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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.
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.
"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.
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.
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?
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.
"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?