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Comment by wtallis | Hacker News Reader

It's really disappointing to see even engadget disparaging HDR because they think it's the same thing as tone-mapping, and because they think tone-mapping always produces freaky results. All HDR really is is a technique for gathering more information that can be post-processed.

And, from what little we've seen of HDR+auto tone-mapping on the iPhone, it could be the harbinger not of rampant pyschedelic tone-mapping, but of more reserved and tasteful tone-mapping.

One thing I'm willing to bet on, though, is that this will elicit a lot of criticism from the people who've fallen in love with the limitations of current cinematographic techniques. They'll complain about how you can actually see stuff in shadows, and that the lens flare doesn't do enough to obscure the subject, all without realizing that this advance merely makes those things optional.

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" ... and that the lens flare doesn't do enough to obscure the subject, all without realizing that this advance merely makes those things optional."

The funny thing is, lens flare is like tape hiss in audio recording; it's an artifact of a given capturing technology, not intrinsic to the thing being captured. On the one hand, it should just go away as recording technology improves, since you don't experience lens flare when you see something with your own eyes, yet, unlike tape hiss, it has become some sort of token indicator of "realism" (especially in CG movies).

Some people will look at HDR video and complain that, like HDR still shots, it doesn't look real, as if something viewed through a recording intermediary could ever properly look real.

You can experience lens flare in your eye because you have two lens in your eyes. http://en.wikipedia.org/wiki/Lens_flare

Close your eyes and only let a slight open aperture to your eyes, you will experience all kinds of interesting effects made by your eye lashes too.

Totally real, like HDR(we see far more dynamic range than digital cameras, and have exponential, not linear sensors).

Interesting. I'm aware of visual distortion when squinting, but never thought about lens flare under typical eyeball conditions. Perhaps it's a phenomenon that the mind filters out, or is so obvious I never think about it. (Now I'll have to pay attention.)

Do you think the traditional cinema lens flare mimics what the naked eye sees? I'd think not.

A problem with pure CG movies is that they feel sterile. Producers add in visual distortions to make it feel real, but what they're adding is merely what's familiar (that is, the results of traditional lens and film that has become accepted as a stand-in for real), not what a naked eye might normally experience. But it's enough to make people feel more comfortable with what they're seeing.

Using spatial dithering and the iphone 4's retina display, you could make an app that could display HDR and still have the resolution of the old iphone. Throw in temporal dithering if it was something like a static photo viewer, and you would have a pretty massive range.

That would just increase the resolution. The real problem is that the device is way too dark to display the levels of radiance you see on a bright day. Tone-mapping has to be used to bring those levels down, and there is no "correct" way to do that - one has to play with settings.

It wouldn't increase the resolution, it would increase the dynamic range; for two shots with different exposure you would do 4 pixels white if both were white, two pixels white if one was full white and the other full black, etc. (your flat panel probably already uses a similar approach to get roughly 8bits of overall color-depth out of 7bit elements)

I meant intensity resolution (or color depth, as you say). Dynamic range is something else - it is the interval [darkest, brightest], or their ratio if you prefer.

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