Digital photo lenses that distort

I like fine camera lenses, but the best quality are very expensive. There are many things that are hard to do in a good lens -- you want a sharp image, of course, over the full flat plane. Over the whole image plane you want low flare, high contrast and low chromatic abberation (ie. red and blue focus in the same spot.) And you want low distortions.

Most camera lenses try to be "rectilinear." That means they try to make a straight line straight in the image. This isn't actually natural, due to perspective straight lines are not straight.

So I wonder if we might soon see a new lens where no effort is made to fix distortions or make the image rectilinear, and all effort goes into the other factors. You are thus expected, with every image, to do digital post-processing to get a non-distorted rectilinear image. That will mean some small loss of image quality at the edges of the image, but probably a less distorted image than ordinary lens physics can deliver -- and a lot less cost -- in exchange.

Of course, this would primarily be for digital cameras, but a film user could also use the lens if they planned to scan their film for digital processing, as most do these days.

Down the road, each lens might contain within it the specifics of its own particular distortions, and the camera might be able to fetch this and either process directly or store it with the image for post-processing. Indeed, the lens might be a cheaply made lens with distortions due to the poor quality elements, or it might be a fine lens with deliberate distortions. (I have wondered if some P&S digicams might be doing this already.)

Certain types of chromatic abberation might also be treated this way, if they simply change where the light comes to focus, and don't blur it. The camera would know that the red light is one pixel to the left when it creates the image.

Comments

Well, you've beaten me to it. I've been thinking of correcting the chromatic aberration this way just last night.

Chromatic aberration is a good candidate, cause it is minute, and making a minute correction can't do much damage.

As for straight lines ... barrel distortion is a pain (I hate it). But ... well, you pretty much get the problems of doing near 1:1 ratio image stretching. And that is not a good thing to do. But maybe you're right, maybe it would pay off.

At this point in time, image processors in digicams are simply not powerful enough to do all this. But - they're getting there.

Now, how did I end up on your page? By trying to solve the same problem - distortion. Was hoping there is a camera that offers what I want. And that is:

I don't care that much for megapixels. And there will be plenty more, there is absolutely no need to use them all. Then think how the so called smart zoom works when you choose to store images at a non-maximum resolution. You have a losless digital zoom. Now, why start using it when you reach the end of the optical zoom? Hell, I want to use it immediately. As soon as I 'zoom' away from the wide end, I want to 'crop-in' and stop using the problematic outer rim, the corners. And, hey, as typical zoom starts reducing the aperture, I gain in that department also.

The behavior can be made very customizable, or it can be made completely seamless. Just as any other degree of freedom (or a pair of those) we have in photography.

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