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Does a lens exist

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littleprince

Golden Member
Jan 4, 2001
1,339
1
81
If everything is in focus at f14, than your sensor is the size of a pin...

Anyways, back to the OP. Human eyes suck at it. I'd have to say cameras to a much better job.

To do it best, a wide angle lens, at the smallest aperature and a small digital sensor should do the trick.

Originally posted by: Snagle
Originally posted by: MillionaireNextDoor
A friend's friend in Stanford has such a lens. Cost him $10k to build it with his technique. No one else makes them as far as I know.

Huh? I can set any of my lenses to F14 and get everything in the frame in focus.

 

n yusef

Platinum Member
Feb 20, 2005
2,158
1
0
Originally posted by: DigDug
Yuck. Depth of field is what makes things so interesting. Point and shoots always use infinity focus. That's pictures from those things are so damn boring.

No. Actually fixed focus point and shoot lense are usually focussed at the hyperfocal distance to obtain the most DoF possible.
 

Mo0o

Lifer
Jul 31, 2001
24,227
3
76
Actually the human eye can only keep a tiny portion of your field of vision in focus at any given time
 

Rubycon

Madame President
Aug 10, 2005
17,768
485
126
Originally posted by: littleprince
Anyways, back to the OP. Human eyes suck at it. I'd have to say cameras to a much better job.

So you're implying that my eyes aren't human? Hmmm you may be on to something there! ;)
 

imported_Snagle

Golden Member
Sep 28, 2004
1,805
0
76

IronWing

No Lifer
Jul 20, 2001
72,903
34,007
136
Originally posted by: DurocShark
Originally posted by: MillionaireNextDoor
A friend's friend in Stanford has such a lens. Cost him $10k to build it with his technique. No one else makes them as far as I know.

Shens

Optics are a well understood science. The only "new" technology was the ability to create aspherical class thanks to computers. But all those really do is correct chromatic aberrations and distortion.

This is probably what he is talking about.

Be sure to check out the movies.

 

DurocShark

Lifer
Apr 18, 2001
15,708
5
56
Originally posted by: ironwing
Originally posted by: DurocShark
Originally posted by: MillionaireNextDoor
A friend's friend in Stanford has such a lens. Cost him $10k to build it with his technique. No one else makes them as far as I know.

Shens

Optics are a well understood science. The only "new" technology was the ability to create aspherical class thanks to computers. But all those really do is correct chromatic aberrations and distortion.

This is probably what he is talking about.

Be sure to check out the movies.
That's still not unlimited DOF. That's multiple lenses capturing multiple images simultaneously.
 

IronWing

No Lifer
Jul 20, 2001
72,903
34,007
136
Originally posted by: DurocShark
Originally posted by: ironwing
Originally posted by: DurocShark
Originally posted by: MillionaireNextDoor
A friend's friend in Stanford has such a lens. Cost him $10k to build it with his technique. No one else makes them as far as I know.

Shens

Optics are a well understood science. The only "new" technology was the ability to create aspherical class thanks to computers. But all those really do is correct chromatic aberrations and distortion.

This is probably what he is talking about.

Be sure to check out the movies.
That's still not unlimited DOF. That's multiple lenses capturing multiple images simultaneously.

Yea, I know, but it seemed to be what MillionaireNextDoor was referring to.
 

Czar

Lifer
Oct 9, 1999
28,510
0
0
Originally posted by: Snagle
Originally posted by: Czar
Originally posted by: Snagle
Originally posted by: DigDug
Yuck. Depth of field is what makes things so interesting. Point and shoots always use infinity focus. That's pictures from those things are so damn boring.


Narrow DoF FTW :) - http://frozensecond.smugmug.com/photos/49456517-L.jpg

Member of the Narrow DOF
http://pics.bbzzdd.com/users/czar/Freyja02.jpg

1.4?
yeah

 

CFster

Golden Member
Oct 16, 1999
1,903
0
76
Your eyes have to refocus - they just do it so fast you don't notice it.

To get everything in focus with a camera you need to close the F-stop to have increased depth of field. The trade off is this cuts the amount of light coming into the camera by half - sometimes more. So either you use a flash (which is only really good for close up to medium distance objects), or you have an SLR with very "fast" and expensive lens.

 

randomlinh

Lifer
Oct 9, 1999
20,846
2
0
linh.wordpress.com
Originally posted by: CFster
Your eyes have to refocus - they just do it so fast you don't notice it.

To get everything in focus with a camera you need to close the F-stop to have increased depth of field. The trade off is this cuts the amount of light coming into the camera by half - sometimes more. So either you use a flash (which is only really good for close up to medium distance objects), or you have an SLR with very "fast" and expensive lens.

er... i've always known a "fast" lens means you can have a huge aperture.. which would be the opposite of what the OP was asking.. no?
 

ShadowBlade

Diamond Member
Feb 11, 2005
4,263
0
0
Originally posted by: mercanucaribe
Originally posted by: C6FT7
Originally posted by: Snagle

Look at the light switch on the wall. Now put your finger in front of your face; is it in focus? Nope.

Umm yes it is - perfectly clear. I'd take a picture but ummm nevermind. :p

That's physically impossible.

qft, just tried it
 

CFster

Golden Member
Oct 16, 1999
1,903
0
76
Originally posted by: randomlinh
Originally posted by: CFster
Your eyes have to refocus - they just do it so fast you don't notice it.

To get everything in focus with a camera you need to close the F-stop to have increased depth of field. The trade off is this cuts the amount of light coming into the camera by half - sometimes more. So either you use a flash (which is only really good for close up to medium distance objects), or you have an SLR with very "fast" and expensive lens.

er... i've always known a "fast" lens means you can have a huge aperture.. which would be the opposite of what the OP was asking.. no?

A fast lens means it lets in a lot of light. Usually they have bigger optics. So, while a one 200mm lens might have a fully open aperature of f4, a more expensive lens might have a aperature of f1.2. BTW, the difference in cost could be in the thousands...

The other benefit to this is they'll let more light in across the whole range. So at f16 (if you choose, for a deep depth of field) you have more available light, enabling you to use a faster shutter speed which eliminates a blurry picture.

Edit: Scratch that. I think I'm wrong about that last part. I think f16 is f16 regardless of the lens - somebody tell me if I'm wrong. The benefit of a faster lens is the maximum aperature available.





 

n yusef

Platinum Member
Feb 20, 2005
2,158
1
0
Originally posted by: CFster
Originally posted by: randomlinh
Originally posted by: CFster
Your eyes have to refocus - they just do it so fast you don't notice it.

To get everything in focus with a camera you need to close the F-stop to have increased depth of field. The trade off is this cuts the amount of light coming into the camera by half - sometimes more. So either you use a flash (which is only really good for close up to medium distance objects), or you have an SLR with very "fast" and expensive lens.

er... i've always known a "fast" lens means you can have a huge aperture.. which would be the opposite of what the OP was asking.. no?

A fast lens means it lets in a lot of light. Usually they have bigger optics. So, while a one 200mm lens might have a fully open aperature of f4, a more expensive lens might have a aperature of f1.2. BTW, the difference in cost could be in the thousands...

The other benefit to this is they'll let more light in across the whole range. So at f16 (if you choose, for a deep depth of field) you have more available light, enabling you to use a faster shutter speed which eliminates a blurry picture.

Edit: Scratch that. I think I'm wrong about that last part. I think f16 is f16 regardless of the lens - somebody tell me if I'm wrong. The benefit of a faster lens is the maximum aperature available.

f16 is f16 is f16. Plus there isn't a 200mm f1.2 lens that I know of. The f-stop of a lens is the ratio of it's focal length to it's aperture size.
 

imported_Condor

Diamond Member
Sep 22, 2004
5,425
0
0
Basically, depth of field is related to how closed the lens is. Fixed F stop lenses are focused from about a foot to infinity because the F stop is pretty high in the realm of F16 - F22. Cheap cameras without manual or auto focus do that. Example: disposable drugstore camera.