Is f/ 1,000,000 a Possible Aperture?

Diffraction limitation and exposure time considerations aside. Can a
photon(s) squeeze through something this tight and still for some kind
of image? And to open it up to, let's say, to f/5000, would one take
ExLax or an aspirin?
Going to the opposite extreme -- can an f/0 "lens" exist (other than in
the imagination or in the Twilight Zone?...
P.S. - What's the bokeh like on an f/1,000,000 (?pinhole?) "lens" and
would you bracket exposures using this "lens" in centuries or light
years? Dark years? Dark Milleniums?

Thebokehking

Re: Is f/ 1,000,000 a Possible Aperture?


Thebokehking

Re: Is f/ 1,000,000 a Possible Aperture?

In article <LC%7h.734$1s6.233@newsread2.news.pas.earthlink.net>,
Nicholas O. Lindan <see@sig.com> writes
Hm, maybe just enlarging lenses then... There are two factors I suppose
tilt it this way: (1) the magnification factor makes diffraction effects
much larger in this application, and (2) enlarger lenses tend to be
optimised for a limited range of conjugates, whereas camera lenses
require to work over a wider range.
Microscope lenses, which of course are designed for use at a fixed
object distance, give maximum resolution wide open. I suspect process
lenses are similar, but these are outside my experience.
David
--
David Littlewood


David Littlewood

Re: Is f/ 1,000,000 a Possible Aperture?

Just looking at a variety of MTF charts (various manufacturers measured
independantly by photodo or Chasseur D'Images) that show peak sharpness
is at anywhere 'tween f/8 to f/16 by lens manuf/FL/speed (and FL for
zooms). Often the curve from f/8 to f/16 (ish) is flat enough as to
really not matter; and for that matter, not significantly sharper than f/8.
--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.


Alan Browne

Re: Is f/ 1,000,000 a Possible Aperture?

"David Littlewood" <david@nospam.demon.co.uk> wrote
That is what I was expecting ... that Summicrons and Micro-Nikkors
would be best at ~4-5.6 and cheaper lenses at F8+. Surprisingly it
was f8 across the board. There was some variation but it was on
the level of noise in the experiment.
Well, perceived sharpness when reading an AF resolution chart
image on a Tech-Pan negative with a research microscope
was the methodology. There was quite a bit of judgement doing it
this way: eye fatigue, the effect of lunch and coffee.
--
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.nolindan.com/da/index.htm
n o lindan at ix dot netcom dot com


Nicholas O. Lindan

Re: Is f/ 1,000,000 a Possible Aperture?

In article <VrG7h.83783$bt1.890736@weber.videotron.net>, Alan Browne
<alan.browne@Freelunchvideotron.ca> writes
Assuming it is not a DoF issue (and I know you are smart enough not to
get confused by this), maximum sharpness at f/16 is not a good advert
for the lens in question. A really outstanding lens for 35mm (which
includes most top enlarging lenses) will give best resolution at f/5.6.
A merely very good or good lens will peak at f/8. For a lens to have a
(necessarily lower) resolution peak at f/16 suggests poorly corrected
aberrations.
Of course, contrast may improve a stop or two down, and this can
sometimes make the perceived sharpness increase on a cursory
examination.
David
--
David Littlewood


David Littlewood

Re: Is f/ 1,000,000 a Possible Aperture?

Strange shot. Thanks for the link, Michael. Deserves to be the cover of
a magazine "Neutrino Daily"? "Arizona Skyways"? "Nippon Muon"? ;-).
When I clicked on the "Super-Kamiokande" Wikipedia link I got...
"Super-K is located 1,000 m underground in Mozumi Mine of the Kamioka
Mining and Smelting Co. in Hida city (formerly Kamioka town), Gifu,
Japan. It consists of 50,000 tons of pure water surrounded by about
11,200 photomultiplier tubes. The cylindrical structure is 41.4 m tall
and 39.3 m across. A neutrino interaction with the electrons or nuclei
of water can produce a particle that moves faster than the speed of
light in water (although of course slower than the speed of light in
vacuum)."
What particle can move faster in light in water (or any other medium
while we're at it) - a tachyon? a chronotron (if such a particle even
exists)? What, and even more important _why_can a particle travel
faster than light? Wouldn't a faster than light particle either a)
violate the laws of physics - "186,282 mps, its not just a good idea,
its the law!" ;-)) or b) travel backwards in time and therefore be
unmeasurable from our forward moving time frame and/or c) be its own
gran' pa'? ;-)
I'm not up on my physics so perhaps somebody who has that bent could
explain it to me...
With faster than light particles could I take a picture before I even
snapped the shutter or just photograph a younger me?... ;-) If I factor
in an f/1,000,000 stop's reciprocity failure with current film using
faster than light particles to make the exposure will I get my 1982
"Test Drive A Leica" Leica back? Will Kodachrome 25 magically reappear
in my camera?


Thebokehking

Re: Is f/ 1,000,000 a Possible Aperture?

Certainly. With some of my 35mm lenses peak measured sharpness is at
about f/16 and others at somewhere between f/8 and f/11.
--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.


Alan Browne

Re: Is f/ 1,000,000 a Possible Aperture?

Then that's why it's tolerated in LF... makes proportionally smaller
blur circle over the whole image.
--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.


Alan Browne

Re: Is f/ 1,000,000 a Possible Aperture?

This depends on how good your lens is and how flat you are holding the
film.
Assuming a good lens, the same film and reasonably flat film you should
see this get bad
at the same f/number regardless of the format.
As you have already noted it does not matter what the FL of the lens
is. So take the case of a 100mm lens in front of 35mm film and 100 mm
lens in front of 4 x 5 film, how is the center 36mm x 24mm piece of
film going to know what format camera it is from? Of course the design
on the 4 x 5 lens is harder because it is much wider angle and so if
the lens is not got aberrations might limit you more then diffraction.
Your f/8 number seems pretty optimist I would be pretty surprised to
see any visible degradation until you were past f/11 and even at f/16
it would take a pretty sharp image to see it , assuming you are using
film.
Scott


Scott W

Re: Is f/ 1,000,000 a Possible Aperture?

The aperture of diminishing returns varies with format. From testing
I have found:
Format Optimum aperture - where closing down
any more makes things visibly worse
35mm f8
6x6 f11
4x5 f22
8x10 f45
Lens focal length didn't seem to have a lot to do with it.
As always, YMMV.
--
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.nolindan.com/da/index.htm
n o lindan at ix dot netcom dot com


Nicholas O. Lindan

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