Stop the Megapixel Madness!

With this post, I officially declare myself an opponent of camera resolution. What? Oppose resolution? But resolution is inherently good, right? It's like being against ice cream or puppies. Well, what if you’re lactose intolerant? Or the puppy is a rabid pit-bull?

Even good things become bad if taken to excess. And that's why I hate megapixels. We have too damn many of them. Big resolution is a pain for some obvious reasons -- bigger files require bigger, more expensive memory cards and suck up more hard drive space. Yes, yes. I've heard those complaints. But if more megapixels produced better pictures, I wouldn't care about those downsides. Quality is worth paying more.

Here's the problem, though -- more megapixels produce WORSE pictures. Yes, worse. You may have heard or read my rants on this before. But now I have concrete, saddening proof.

Last week I met with folks from Pentax and saw their new K10D digital SLR, which immediately won my heart. Pentax is no Canon or Nikon, but it makes very respectable little SLRs at good prices. If you don't have (realistic) pro aspirations (and most of us don't), Pentax is a great way to go. The K10D has Pentax's cool vibration reduction technology via an image sensor that "floats" in a magnetic field so that camera jiggles don't cause it to move around. (The technology premiered in the K100D and works great, according to my tests.)

But the K10D also has other fantastic features. For the first time, Pentax has attached a name to its image sensor: The Pentax Real IMage Engine. OK, it's a clunky name, but it has a nice acronym -- PRIME -- which undoubtedly came first. Why didn't Pentax name their processors before? Because they weren't THEIR processors. They just bought 'em from a chipmaker. (They wouldn't tell me which one.) One of the coolest things about PRIME is that it takes DDR2 memory. What does that mean? Unlimited shooting. Press the shutter, and the camera keeps taking pictures until the memory card fills up. I'm not certain, but I don't think ANY other camera does this.

Another cool thing -- a very sophisticated analog to digital converter. This takes the gobbledygook from the sensor and makes it into a package of nice ones and zeros for the camera to process. Analog has a virtually infinite range of values, and every time you convert it to nice little ones and zeros, you make some compromises in accuracy. But the K10D doesn't make many. It has a 22-bit converter -- meaning it interprets 2 to the 22nd power shades of meaning. Its previous cameras had a 12-bit converter -- ten orders of magnitude less refined.

There's just one problem with the K10D: Its 10-megapixel sensor. This problem can be measured. In low-light shooting, it makes the K10D only half as good as Pentax's old six megapixel K100D. While the K100D goes to ISO 3200 sensitivity, the K10D can only go to ISO 1600. Pentax confirms that the sensor is the problem. So, new processor, new digital-to-analog converter, and worse low-light performance. That's how much damage comes from trying to squeeze an extra four million photodiodes onto a sensor of the same size. They are so tiny and receive so little light that you need all this new processing power just to get an image that is not quite as good as that from the entry-level camera. Oh, what a shame. So now, I get almost twice as many pixels, but they are fuzzier. So I can make giant prints that look like they are growing mold, or I can hide the fuzz by making prints that are as small as or smaller than those from the 6-megapixel camera.

The K10D certainly has some benefits over the K100D. Speed for sure, and possibly better color processing - which the K100D badly needs on long-exposure shots. (We'll have to wait and see the K10D to know for sure.) But it's so sad that that one of the new camera's "features," the resolution, is actually a drawback.

Comments

[John Ireland]

Wow. I have never read an explanation so concise. I have been chasing the increased pixel-count in a mega way myself. My suspicions that low light performance was somehow connected are now confirmed! Thanks. And great glasses. :-)