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Viewing the spokes

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  Viewing the spokes Sergio <invalid@invalid.com> - 2016-08-29 12:08 -0500
    Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-08-29 18:00 +0000
      Re: Viewing the spokes benj <benj@nobody.net> - 2016-08-29 21:00 -0400
        Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-08-30 01:14 +0000
          Re: Viewing the spokes benj <benj@nobody.net> - 2016-08-29 22:45 -0400
            Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-08-30 04:14 +0000
              Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-29 21:59 -0700
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-08-30 05:16 +0000
                  Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-29 23:00 -0700
      Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-08-29 18:29 -0700
    Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-29 18:29 -0700
    Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-29 18:46 -0700
      Re: Viewing the spokes benj <benj@nobody.net> - 2016-08-30 19:40 -0400
        Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-30 22:07 -0700
          Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-30 23:48 -0700
            Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-08-31 09:54 -0700
              Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-09-02 10:00 -0700
                Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-02 13:23 -0700
                Re: Viewing the spokes The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 11:30 -0700
                  Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 13:18 -0700
                    Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 14:57 -0700
                      Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 16:01 -0700
                        Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-04 12:46 -0700
                          Re: Red, Blue and Green Ergios <invalid@invalid.com> - 2016-09-07 12:32 -0500
                            Re: Red, Blue and Green noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-08 12:12 -0700
                          Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-07 23:22 -0700
                    Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 16:03 -0700
                      Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-03 16:06 -0700
                        Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-20 00:18 -0700
                          Re: Red, Blue and Green noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-20 12:52 -0700
                    Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-07 10:01 -0700
                      Re: Red, Blue and Green Gutless Umbrella Carrying Sissy <taustinca@gmail.com> - 2016-09-07 10:12 -0700
                    Re: Red, Blue and Green The Starmaker <starmaker@ix.netcom.com> - 2016-09-20 09:47 -0700
          Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-08-31 14:32 -0700
    Re: Viewing the spokes "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-09-04 11:39 -0700
      Re: Viewing the spokes "hanson" <hanson@quick.net> - 2016-09-04 20:36 -0700
    Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-09 09:08 -0700
      Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-09 12:32 -0700
      Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-09 17:51 -0400
        Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-10 00:10 +0000
          Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-09 20:43 -0400
            Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-10 00:57 +0000
              Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-09 21:07 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-10 01:33 +0000
                  Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-12 20:59 -0400
                    Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-13 02:41 +0000
        Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-09 19:43 -0700
          Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-12 21:29 -0400
            Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-13 02:43 +0000
            Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-13 13:28 -0700
            Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-13 17:14 -0700
              Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-13 21:52 -0400
                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-14 05:11 +0000
                  Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-15 17:49 -0400
                    Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-16 00:50 +0000
                      Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-15 21:52 -0400
                        Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-16 04:11 +0000
                          Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-16 16:58 -0400
                            Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-16 21:40 +0000
                              Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-16 20:56 -0400
                                Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-17 01:47 +0000
                                  Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-17 17:24 -0400
                                    Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-18 00:07 +0000
                Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-14 14:26 -0700
                  Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-14 15:04 -0700
                    Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-16 12:54 -0700
                Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-14 19:47 -0700
                  Re: Viewing the spokes benj <nobody@gmail.com> - 2016-09-14 23:24 -0400
                    Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-15 05:12 +0000
                    Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-15 15:45 -0700
                      Re: Viewing the spokes benj <benj@nobody.net> - 2016-09-15 21:36 -0400
                        Re: Viewing the spokes jimp@specsol.spam.sux.com - 2016-09-16 02:58 +0000
                        Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-18 12:15 -0700
      Re: Viewing the spokes Wally W. <ww84wa@aim.com> - 2016-09-15 09:15 -0400
        Re: Viewing the spokes "nuny@bid.nes" <Alien8752@gmail.com> - 2016-09-15 15:48 -0700
          Re: Viewing the spokes noTthaTguY <abu.kuanysh05@gmail.com> - 2016-09-18 15:33 -0700

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#595068 — Viewing the spokes

Viewing the spokes

A wheel with spokes rolls on the ground. A stationary camera takes a 
picture of the wheel. Due to the nonzero exposure time of the camera, 
the spokes will generally appear blurred. At what location(s) in the 
picture does (do) the spoke(s) not appear
blurred?

























answer,


The contact point on the ground does not look blurred, because it is 
instantaneously
at rest. But although this is the only point on the wheel that is at 
rest, there will
be other locations in the picture where the spokes do not appear blurred.
The relevant property of a point in the picture where a spoke does not 
appear
blurred is that the point lies on the spoke throughout the duration of 
the camera’s
exposure. (The point in the picture need not, however, actually 
correspond to the
same atom on the spoke.)
At a given time, consider a spoke in the lower half of the wheel. A 
short time
later, the spoke will have moved (via both translation and rotation), 
but it will
intersect its original position. The spoke will not appear blurred at 
this intersection
point. We must therefore find the locus of these intersections. We can 
do this in
two ways.
First method: Let R be the radius of the wheel. Consider a spoke that 
makes an
angle of µ with the vertical at a given time. If the wheel then rolls 
through a small
angle dµ, the center moves a distance Rdµ. The spoke’s motion is a 
combination
of a translation through this distance Rdµ, plus a rotation through the 
angle dµ
(around the top end).
Let r be the radial position of the intersection of the initial and 
final positions of
the spoke. In the following figure, we can write down two expressions 
for the short
segment drawn perpendicular to the initial position of the spoke.

Rdq
dq
q
q
r
The two expression are (Rdµ) cos µ, and r dµ (to first order in dµ). 
Equating these
gives r = Rcos µ. This describes a circle whose diameter is the lower 
vertical radius
of the wheel, as shown below.
1
q
r=Rcosq
wheel
Second method: Since the wheel’s contact point with the ground is 
instantaneously
at rest, the wheel may be considered to be instantaneously rotating around
this point. This means that every atom in the wheel (both in the spokes 
and the
rim) instantaneously traces out the arc of a circle centered at the 
contact point. For
the point P in the figure below, this circle is the dotted one drawn 
(with Q being
the contact point). A spoke will not appear blurred at the point where 
this circular
motion is along the direction of the spoke. That is, a spoke will not 
appear blurred
at the point where the dotted circle is tangent to the spoke, as shown.
R
q
P wheel
O
QWe are therefore concerned with the locus of all points P such that the 
segments
PQ and PO are perpendicular. As seen in the previous diagram above, this 
locus
is the circle whose diameter is the lower vertical radius of the wheel.
2

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#595075

Sergio <invalid@invalid.com> wrote:
> Viewing the spokes
> 
> A wheel with spokes rolls on the ground. A stationary camera takes a 
> picture of the wheel. Due to the nonzero exposure time of the camera, 
> the spokes will generally appear blurred. At what location(s) in the 
> picture does (do) the spoke(s) not appear
> blurred?

Depends on the speed of the wheel, the expossure time and the pixel size.

For sufficiently short exposure time and sufficiently slow wheel, nothing
will appear blurred.

For a long enough exposure time and a faster wheel, everything will be
blurred.

In general, if nothing in the image moves more than a a few pixels during
the exposure time, the image will not appear to be blurred to the naked
eye, but would be visible under magnification.

If nothing in the image moves more than about a half pixel during the
exposure time, nothing will be blurred.


-- 
Jim Pennino

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#595166

On 8/29/2016 2:00 PM, jimp@specsol.spam.sux.com wrote:
> Sergio <invalid@invalid.com> wrote:
>> Viewing the spokes
>>
>> A wheel with spokes rolls on the ground. A stationary camera takes a
>> picture of the wheel. Due to the nonzero exposure time of the camera,
>> the spokes will generally appear blurred. At what location(s) in the
>> picture does (do) the spoke(s) not appear
>> blurred?
>
> Depends on the speed of the wheel, the expossure time and the pixel size.
>
> For sufficiently short exposure time and sufficiently slow wheel, nothing
> will appear blurred.
>
> For a long enough exposure time and a faster wheel, everything will be
> blurred.
>
> In general, if nothing in the image moves more than a a few pixels during
> the exposure time, the image will not appear to be blurred to the naked
> eye, but would be visible under magnification.
>
> If nothing in the image moves more than about a half pixel during the
> exposure time, nothing will be blurred.

Usual chimp blather pretending to be 'smart" about science by throwing a 
bunch of jargon around (nobody ever said the images were digital, 
chimpo) to try to impress the rubes here and misses the point Sergio was 
making entirely. The point is that the camera is stationary and where 
the wheel touches the ground is stationary as well, that means that the 
spokes will be less blurry at that will be less blurry than at the top 
of the where. Chimp needs Reber to teach him how to become an "imperial 
thinker".

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#595172

benj <benj@nobody.net> wrote:
> On 8/29/2016 2:00 PM, jimp@specsol.spam.sux.com wrote:
>> Sergio <invalid@invalid.com> wrote:
>>> Viewing the spokes
>>>
>>> A wheel with spokes rolls on the ground. A stationary camera takes a
>>> picture of the wheel. Due to the nonzero exposure time of the camera,
>>> the spokes will generally appear blurred. At what location(s) in the
>>> picture does (do) the spoke(s) not appear
>>> blurred?
>>
>> Depends on the speed of the wheel, the expossure time and the pixel size.
>>
>> For sufficiently short exposure time and sufficiently slow wheel, nothing
>> will appear blurred.
>>
>> For a long enough exposure time and a faster wheel, everything will be
>> blurred.
>>
>> In general, if nothing in the image moves more than a a few pixels during
>> the exposure time, the image will not appear to be blurred to the naked
>> eye, but would be visible under magnification.
>>
>> If nothing in the image moves more than about a half pixel during the
>> exposure time, nothing will be blurred.
> 
> Usual chimp blather pretending to be 'smart" about science by throwing a 
> bunch of jargon around (nobody ever said the images were digital, 
> chimpo)

It doesn't matter if the image is digital or on Kodachrome film.

If the medium is film, you have to determine the pixel size from the
grain size. For prints there is the grain size of the negative and
then the grain size of the print paper and enlargement factor to concider.

That one can do instantaneous calculations of position is irrelevant.

The amount of blurring will be vastly different for an exposure time of
1/1000 of a second versus 10 seconds.


<snip babble>

-- 
Jim Pennino

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#595185

On 8/29/2016 9:14 PM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 8/29/2016 2:00 PM, jimp@specsol.spam.sux.com wrote:
>>> Sergio <invalid@invalid.com> wrote:
>>>> Viewing the spokes
>>>>
>>>> A wheel with spokes rolls on the ground. A stationary camera takes a
>>>> picture of the wheel. Due to the nonzero exposure time of the camera,
>>>> the spokes will generally appear blurred. At what location(s) in the
>>>> picture does (do) the spoke(s) not appear
>>>> blurred?
>>>
>>> Depends on the speed of the wheel, the expossure time and the pixel size.
>>>
>>> For sufficiently short exposure time and sufficiently slow wheel, nothing
>>> will appear blurred.
>>>
>>> For a long enough exposure time and a faster wheel, everything will be
>>> blurred.
>>>
>>> In general, if nothing in the image moves more than a a few pixels during
>>> the exposure time, the image will not appear to be blurred to the naked
>>> eye, but would be visible under magnification.
>>>
>>> If nothing in the image moves more than about a half pixel during the
>>> exposure time, nothing will be blurred.
>>
>> Usual chimp blather pretending to be 'smart" about science by throwing a
>> bunch of jargon around (nobody ever said the images were digital,
>> chimpo)
>
> It doesn't matter if the image is digital or on Kodachrome film.
>
> If the medium is film, you have to determine the pixel size from the
> grain size. For prints there is the grain size of the negative and
> then the grain size of the print paper and enlargement factor to concider.
>
> That one can do instantaneous calculations of position is irrelevant.
>
> The amount of blurring will be vastly different for an exposure time of
> 1/1000 of a second versus 10 seconds.
>
>
> <snip babble>

Senile babble trying to change subject from fact that he missed the 
entire point. Sure just babble on with irrelevant facts and maybe 
someone will be snowed and not notice you totally buggered the question 
and the head kook had to straighten you out.

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#595199

benj <benj@nobody.net> wrote:
> On 8/29/2016 9:14 PM, jimp@specsol.spam.sux.com wrote:
>> benj <benj@nobody.net> wrote:
>>> On 8/29/2016 2:00 PM, jimp@specsol.spam.sux.com wrote:
>>>> Sergio <invalid@invalid.com> wrote:
>>>>> Viewing the spokes
>>>>>
>>>>> A wheel with spokes rolls on the ground. A stationary camera takes a
>>>>> picture of the wheel. Due to the nonzero exposure time of the camera,
>>>>> the spokes will generally appear blurred. At what location(s) in the
>>>>> picture does (do) the spoke(s) not appear
>>>>> blurred?
>>>>
>>>> Depends on the speed of the wheel, the expossure time and the pixel size.
>>>>
>>>> For sufficiently short exposure time and sufficiently slow wheel, nothing
>>>> will appear blurred.
>>>>
>>>> For a long enough exposure time and a faster wheel, everything will be
>>>> blurred.
>>>>
>>>> In general, if nothing in the image moves more than a a few pixels during
>>>> the exposure time, the image will not appear to be blurred to the naked
>>>> eye, but would be visible under magnification.
>>>>
>>>> If nothing in the image moves more than about a half pixel during the
>>>> exposure time, nothing will be blurred.
>>>
>>> Usual chimp blather pretending to be 'smart" about science by throwing a
>>> bunch of jargon around (nobody ever said the images were digital,
>>> chimpo)
>>
>> It doesn't matter if the image is digital or on Kodachrome film.
>>
>> If the medium is film, you have to determine the pixel size from the
>> grain size. For prints there is the grain size of the negative and
>> then the grain size of the print paper and enlargement factor to concider.
>>
>> That one can do instantaneous calculations of position is irrelevant.
>>
>> The amount of blurring will be vastly different for an exposure time of
>> 1/1000 of a second versus 10 seconds.
>>
>>
>> <snip babble>
> 
> Senile babble trying to change subject from fact that he missed the 
> entire point. Sure just babble on with irrelevant facts and maybe 
> someone will be snowed and not notice you totally buggered the question 
> and the head kook had to straighten you out.

If you mean your post where you said where the wheel touches the
ground it is stationary, then your head is clearly up your ass.

It is stationary only instantaneously while the exposure time of any
camera is NOT instantaneous.

If you posit an instantaneous exposure time, then nothing on the
wheel is moving so there is never any blurring.


-- 
Jim Pennino

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#595209

jimp@specsol.spam.sux.com wrote:
> 
> benj <benj@nobody.net> wrote:
> > On 8/29/2016 9:14 PM, jimp@specsol.spam.sux.com wrote:
> >> benj <benj@nobody.net> wrote:
> >>> On 8/29/2016 2:00 PM, jimp@specsol.spam.sux.com wrote:
> >>>> Sergio <invalid@invalid.com> wrote:
> >>>>> Viewing the spokes
> >>>>>
> >>>>> A wheel with spokes rolls on the ground. A stationary camera takes a
> >>>>> picture of the wheel. Due to the nonzero exposure time of the camera,
> >>>>> the spokes will generally appear blurred. At what location(s) in the
> >>>>> picture does (do) the spoke(s) not appear
> >>>>> blurred?
> >>>>
> >>>> Depends on the speed of the wheel, the expossure time and the pixel size.
> >>>>
> >>>> For sufficiently short exposure time and sufficiently slow wheel, nothing
> >>>> will appear blurred.
> >>>>
> >>>> For a long enough exposure time and a faster wheel, everything will be
> >>>> blurred.
> >>>>
> >>>> In general, if nothing in the image moves more than a a few pixels during
> >>>> the exposure time, the image will not appear to be blurred to the naked
> >>>> eye, but would be visible under magnification.
> >>>>
> >>>> If nothing in the image moves more than about a half pixel during the
> >>>> exposure time, nothing will be blurred.
> >>>
> >>> Usual chimp blather pretending to be 'smart" about science by throwing a
> >>> bunch of jargon around (nobody ever said the images were digital,
> >>> chimpo)
> >>
> >> It doesn't matter if the image is digital or on Kodachrome film.
> >>
> >> If the medium is film, you have to determine the pixel size from the
> >> grain size. For prints there is the grain size of the negative and
> >> then the grain size of the print paper and enlargement factor to concider.
> >>
> >> That one can do instantaneous calculations of position is irrelevant.
> >>
> >> The amount of blurring will be vastly different for an exposure time of
> >> 1/1000 of a second versus 10 seconds.
> >>
> >>
> >> <snip babble>
> >
> > Senile babble trying to change subject from fact that he missed the
> > entire point. Sure just babble on with irrelevant facts and maybe
> > someone will be snowed and not notice you totally buggered the question
> > and the head kook had to straighten you out.
> 
> If you mean your post where you said where the wheel touches the
> ground it is stationary, then your head is clearly up your ass.
> 
> It is stationary only instantaneously while the exposure time of any
> camera is NOT instantaneous.
> 
> If you posit an instantaneous exposure time, then nothing on the
> wheel is moving so there is never any blurring.
> 
> --
> Jim Pennino


the spokes atoms on the wheel is always moving...so there is always a blur...never say never.

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#595210

The Starmaker <starmaker@ix.netcom.com> wrote:
> jimp@specsol.spam.sux.com wrote:
>> 
>> benj <benj@nobody.net> wrote:
>> > On 8/29/2016 9:14 PM, jimp@specsol.spam.sux.com wrote:
>> >> benj <benj@nobody.net> wrote:
>> >>> On 8/29/2016 2:00 PM, jimp@specsol.spam.sux.com wrote:
>> >>>> Sergio <invalid@invalid.com> wrote:
>> >>>>> Viewing the spokes
>> >>>>>
>> >>>>> A wheel with spokes rolls on the ground. A stationary camera takes a
>> >>>>> picture of the wheel. Due to the nonzero exposure time of the camera,
>> >>>>> the spokes will generally appear blurred. At what location(s) in the
>> >>>>> picture does (do) the spoke(s) not appear
>> >>>>> blurred?
>> >>>>
>> >>>> Depends on the speed of the wheel, the expossure time and the pixel size.
>> >>>>
>> >>>> For sufficiently short exposure time and sufficiently slow wheel, nothing
>> >>>> will appear blurred.
>> >>>>
>> >>>> For a long enough exposure time and a faster wheel, everything will be
>> >>>> blurred.
>> >>>>
>> >>>> In general, if nothing in the image moves more than a a few pixels during
>> >>>> the exposure time, the image will not appear to be blurred to the naked
>> >>>> eye, but would be visible under magnification.
>> >>>>
>> >>>> If nothing in the image moves more than about a half pixel during the
>> >>>> exposure time, nothing will be blurred.
>> >>>
>> >>> Usual chimp blather pretending to be 'smart" about science by throwing a
>> >>> bunch of jargon around (nobody ever said the images were digital,
>> >>> chimpo)
>> >>
>> >> It doesn't matter if the image is digital or on Kodachrome film.
>> >>
>> >> If the medium is film, you have to determine the pixel size from the
>> >> grain size. For prints there is the grain size of the negative and
>> >> then the grain size of the print paper and enlargement factor to concider.
>> >>
>> >> That one can do instantaneous calculations of position is irrelevant.
>> >>
>> >> The amount of blurring will be vastly different for an exposure time of
>> >> 1/1000 of a second versus 10 seconds.
>> >>
>> >>
>> >> <snip babble>
>> >
>> > Senile babble trying to change subject from fact that he missed the
>> > entire point. Sure just babble on with irrelevant facts and maybe
>> > someone will be snowed and not notice you totally buggered the question
>> > and the head kook had to straighten you out.
>> 
>> If you mean your post where you said where the wheel touches the
>> ground it is stationary, then your head is clearly up your ass.
>> 
>> It is stationary only instantaneously while the exposure time of any
>> camera is NOT instantaneous.
>> 
>> If you posit an instantaneous exposure time, then nothing on the
>> wheel is moving so there is never any blurring.
>> 
>> --
>> Jim Pennino
> 
> 
> the spokes atoms on the wheel is always moving...so there is always a blur...never say never.

I can see the concept of instantaneous is too complex for you.


-- 
Jim Pennino

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#595211

jimp@specsol.spam.sux.com wrote:
> 
> The Starmaker <starmaker@ix.netcom.com> wrote:
> > jimp@specsol.spam.sux.com wrote:
> >>
> >> benj <benj@nobody.net> wrote:
> >> > On 8/29/2016 9:14 PM, jimp@specsol.spam.sux.com wrote:
> >> >> benj <benj@nobody.net> wrote:
> >> >>> On 8/29/2016 2:00 PM, jimp@specsol.spam.sux.com wrote:
> >> >>>> Sergio <invalid@invalid.com> wrote:
> >> >>>>> Viewing the spokes
> >> >>>>>
> >> >>>>> A wheel with spokes rolls on the ground. A stationary camera takes a
> >> >>>>> picture of the wheel. Due to the nonzero exposure time of the camera,
> >> >>>>> the spokes will generally appear blurred. At what location(s) in the
> >> >>>>> picture does (do) the spoke(s) not appear
> >> >>>>> blurred?
> >> >>>>
> >> >>>> Depends on the speed of the wheel, the expossure time and the pixel size.
> >> >>>>
> >> >>>> For sufficiently short exposure time and sufficiently slow wheel, nothing
> >> >>>> will appear blurred.
> >> >>>>
> >> >>>> For a long enough exposure time and a faster wheel, everything will be
> >> >>>> blurred.
> >> >>>>
> >> >>>> In general, if nothing in the image moves more than a a few pixels during
> >> >>>> the exposure time, the image will not appear to be blurred to the naked
> >> >>>> eye, but would be visible under magnification.
> >> >>>>
> >> >>>> If nothing in the image moves more than about a half pixel during the
> >> >>>> exposure time, nothing will be blurred.
> >> >>>
> >> >>> Usual chimp blather pretending to be 'smart" about science by throwing a
> >> >>> bunch of jargon around (nobody ever said the images were digital,
> >> >>> chimpo)
> >> >>
> >> >> It doesn't matter if the image is digital or on Kodachrome film.
> >> >>
> >> >> If the medium is film, you have to determine the pixel size from the
> >> >> grain size. For prints there is the grain size of the negative and
> >> >> then the grain size of the print paper and enlargement factor to concider.
> >> >>
> >> >> That one can do instantaneous calculations of position is irrelevant.
> >> >>
> >> >> The amount of blurring will be vastly different for an exposure time of
> >> >> 1/1000 of a second versus 10 seconds.
> >> >>
> >> >>
> >> >> <snip babble>
> >> >
> >> > Senile babble trying to change subject from fact that he missed the
> >> > entire point. Sure just babble on with irrelevant facts and maybe
> >> > someone will be snowed and not notice you totally buggered the question
> >> > and the head kook had to straighten you out.
> >>
> >> If you mean your post where you said where the wheel touches the
> >> ground it is stationary, then your head is clearly up your ass.
> >>
> >> It is stationary only instantaneously while the exposure time of any
> >> camera is NOT instantaneous.
> >>
> >> If you posit an instantaneous exposure time, then nothing on the
> >> wheel is moving so there is never any blurring.
> >>
> >> --
> >> Jim Pennino
> >
> >
> > the spokes atoms on the wheel is always moving...so there is always a blur...never say never.
> 
> I can see the concept of instantaneous is too complex for you.
> 
> --
> Jim Pennino



i don't have an instamatic camera...

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#595181

what is the minimum number of spokes, say
on the standard 36-spoke bike wheel, and
can it be made symmeterical

> Depends on the speed of the wheel, the expossure time and the pixel size.
> 
> For sufficiently short exposure time and sufficiently slow wheel, nothing
> will appear blurred.
> 
> For a long enough exposure time and a faster wheel, everything will be
> blurred.
> 
> In general, if nothing in the image moves more than a a few pixels during
> the exposure time, the image will not appear to be blurred to the naked
> eye, but would be visible under magnification.
> 
> If nothing in the image moves more than about a half pixel during the
> exposure time, nothing will be blurred.
> 
> 
> -- 
> Jim Pennino

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#595180

Sergio wrote:
> 
> Viewing the spokes
> 
> A wheel with spokes rolls on the ground. A stationary camera takes a
> picture of the wheel. Due to the nonzero exposure time of the camera,
> the spokes will generally appear blurred. At what location(s) in the
> picture does (do) the spoke(s) not appear
> blurred?
> 
> answer,
 
 The contact point on the ground does not look blurred, because it is
 instantaneously
 at rest. But although this is the only point on the wheel that is at
 rest, there will
 be other locations in the picture where the spokes do not appear blurred.
 The relevant property of a point in the picture where a spoke does not
 appear
 blurred is that the point lies on the spoke throughout the duration of
 the camera’s
 exposure. (The point in the picture need not, however, actually
 correspond to the
 same atom on the spoke.)
 At a given time, consider a spoke in the lower half of the wheel. A
 short time
 later, the spoke will have moved (via both translation and rotation),
 but it will
 intersect its original position. The spoke will not appear blurred at
 this intersection
 point. We must therefore find the locus of these intersections. We can
 do this in
 two ways.
 First method: Let R be the radius of the wheel. Consider a spoke that
 makes an
 angle of µ with the vertical at a given time. If the wheel then rolls
 through a small
 angle dµ, the center moves a distance Rdµ. The spoke’s motion is a
 combination
 of a translation through this distance Rdµ, plus a rotation through the
 angle dµ
 (around the top end).
 Let r be the radial position of the intersection of the initial and
 final positions of
 the spoke. In the following figure, we can write down two expressions
 for the short
 segment drawn perpendicular to the initial position of the spoke.
 
 Rdq
 dq
 q
 q
 r
 The two expression are (Rdµ) cos µ, and r dµ (to first order in dµ).
 Equating these
 gives r = Rcos µ. This describes a circle whose diameter is the lower
 vertical radius
 of the wheel, as shown below.
 1
 q
 r=Rcosq
 wheel
 Second method: Since the wheel’s contact point with the ground is
 instantaneously
 at rest, the wheel may be considered to be instantaneously rotating around
 this point. This means that every atom in the wheel (both in the spokes
 and the
 rim) instantaneously traces out the arc of a circle centered at the
 contact point. For
 the point P in the figure below, this circle is the dotted one drawn
 (with Q being
 the contact point). A spoke will not appear blurred at the point where
 this circular
 motion is along the direction of the spoke. That is, a spoke will not
 appear blurred
 at the point where the dotted circle is tangent to the spoke, as shown.
 R
 q
 P wheel
 O
 QWe are therefore concerned with the locus of all points P such that the
 segments
 PQ and PO are perpendicular. As seen in the previous diagram above, this
 locus
 is the circle whose diameter is the lower vertical radius of the wheel.
 2

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#595183

i have a question for you...

why are there two primary colors on earth?

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#595294

On 8/29/2016 9:46 PM, The Starmaker wrote:
> i have a question for you...
>
> why are there two primary colors on earth?
>
That is so everything in your life can look like shit.

I presume you are too young to have ever seen what the old two color 
technicolor movies used to look like.

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#595313

benj wrote:
> 
> On 8/29/2016 9:46 PM, The Starmaker wrote:
> > i have a question for you...
> >
> > why are there two primary colors on earth?
> >
> That is so everything in your life can look like shit.
> 
> I presume you are too young to have ever seen what the old two color
> technicolor movies used to look like.


The Two Primary Colors are:

1) Blue, Red, Green

2) Blue, Red, Yellow



why are there Two primary colors on earth?

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#595314

The Starmaker wrote:
> 
> benj wrote:
> >
> > On 8/29/2016 9:46 PM, The Starmaker wrote:
> > > i have a question for you...
> > >
> > > why are there two primary colors on earth?
> > >
> > That is so everything in your life can look like shit.
> >
> > I presume you are too young to have ever seen what the old two color
> > technicolor movies used to look like.
> 
> The Two Primary Colors are:
> 
> 1) Blue, Red, Green
> 
> 2) Blue, Red, Yellow
> 
> why are there Two primary colors on earth?

I might have to define the word Primary because it's a pattern with yous people not
knowing or understanding the english language....especially in the united states scientific community.


http://www.dictionary.com/browse/primary

1.
first or highest in rank or importance; chief; principal: 
(his primary goals in life.)

Not, his primaries goals in like, "primary"...meaning One.

 2.
first in order in any series, sequence, etc.


 5.
constituting or belonging to the first stage in any process.


Now, if you look at the definition of the words:
http://www.dictionary.com/browse/primary-color

 1.
Art. a color, as red, yellow, or blue, that in mixture yields other colors.
Compare complementary color (def 1), secondary color, tertiary color.
2.
Optics. any of a set of monochromatic colors, as red, green, and blue, that are added to match or specify the chromaticity of a stimulus or sample.


There above are Two primary colors

1.red, yellow, and blue

2.red, green, and blue


Both by definition are:

1) primary-colors

2) They are both "first"

3)They are both "the first stage", first in order in any series...


There are both First primary colors.


My question is...why are there two "primary" colors on earth?

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#595336

The Starmaker wrote:
> 
> The Starmaker wrote:
> >
> > benj wrote:
> > >
> > > On 8/29/2016 9:46 PM, The Starmaker wrote:
> > > > i have a question for you...
> > > >
> > > > why are there two primary colors on earth?
> > > >
> > > That is so everything in your life can look like shit.
> > >
> > > I presume you are too young to have ever seen what the old two color
> > > technicolor movies used to look like.
> >
> > The Two Primary Colors are:
> >
> > 1) Blue, Red, Green
> >
> > 2) Blue, Red, Yellow
> >
> > why are there Two primary colors on earth?
> 
> I might have to define the word Primary because it's a pattern with yous people not
> knowing or understanding the english language....especially in the united states scientific community.
> 
> http://www.dictionary.com/browse/primary
> 
> 1.
> first or highest in rank or importance; chief; principal:
> (his primary goals in life.)
> 
> Not, his primaries goals in like, "primary"...meaning One.
> 
>  2.
> first in order in any series, sequence, etc.
> 
>  5.
> constituting or belonging to the first stage in any process.
> 
> Now, if you look at the definition of the words:
> http://www.dictionary.com/browse/primary-color
> 
>  1.
> Art. a color, as red, yellow, or blue, that in mixture yields other colors.
> Compare complementary color (def 1), secondary color, tertiary color.
> 2.
> Optics. any of a set of monochromatic colors, as red, green, and blue, that are added to match or specify the chromaticity of a stimulus or sample.
> 
> There above are Two primary colors
> 
> 1.red, yellow, and blue
> 
> 2.red, green, and blue
> 
> Both by definition are:
> 
> 1) primary-colors
> 
> 2) They are both "first"
> 
> 3)They are both "the first stage", first in order in any series...
> 
> There are both First primary colors.
> 
> My question is...why are there two "primary" colors on earth?


Now, if you have a problem with the word "Why", I can change it to
"How".



How are there two "primary" colors on earth?

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#595620

The Starmaker wrote:
> 
> The Starmaker wrote:
> >
> > The Starmaker wrote:
> > >
> > > benj wrote:
> > > >
> > > > On 8/29/2016 9:46 PM, The Starmaker wrote:
> > > > > i have a question for you...
> > > > >
> > > > > why are there two primary colors on earth?
> > > > >
> > > > That is so everything in your life can look like shit.
> > > >
> > > > I presume you are too young to have ever seen what the old two color
> > > > technicolor movies used to look like.
> > >
> > > The Two Primary Colors are:
> > >
> > > 1) Blue, Red, Green
> > >
> > > 2) Blue, Red, Yellow
> > >
> > > why are there Two primary colors on earth?
> >
> > I might have to define the word Primary because it's a pattern with yous people not
> > knowing or understanding the english language....especially in the united states scientific community.
> >
> > http://www.dictionary.com/browse/primary
> >
> > 1.
> > first or highest in rank or importance; chief; principal:
> > (his primary goals in life.)
> >
> > Not, his primaries goals in like, "primary"...meaning One.
> >
> >  2.
> > first in order in any series, sequence, etc.
> >
> >  5.
> > constituting or belonging to the first stage in any process.
> >
> > Now, if you look at the definition of the words:
> > http://www.dictionary.com/browse/primary-color
> >
> >  1.
> > Art. a color, as red, yellow, or blue, that in mixture yields other colors.
> > Compare complementary color (def 1), secondary color, tertiary color.
> > 2.
> > Optics. any of a set of monochromatic colors, as red, green, and blue, that are added to match or specify the chromaticity of a stimulus or sample.
> >
> > There above are Two primary colors
> >
> > 1.red, yellow, and blue
> >
> > 2.red, green, and blue
> >
> > Both by definition are:
> >
> > 1) primary-colors
> >
> > 2) They are both "first"
> >
> > 3)They are both "the first stage", first in order in any series...
> >
> > There are both First primary colors.
> >
> > My question is...why are there two "primary" colors on earth?
> 
> Now, if you have a problem with the word "Why", I can change it to
> "How".
> 
> How are there two "primary" colors on earth?


Of course...I'm the only one on earth that can answer this physics question correctly..

It's a mistake!

When the primarys colors red, blue and green first came into being, ...and around
4.5 billion years later the earth was formed..making the primary colors
red, blue and green for pigments didn't work! So, it had to be changed/added
 (a new set of primary colors) from Green to Yellow.

And that fixed the mistake.


Whether the mistake was created by Nature error, or a computer error..regardless...it was corrected.

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#595642

just crap;
ye olde primaries were from painting,
til Ed lanD dyscovered the apparent trichromacy, but
there are no r, g & b pixels in the retina, and
no associated pigments (other than the one for far-red

>  (a new set of primary colors) from Green to Yellow.
> 
> And that fixed the mistake.
> 
> 
> Whether the mistake was created by Nature error, or a computer error..regardless...it was corrected.

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#595706

The Starmaker wrote:
> 
> The Starmaker wrote:
> >
> > The Starmaker wrote:
> > >
> > > The Starmaker wrote:
> > > >
> > > > benj wrote:
> > > > >
> > > > > On 8/29/2016 9:46 PM, The Starmaker wrote:
> > > > > > i have a question for you...
> > > > > >
> > > > > > why are there two primary colors on earth?
> > > > > >
> > > > > That is so everything in your life can look like shit.
> > > > >
> > > > > I presume you are too young to have ever seen what the old two color
> > > > > technicolor movies used to look like.
> > > >
> > > > The Two Primary Colors are:
> > > >
> > > > 1) Blue, Red, Green
> > > >
> > > > 2) Blue, Red, Yellow
> > > >
> > > > why are there Two primary colors on earth?
> > >
> > > I might have to define the word Primary because it's a pattern with yous people not
> > > knowing or understanding the english language....especially in the united states scientific community.
> > >
> > > http://www.dictionary.com/browse/primary
> > >
> > > 1.
> > > first or highest in rank or importance; chief; principal:
> > > (his primary goals in life.)
> > >
> > > Not, his primaries goals in like, "primary"...meaning One.
> > >
> > >  2.
> > > first in order in any series, sequence, etc.
> > >
> > >  5.
> > > constituting or belonging to the first stage in any process.
> > >
> > > Now, if you look at the definition of the words:
> > > http://www.dictionary.com/browse/primary-color
> > >
> > >  1.
> > > Art. a color, as red, yellow, or blue, that in mixture yields other colors.
> > > Compare complementary color (def 1), secondary color, tertiary color.
> > > 2.
> > > Optics. any of a set of monochromatic colors, as red, green, and blue, that are added to match or specify the chromaticity of a stimulus or sample.
> > >
> > > There above are Two primary colors
> > >
> > > 1.red, yellow, and blue
> > >
> > > 2.red, green, and blue
> > >
> > > Both by definition are:
> > >
> > > 1) primary-colors
> > >
> > > 2) They are both "first"
> > >
> > > 3)They are both "the first stage", first in order in any series...
> > >
> > > There are both First primary colors.
> > >
> > > My question is...why are there two "primary" colors on earth?
> >
> > Now, if you have a problem with the word "Why", I can change it to
> > "How".
> >
> > How are there two "primary" colors on earth?
> 
> Of course...I'm the only one on earth that can answer this physics question correctly..
> 
> It's a mistake!
> 
> When the primarys colors red, blue and green first came into being, ...and around
> 4.5 billion years later the earth was formed..making the primary colors
> red, blue and green for pigments didn't work! So, it had to be changed/added
>  (a new set of primary colors) from Green to Yellow.
> 
> And that fixed the mistake.
> 
> Whether the mistake was created by Nature error, or a computer error..regardless...it was corrected.

Now, can you imagine what it would be like if there was only one set of primary colors, red, blue and green in the entire universe?

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#595712 — Red, Blue and Green

The Starmaker wrote:
> 
> The Starmaker wrote:
> >
> > The Starmaker wrote:
> > >
> > > The Starmaker wrote:
> > > >
> > > > The Starmaker wrote:
> > > > >
> > > > > benj wrote:
> > > > > >
> > > > > > On 8/29/2016 9:46 PM, The Starmaker wrote:
> > > > > > > i have a question for you...
> > > > > > >
> > > > > > > why are there two primary colors on earth?
> > > > > > >
> > > > > > That is so everything in your life can look like shit.
> > > > > >
> > > > > > I presume you are too young to have ever seen what the old two color
> > > > > > technicolor movies used to look like.
> > > > >
> > > > > The Two Primary Colors are:
> > > > >
> > > > > 1) Blue, Red, Green
> > > > >
> > > > > 2) Blue, Red, Yellow
> > > > >
> > > > > why are there Two primary colors on earth?
> > > >
> > > > I might have to define the word Primary because it's a pattern with yous people not
> > > > knowing or understanding the english language....especially in the united states scientific community.
> > > >
> > > > http://www.dictionary.com/browse/primary
> > > >
> > > > 1.
> > > > first or highest in rank or importance; chief; principal:
> > > > (his primary goals in life.)
> > > >
> > > > Not, his primaries goals in like, "primary"...meaning One.
> > > >
> > > >  2.
> > > > first in order in any series, sequence, etc.
> > > >
> > > >  5.
> > > > constituting or belonging to the first stage in any process.
> > > >
> > > > Now, if you look at the definition of the words:
> > > > http://www.dictionary.com/browse/primary-color
> > > >
> > > >  1.
> > > > Art. a color, as red, yellow, or blue, that in mixture yields other colors.
> > > > Compare complementary color (def 1), secondary color, tertiary color.
> > > > 2.
> > > > Optics. any of a set of monochromatic colors, as red, green, and blue, that are added to match or specify the chromaticity of a stimulus or sample.
> > > >
> > > > There above are Two primary colors
> > > >
> > > > 1.red, yellow, and blue
> > > >
> > > > 2.red, green, and blue
> > > >
> > > > Both by definition are:
> > > >
> > > > 1) primary-colors
> > > >
> > > > 2) They are both "first"
> > > >
> > > > 3)They are both "the first stage", first in order in any series...
> > > >
> > > > There are both First primary colors.
> > > >
> > > > My question is...why are there two "primary" colors on earth?
> > >
> > > Now, if you have a problem with the word "Why", I can change it to
> > > "How".
> > >
> > > How are there two "primary" colors on earth?
> >
> > Of course...I'm the only one on earth that can answer this physics question correctly..
> >
> > It's a mistake!
> >
> > When the primarys colors red, blue and green first came into being, ...and around
> > 4.5 billion years later the earth was formed..making the primary colors
> > red, blue and green for pigments didn't work! So, it had to be changed/added
> >  (a new set of primary colors) from Green to Yellow.
> >
> > And that fixed the mistake.
> >
> > Whether the mistake was created by Nature error, or a computer error..regardless...it was corrected.
> 
> Now, can you imagine what it would be like if there was only one set of primary colors, red, blue and green in the entire universe?


If you try and paint a picture, using Red, Blue and Green (which mixed will be White) and you add Red to make pink...you'll get White instead!

If you buy a jar of White paint, (Red, Blue and Green mixed) and you add Blue...you get White.

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