Megapixel Myth?
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- ItTango
Interesting article from a few years back.
http://www.nytimes.com/2007/02/0…
- lvl_130
login credentials please
- ItTango0
just for you, lvl_13:
For an industry that’s built on science, the technology world sure has its share of myths. Thousands of people believe that forwarding a certain e-mail message to 50 friends will bring great riches, that the gigahertz rating of a computer is a good comparative speed score, or that Bill Gates once said “640K of RAM ought to be enough for anybody.”
But one myth is so deeply ingrained, millions of people waste money on it every year. I’m referring, of course, to the Megapixel Myth.
It goes like this: “The more megapixels a camera has, the better the pictures.”
It’s a big fat lie. The camera companies and camera stores all know it, but they continue to exploit our misunderstanding. Advertisements declare a camera’s megapixel rating as though it’s a letter grade, implying that a 7-megapixel model is necessarily better than a 5-megapixel model.
A megapixel is one million tiny colored dots in a photo. It seems logical that more megapixels would mean a sharper photo. In truth, though, it could just mean a terrible photo made of more dots. A camera’s lens, circuitry and sensor — not to mention your mastery of lighting, composition and the camera’s controls — are far more important factors.
I can show you plenty of enlargements from a 4-megapixel camera that look much sharper and better than ones from an 8-megapixel model. Meanwhile, a camera with more megapixels usually costs more, and its photos fill up your memory card and hard drive much faster. And more densely packed pixels on a sensor chip means more heat, which can introduce speckles into low-light shots.
But you can repeat this lesson until you’re blue in the newspaper column, and some people still won’t believe you. They still worry that their 5-megapixel camera from 2005 is obsolete. They still feel sales pressure when shopping for new cameras.
So as the host of a TV series (“It’s All Geek to Me,” to begin in April on Discovery HD and the Science Channel), I thought I finally had a chance to settle this thing once and for all. At the climax of the camera episode, I would test the Megapixel Myth on camera, supplying visual proof for the world to see.
I created three versions of the same photograph, showing a cute baby with spiky hair in a rowboat. One was a 5-megapixel shot, one was 8 megapixels and one was 13.
I asked 291 Digital, a New York graphic imaging company whose clients include ad agencies and fashion companies, to print each one at a posterlike 16 by 24 inches. (They were digital C prints, printed on Durst Lambda at 400 dpi, if that means anything to you.)
We mounted the three prints on a wall in Union Square in Manhattan. Then, cameras rolling, we asked passers-by if they could see any difference.
A small crowd gathered, and several dozen people volunteered to take the test. They were allowed to mash their faces up against the print, step back and squint, whatever they liked.
Only one person correctly identified which were the low-, medium-, and high-resolution prints. Everybody else either guessed wrong or gave up, conceding that there was absolutely no difference.
I described the test on my blog (nytimes.com/pogue), confident that I would be hailed for blowing up the camera companies’ pet morsel of misinformation.
In the following days, 450 readers responded to the article. Many endorsed the test results, citing their own similar experiences.
But there was also an angry group who didn’t like my methods. They took issue with the way I produced the lower-resolution images: by using Adobe’s Photoshop software to subtract megapixels from the 13-megapixel shot.
“More ignorant rantings by the NYT,” went comment No. 206. “If you want to see the difference, take frames of the same scene using different cameras.”
These readers felt that “down-rezzing” a 13-megapixel photo tested only Photoshop’s pixel-subtraction techniques — not camera sensors.
I’m not entirely convinced. The Megapixel Myth suggests that you’ll see less detail in a 5-megapixel shot than a 13-megapixel one; how it gets down to 5 megapixels shouldn’t make much difference. Fewer dots is fewer dots.
Still, on the blog, I offered to repeat the test using more scientific methods.
The “use different cameras” suggestion, however, was out of the question. Different cameras have different lenses, sensors and circuitry — factors that do produce meaningful differences.
I challenged readers to devise a test that would isolate megapixels as the sole difference between the test photos — without involving Photoshop.
Ellis Vener came to the rescue.
“I am a professional photographer and a technical editor at Professional Photographer magazine,” his e-mail message began. “I’ll be happy to do the following test.”
Using a professional camera (the 16.7-megapixel Canon EOS-1Ds Mark II) in his studio, he would take three photos of the same subject, zooming out each time. Then, by cropping out the background until the subject filled the same amount of the frame in each shot, he would wind up with nearly identical photos at three different resolutions: 7 megapixels, 10 and 16.7. “Frankly, I’m interested in the results as well,” he wrote.
I gave him a green light for the new test.
His choice of subject also put to rest another objection to my original test. Instead of a smooth-skinned baby, Mr. Vener’s model was positively bristling with detail: curly hair, textured clothing, a vividly patterned background and a spectacular multicolored tattoo on a hairy arm.
We set up the new 16-by-24-inch enlargements on identical easels at a public library. (Why the library? Because it was warm, it was flooded with natural light and its director gave me permission.) Clipboard in hand, we conducted the test again.
Surprise, surprise: the results were the same. This time, out of about 50 test subjects, only three could say which photo was which.
So is the lesson, “Megapixels don’t matter?”
Not exactly.
First of all, having some extra megapixels can be extremely useful in one important situation: cropping. You can crop out unwanted background and still have enough pixels left for a decent print. (Blog comment No. 376, for example, imagines “a child’s face that looked priceless at the time the shot was taken — and it occupied 5 percent of the photo. For this rare occasion, it is worth being safe rather than sorry.”)
Of course, it’s better to get your composition right when you take the photo, but this is still a great trick to fall back on.
Megapixels may matter to professionals, too, especially those who produce photos for wall-size retail displays. And even in consumer cameras, there are certainly limits to the irrelevance of megapixels; my test went only to 16 by 24 inches, which is the biggest I figured most amateurs would go.
(As one reader put it: “Why not downsample your photo to 1 pixel by 1 pixel, and then print 16-by-24-foot pictures?” Well, yes, then you’d see a difference.)
The actual lesson, then, is this: “For the nonprofessional, five or six megapixels is plenty, even if you intend to make poster-size prints.”
Or, as comment No. 370 put it: “For the average consumer trying to decide between 5 megapixels and 8 megapixels on similar cameras, Mr. Pogue’s test might save them a little bit of money and a lot of hard-drive space.”
Unfortunately, blowing up the Megapixel Myth also takes away a convenient crutch for millions of camera shoppers. If you’re torn between two camera models, you now know that you shouldn’t use the megapixel rating as a handy one-digit comparison score.
So what replaces it? What other handy comparison grade is there?
Unfortunately, there’s no such thing. Take advice from your friends, take sample shots if you get a chance, and read the reviews at nytimes.com, cnet.com, dpreview.com and dcresource.com. What can I say? Life is rarely black and white; it’s far more often filled with shades of gray.
- eieio0
there is no "megapixel myth", megapixels do in fact effect the picture quality its just not that big a deal at the consumer level if you're taking 100 bucks difference or something.
- If you take into account the average printed picture size and what the naked eye can discern, this article makes sense.ItTango
- sense.ItTango
- to a digital imaging professional this article is full of truthyness and spineieio
- aren't they also digital imaging professionals? And isn't hyping 10mp over 6mp is also spin?ItTango
- this article was written to appeal to consumers sense that they are now informedeieio
- there's a difference between a myth and camera people hyping certain features for bigger saleseieio
- Well they clearly chose "Myth" to garner more readers.ItTango
- truthyness!!!!version3
- SteveJobs0
i agree. not a myth. the higher the megapixel, the better the image you'll have once you scale it down enough so that it actually is a clear, sharp image.
however, the need for this optimal scaled down size surely won't grow much more than the size of our monitors or whatever size is needed for magazine/billboard/etc. print. beyond that the extra megapixels only real value will be functional. that is, the ability to zoom in on an image an not lose that carity - so basically CSI's impossi-zoom becomes reality.
- ItTango0
I agree, the megapixel thing isn't bullshit, but I think many people are stuck on the "more mps make my photo better" school of thought. mps don't make up for crap lighting or lenses. To tell a consumer that the new 10mp Nikon will blow their 6mp Nikon out of the water is just plain dishonest.
- Projectile0
with a lens the size of those on a normal compact camera, anything above 5mpx is pretty much pointless imo.
haha my first camera was 3mpx.. but had "pro" mode where you could go up to 7!!!!! bearing in mind this was in 1999.. there was no such thing as a 7mpx sensor. I even tested it. Took the same photo with both of a deodorant can, and when you zoomed in, the detail level was still the same- just couldn't read the fine print
- vaxorcist0
For some people, DXO Mark sensor scores are the new megapixels
http://www.dxomark.com/index.php…
but really... good gear, actual talent, good subject, pick any 2
- wow, my D90 beats an EOS 1D Mark II N and 5D according to thisenfocusmedia
- check in various conditions... like low light... they do like D90 though... I like 5D m1vaxorcist
- akrokdesign0
maybe it's not a myth. more of being misinformed.
it's not like a reviewer says, but you probably don't need it if you already have a 5mega pixel camera.
- ayport0
Seems to me that it is the process by which an image is scaled up from its original dimensions is most important.
- quamb0
It's common sense really, though I guess people get caught up on the tech-stats.
A 1-megapixel camera compared to a 20-megapixel camera, obviously there is going to be a difference. Just like shooting on 8mm vs IMAX film. Seems for 90% of people, the sweet spot is around the 6-megapixel mark, anything more is kind of useless data.
The real con imo, are these cropped sensors being used and sold in "prosumer" SLR's.
- I prefer to have about 8MP then from there its all in the sensor and lens quality.ETM
- raf0
At some point sensor resolution isn't a problem anymore, it is when the lens becomes a bottleneck.
Not everyone realizes, lenses do have physical limitation as to how many lines of resolution they can deliver.
- sequoia0
the test also doesn't deal with color resolution and dynamic range, which are important features that are updated with every generation of a camera.
- identity0
It's not a myth - bigger is better
- version30
"lenses do have physical limitation as to how many lines of resolution they can deliver. "
what?!?!?!?!
i want to kick someone so hard right now- sounds like you hve anger management issues. take it easy dude.felizfeliz
- version30
- MTF is a factor of the lensesversion3
- http://www.tmworld.c…version3
- raf0
I strongly disagree with high ISO being a hype. I would easily trade MP for ISO.
Being able to shoot hand-held in low light is something that was beyond reach with 35mm film. Actually, good high ISO performance is the only reason I am planning to upgrade my 5D to 5D MkII.
- DoktorDavid0
Lighting; subject; skill; "eye" - the rules really don't change - I've seen some 5mp images that totally stopped me dead in my tracks and some 20mp of my own that I go "what the fuck was I thinking?"
