Wavy Lenses Extend Depth of Field in Digital Imaging

genegeek writes "On Feb 25 CDM Optics was awarded a patent for a new digital imaging system utilizing "Wavefront Coding" that produces images with 10-fold the depth of field of conventional lenses. The image itself is blurred until processed. Image examples are here."

Comments

Re:So

[Deth_Master]

So, just take a trip to the next space telescope we put out into space, once every couple of months to get the film from it.
I mean this has it's advantages, perhaps not to the average joe. I like analog photography too, but digital will work much better in getting images from space probes, satellites, and other far off devices, hell, even spy-planes, to another location really quickly.

Re:So

[egomaniac]

Basically what this is saying is that if I go out and get a new whiz-bang camera with this funky new lens, I will be able to take a picture almost as good as the pictures I take with my 30 year old Cannon AE-1, and not have the leeway of doing photo processing tricks in the darkroom.

You stick to your film. I'll stack my Nikon D1X against your 30-year-old camera any day of the week, personally. And that's not even top of the line anymore -- Canon has a new 11MP camera that puts any 35mm camera to shame.

Just because $300 consumer digicams are crap doesn't mean that digital hasn't already surpassed film. It's just a matter of making it affordable now.

So is my film scanner obsolete?

[Nom du Keyboard]

So what does this do to my nice film scanner? Does this make my digital photography image chain unusable with the new technology? It seems unlikely that there's a Photoshop import filter for the original negative.

And I'm always leary of adopting a new technology that is monopolized by a single provider.

What about the deep focus movies of the 50's?

[jlowery]

Does anybody remember the deep focus cinematography of Gregg Toland? How were those shots done?

Re:What about the deep focus movies of the 50's?

[NickFusion]

There were two approaches:

1) Throw a shitload of light on the scene (This is what they did for the effects work on "Darby O'Gill and the Little People..Peter Jackson eat your heart out)

2) Use a diopter, a lense that changes focal length split down the middle, so that half the image is at 20mm, and the other half is at 120mm (for instance). This was a trick pioneered by Orson Wells, I beleive.

Re:What about the deep focus movies of the 50's?

[jlowery]

Nope, wasn't small aperature. Both foreground and background were in focus.

Take a look at shots from "The Best Years of Our Lives" (1946)

BTW, Toland died in 1948, so I should have said movies of the 40's, not 50's.

Re:So

[burninginside]

if you want to talk megapixels tho there are about 20 million pixels in 35 mm film, there are digital backs for medium format cameras which match and surpass this but for the cost (usually 5k+) it's not in the price range of your average consumer, which probably wouldnt be willing to buy a medium format body either due to cost

Film and digital resolution comparisons

[JeremyR]

There are at least two experienced photographers (Rob Galbraith and Michael Reichmann) who feel that the 11-megapixel Canon EOS-1Ds delivers images with detail exceeding that of 35mm and approaching (in some cases besting) medium format film. They've published some very interesting comparisons:

http://www.robgalbraith.com/bins/content_page.as p? cid=7-4833-4853

http://www.luminous-landscape.com/reviews/camera s/ 1ds/1ds-field.shtml

This may just change someone's opinon on how digital compares to film. I know it made me rethink the "conventional wisdom" that many more pixels are needed to reproduce film detail.

Cheers,
Jeremy

Re:So

[deathcow]

I'm sorry to tell you, but you are just plain wrong. Does your camera exceed the laws of physics? Can your lenses somehow focus a point-like source of light to an abnormally small airy disc? The answer is NO.

Realize that the Canon 1Ds has pixels that are SMALLER than the airy disc size at almost all f/stops. You simply cannot achieve better resolution with the lenses available.

Believe what you want about your 135 film, but it takes APERTURE to shrink the airy disc and improve the true image resolution. As far as 35mm film goes, the 11 megapixel 1Ds can image ANYTHING that comes through the lens.

The same is true for my 6 megapixel D60, but only at smaller aperture f/stops.

NASA docking camera?

[Bazzargh]

havent been able to get to the site because of you lot bringing it down but... is this related to the technology used in NASA's docking cameras? I remember reading that they developed a camera that worked exactly as the /. story described, in order to combat the problem of losing focus on the target spacecraft during docking manoeuvers. The report I read was in New Scientist, probably 3 years ago?

I'd go and find it but NS archives are subscription only. I really ought to get round to subscribing, I buy it often enough...

-Baz

what is more interesting to me as a photographer..

[dbc]

... and I can't find out because the site is /.'ed :-(
is this: Can this technology be used to control (not just increase, but also decrease) depth of field at image processing time? More specifically, can I get selective focus *after* creating the image? In criticizing my own work, I ususally wish I had openned up for *less* depth of field. I realize that sports photographers don't have this problem :-) but some of us nature photographers do.

Re:Digital has better colour? What???

[b-baggins]

Actually, that's not true. Film captures color as realistically as the photochemicals can react to the incoming photons.

Noise floor and linearity

[Andy Dodd]

If anything, as other people posted, digital is closer to the "real thing".

One person mentioned that Fuji Velvia is great for landscapes but murders skin tones. This is because the sensitivity curve of a digital can be easily optimized, while it's very difficult to tweak the sensitivity and linearity of films based on chemical reactions.

As to rounding to the nearest bit - There's a lower limit in both electronic and film recording of the precision that a light level can be recorded which is distinguishable from noise. This is called the "noise floor" - Use enough bits, and then all the bit roundoffs will be well below the noise floor of even film media. (Which does indeed have a noise floor, just as digitals do. The nice thing about digitals is that with improved electronics and sensors, the noise floor of the sensor is dropping while film is staying the same. One of the things "pro" digitals are known for is having far less noise than lower-end digitals, and those improvements are constantly moving down to the consumer level.)

And for those that WANT the nonlinearities/quirks of film - All a camera manufacturer has to do is model the nonlinearities of major film types and then they can easily be emulated, just like guitar amps that use modeling techniques to emulate older units.

Re:University site with original papers

[Compuser]

Thanks for the links. It seems this system has a
downside, namely it introduces its own artefacts,
similar to ghosting. Look at http://www.colorado.edu/isl/intimages/focusinv.htm l
and this will become clear. I wonder if this is
inherent in their technique or just the imperfections
of "1.0 release" of their tech.