood for which you were aiming. I have wirelessly ordered you some Zoloft."
"Beep! Wow, that's just... really... may I suggest a different hobby?"
"Beep! This camera will now self destruct to save your family, friends and the world in general from your mind numbingly boring vacation photography. You have 30 seconds to reach minimum safe distance."
What to Fight Over After Megapixels?
Simple. Gigapixels.
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although the megapixel count is still increasing, it's becoming less important than other aspects of the camera
For me compression is an issue.
The statement that 12 mega pixels is enough for general use has an information theoretic interpretation. namely for the standard lens fields of view and typical range of distance to target that there is no added information in having finer resolution. Or at least the amount of information useful to humans is diminshing.
Assuming this statement is true then it ought to be that the ideal photo compression algorithm produces the same size image file no matter how many pixels went into it. That is to say a lossy compression algorithm would only be discarding detail of no human interest.
This is not true, the compression does not seem to be getting better. This suggests that the compression algorithms in use are not scaling properly for increased pixels.
Hence more research is needed to find compression algorithms with this property.
I dislike high mega pixel cameras because they are increasing in stored picture size faster than my hard drives are keeping up. e.g. when I went from a 4 mega pixel camera to an 8 mega pixel camera my file sizes became 4 times larger. My internal disk drive did not become 4 times larger in that time so I had to start using external storage. It became harder to squeeze these onto ipods.
But you end up buying these 8 mega pixels ones because even though you might be happy with fewer megapixels, the 8 mega pixel ones take better pictures simply because they have better light sensors, greater sensitivity, anti-shake, and so-forth that the cheap 4 mega pixel cams lack.
Some drink at the fountain of knowledge. Others just gargle.
Here's a chart to see how many MPs you need for photo quality digital prints.
Of course, that doesn't take into consideration noise, dynamic range, or color accuracy of the sensor.
The dynamic range of our linear sensors is the weakest part of the chain. Film sucks compared to modern digital in all ways except their response curve: many films don't capture light levels in a linear way, so they can discriminate details in the clouds in a bright sky even while capturing details in the shadows. Almost all digital sensors are on the order of 9~12 stops of acceptable dynamic range, and they've been there for nearly a decade.
Cameras tend to expose for the midrange automatically. To avoid blowing the highlights, which is very visible on a screen or printout of our photos, we have to artificially adjust that exposure, called "stopping down," until we capture details in the highlights, at the expense of detail in the shadows.
There are some combinatorial techniques to achieving high dynamic range; you take multiple exposures and mathematically or artistically mix them to achieve both shadow and highlight details. But this technique is not well suited to movies or still-shots of moving scenes.
Sensors need to get a LOT better at achieving a dynamic range of 20 stops or more.
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P.S. - and an INDUSTRY STANDARD RAW file format!
"12 megapixels should be enough for anybody." - Akira Watanabe
For comparison, 1920x1080-pixel HDTV is about 4 Mpx: 2 Mpx for luma and about 2 for chroma. An 8x10 print at 150 lpi has a similar pixel count. True, more Mpx in a consumer product lets you do more digital zoom after the fact, but what else is it good for?
I can't tell you how many times I've looked at a picture, analog or digital, and wished I could turn a small part into a poster.
Back in the day, that's what they used large-format film for.
Imagine if a movie editor could decide, in post-production, to "zoom 10x closer" in on a subject?
Just because you can't benefit from them when viewing "full frame" doesn't make extra pixels worthless.
Besides, even if you aren't cropping, to emulate the resolution of 35mm at 100 a typical line-pair-per-mm resolution, you'll nominally need 5000 dots per inch, or 33 megapixels. I'd prefer 4x as many to handle worst-case situations. Now, in practice, how many of our photographs wind up as 2' x 3' posters? Not many. If the biggest you will ever enlarge is 1/3 of that, then your resolution can drop to 1/9th. Depending on how demanding you are, you won't need more than 4-16 megapixels to produce a nice 8"x12" print. Consumer- and pro- 16 megapixel cameras are here today.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Actually for professional looking photos, sensor size does matter, again as the result of basic physics. You can downsize the sensor all you want but you can't downsize the wavelength of visible light. Come on Pentax, Mamaiya, Rollie or somebody, please release an affordable digital medium format camera!
I mean *really* faster. I recently acquired a professional-grade digital SLR and was astonished to find that the "3d matrix motion sensitive autofocus tracking" or whatever it's called, wouldn't accurately track a dog chasing a ball. The camera would graciously show me the autofocus points of successive frames -- clumps of grass, small pebbles, a trash can, and occasionally the actual subject. It was somewhat surprising to me that, to get accurate focus of moving objects, I could get better results by turning off all the "moving object" settings and rely on my own targeting skills. With all the computer power at our disposal, the durned camera should be able to recognize, not just distance and color and lighting, but the *shape* of the object I first targeted, and then track that object for successive shots as it moves around on the screen.
I've ranted about this on other subjects, but it's worth a small rant here: stop making memory -- in this case the memory buffer -- a selling point to get you to pay for overpriced pro models. Memory is *cheap*. The first major company that puts a substantial memory buffer in all their models, enabling a significant number of continuous frames before writing to the card -- is going to clean up. I have a friend who not long ago bought a pair (his and hers) of high-end snapshot cameras (you know what I mean -- fixed lens but mechanical zoom and nice glass) only to find (while on vacation) that the write speed was so poor as to make them unusable in the field. I know, you can fix this a little with faster memory cards, but ram will always be orders-of-magnitude faster than mass storage. This is a cheap addition that makes a huge difference in the user experience.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Akira Watanabe is playing self-serving marketing games. It is not about any particular number of megapixels, it is about the size of the light well of each pixel, or "pixel density" if you will. That determines the dynamic range and sharpness per pixel. Mr. Watanabe's company has pushed that past their main competitors despite the fact that those competitors have larger number of megapixels in their top cameras. How is it possible? Sensor size. Let's look at some of the offerings today on the market (the smaller the density the better):
So yes, Olympus is now hitting 5+ MP/cm2 on their SLRs despite having much lower number of pixels than Canon with their 5DMkII, Sony A900, or Nikon D3X. This is because Olympus boxed themselves into a smaller sensor (4/3). All the posturing about how 12MP is enough is only designed to hide their shortsightedness.
(BTW, /. seriously needs to allow <pre> tags)
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