Photography Of The Future (Terapixel Technology!)

A guy called Michael, recently replied to a post of mine and said 'How many
megapixels do we need?'. I thought this was a very good point, and made me
think a bit. (Bear with me on this.)

Resolution is something which will constantly increase, just like RAM and
Processor Speed of computers. If I remember correctly, Bill Gates once said
something along the lines of '512k RAM is enough for anybody'.

So, when is enough, enough when it comes to megapixels?

Bigger resolution does generally create sharper images because there is more
information to start with, and is why some people shoot Medium and Large
Format. The biggest advantage, apart from this, is the fact it gives you
more power to crop in Photoshop, etc.

Before you start typing your replies, I know there are photographers in here
who are thinking 'why crop?', why not get the picture you want in the first
place? Well, picture this. You are a sports photographer and are sitting
at the boundaries. You have only one lens, which is a wide angle lens.

You ask, 'Why no telephoto lens? The answer is, 'Because you don't need
it!'

The reason why you don't need it is because you just shoot away covering the
whole scene you want to shoot, and crop the part of the photo you want
because you have a gigapixel, or terapixel body.

Then, because the rest of the camera is just as good, you can sit there for
90 minutes, let the camera continuously shoot for the length of the game at
120fps and just take the crop of the frame you want.

Of course, this not just limited to sports photography, you could sit
anywhere you want to get the photo you want.

Scary isn't it! Not because of the fact that this future technology is a
possibility, but because photography will no longer be fun!

 

Last year i bought a medium format mamiya on the grounds of image quality,
true it is good, but what i have found most is that when i use the waist
level finder instead of the prisum the image clatity in the view finder far
outstrips anything i have had before and helps me see and frame the photos i
take. I love the camera so much i will always reach for it before my 35mm
canon.

Thanks

Karl

 

Well, Karl, don't get me started on medium/large format of the future.

The digital equivalent will be on satellites. This means that it will be
possible to take photos of the world, and crop to the part you want!

Just a thought, but is there any reason why this technology doesn't already
exist, and is already being used by the government?

 

yeah, perspective. Not much call for photos of the wedding from above.

 

Isn't there an optic limit to what you can achieve this way? Just the same
way that you can't simply use ever more powerful multiplying lenses to boost
the magnification of a given size telescsope (though this is the fraudulent
basis of most consumer telescope power claims). The image loses clarity once
you get past a mathematically determined limit.

 

You going to use a lens in front of this magic camera of yours? One
with infinite resolution, no aberrations, perfect MTF? do you have a
catalog number for it?

 

Of course any lens will resolve an image for an infinite
number of pixels. All you need is an infinite amount of
exposure time

Alan

 

Maybe an infinitely small pinhole lens?

 

From: "Matt"

Yeah, it's called atmosphere.
I keep hearing about the super sophisticated equipment used by the government
that lets a guy in a Colorado bunker watch some terrorist playing cards on his
back patio in Syria, all the while shouting at the screen, "Play the Jack!"
I call bullshit on that.

We are to believe that we can read a guy's cards from 100,000 feet, but we
can't find a tall Saudi in Afghanistan.

The government couldn't find their ass if it had a bell on it.

 

The answer is, as it always is to questions like this, it
depends on the application. There are certain scientific
imaging applications where the more pixels the better.
I suspect that astronomical observation may fall into this
category. Maybe crime investigation could benefit from
huge numbers of pixels in photos of crime scenes.

For ordinary snapshots, we probably have all the pixels
we need.

I'm not afraid of this at all. The great photographers don't
win their photographs in a lottery - they visualize a scene and
move themselves into a position to capture it. Great portrait
photographers don't just wait for a great expression on their
subject, they elicit what they want. Great landscape artists
don't just go outside and start shooting - they think about
light, perspective, color framing, and everything else.

You may think that sports photos are pretty cut and dried.
After all, a football field or basketball court is a fixed size.
But the great sports photographers get photos that random
camera snaps might never get, or get only in a million photos,
taking more time to view to find them than it takes to learn
to be a good photographer.

The analogy isn't perfect by any means, but I think we
won't get great photography from random snapshooting
for the same reason we get don't great literature from monkeys
on typewriters or great music from cats jumping on piano keys.

In other words, improvements in mechanics make things
easier to do but, by themselves, do not make great
photographs.

Alan

 

Matt escribio:

In sports photography, you need the telephoto lens in order to isolate
the subject from the background (blured background). You can't do that
with a wide-angle lens: even at f:2.8 the DOF is too much.

 

That's me... I'm a college professor... they pay me to make people think


In what follows, both the wave and the quantum properties of light are going
to get you. Read on...

A body with a 1-million-by-1-million array of pixels, you mean, or something
like that?

Let's do some rough back-of-the-envelope calculations.

Suppose the sensor is 2 inches (50 mm) square. (I'll admit you probably
want the camera to be bigger than 35 mm, but not gigantically bigger.)

Then each pixel is 50 nanometers square.

Guess what? That's 1/10 the wavelength of light! You won't get an image
anywhere *near* that sharp. Every photon will spread over some dozens of
pixels.

And then there's diffraction in the lens. Suppose you have an f/1 lens of
50 mm focal length. (You said wide angle.) Then its aperture is also 50 mm
and its Dawes limit (close to the Rayleigh limit) is 2.25 arc-seconds or
1/100000 radian (roughly). That translates to 500 nanometers.

So again, the resolution of your f/1 lens (even if someone invents a new f/1
lens design that is limited ONLY by diffraction, magically making all
aberrations go away) will be only 1/10 as good as your pixel array.

In practice, lenses are never diffraction limited at f/1. Designing a lens
is a matter of solving simultaneous equations and there hasn't been
tremendous progress in this recently. (There are real mathematical limits
on what can be done.) So allow another factor of 10 for the resolution to
be worse than that.

So now our 1,000,000-by-1,000,000-pixel array is now down to something like
10,000 by 10,000. That's a whopping 100 megapixels, just a factor of 10
more than we commonly have today.

In short -- Your dream sensor is going to be about like Technical Pan Film,
and your lens is going to be about like the best products presently
available from Nikon, Canon, or Zeiss.

It's fun to dream that all technology will advance the way silicon chips
have during the past 40 years. But that's just dreaming if you don't take
into account the underlying physics.


Michael Covington
Associate Director, Artificial Intelligence Center
The University of Georgia - www.ai.uga.edu/mc

 

Physics. There are real limits to the resolution you can get with a camera
of reasonable size (even ten feet in diameter) due to diffraction, and
there's also the unsteadiness of the air.

Why do we get better pictures of Jupiter with the Hubble Space Telescope
than with ground-based telescopes? Because we don't have to take pictures
through the air. A satellite trying to take a picture of the ground has the
same problem as a telescope trying to look up and out through the air. The
air is very unsteady. Resolution better than 0.5 arc-second is rarely
achievable regardless of telescope size, and much of the time, it's ten
times worse than that.

0.5 arc-second is roughly 1/400000 radian, or the resolution needed to read
a newspaper (distinguishing 0.5mm features) from 200 yards away.

 

Bingo. Diffraction limits. Exactly.

 

Not strictly true, but it does touch on another point. If you have tiny,
tiny pixels on the sensor, then it's going to take longer to get a
reasonable number of photons into each of them. Astronomers are already
familiar with this.

 

Oh dear.

"640k ought to be enough for anybody."

Resolution is not something which will constantly increase. Even with
an infinite pixel sensor you then become limited by the optics in front.

What's the application?

For my purposes it's when the size of the individual pixels, when
printed or displayed and then viewed at the appropriate/desired distance
exceeds the resolving capability of the viewer's eyes. Anything beyond
that is essentially wasted information except for the possibility of
noise reduction which could have been done ahead of time by using
fewer, larger, pixels in the sensor.

[snip of why we'd no longer need telephoto lenses]

At some point you will become limited by photon noise. After that you
don't want to make your sensing elements any smaller. Compare the noise
levels of an average point-n-shoot to those of a DSLR when both cameras
are at ISO 400 for an example of how smaller sensing elements affect
noise levels in the final image.

Since there is a minimum desireable limit for the size of a sensing
element--beyond which noise becomes impractical to deal with--there
is a limit as to how fine a detail the camera can resolve at the
sensor.

Let's assume for argument's sake that the limit is 1.0 microns for the
size of a sensing element--that's about 1/9 the size of some of the
elements used in some point-n-shoots. A square 1 gigapixel sensor would
measure about 3.1 centimeters across... not too bad in terms of size.
A square 1 terapixel sensor would measure about 1 meter across... not
something you want to use for a walk around town.

You would need sensor elements that are 0.036 microns across--less than
1/10 the size of the shortest light wavelengths they're supposed to
detect--in order for your 1 terapixel sensor to fit comfortably in a
35mm camera body.

Where are these facts of which you speak? I think you may have a lot
of reading and research ahead of you.

BJJB

 

<SNIP>

Very interesting observation.

And very plausable at some point in the future.

One thing I am waiting on is a camera that will mimic the performance
of different traditional film types at the touch of a button.

 

Only when they invent light that isn't made of waves or photons.

 

Glass just isn't up to the task.

 

you could have 4 rpogrammable shutter release buttons,
one for each style:
ektachrome, velvia, ...