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Groups > sci.physics > #595068 > unrolled thread

Viewing the spokes

Started bySergio <invalid@invalid.com>
First post2016-08-29 12:08 -0500
Last post2016-09-18 15:33 -0700
Articles 20 on this page of 76 — 12 participants

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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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#596444

Frombenj <benj@nobody.net>
Date2016-09-09 20:43 -0400
Message-ID<57d35734$0$31237$c3e8da3$dd9697d2@news.astraweb.com>
In reply to#596434
On 9/9/2016 8:10 PM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>
>>>   There is no "instantaneous". The wheel *moves* while the shutter is open, hence the contact patch will move, hence the lowermost spokes will be blurred.
>>>
>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>
>>>
>>>   Mark L. Fergerson
>>>
>> Actually, Mark, only the point of the wheel touching the ground which
>> would be the rim is at rest. And even then that "point' will be
>> rotating. But as we all know from the establishment science everyone
>> here believes in, the rotation of a point particle will not produce any
>> blurring in the camera image. OF course that "point particle" is NOT
>> located on a spoke so for that reason your answer stands as correct.
>
> A point is a mathematical construct and has nothing to do with cameras
> in the real world.
>
> During the time the shutter is open, EVERYTHING on the wheel is moving
> some amount both in rotation and linearly.
>
> How blurred anything is depends on the rotational and linear speed of
> the wheel relative to the view of the camera, the exposure time and the
> resolution of the camera.

We are all well aware of this jim. However the point touching the ground 
does not move linearly as I've already noted. Hence you should have said 
"rotation OR linearly" rather than "rotation and linearly".

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#596452

Fromjimp@specsol.spam.sux.com
Date2016-09-10 00:57 +0000
Message-ID<mc2cad-772.ln1@mail.specsol.com>
In reply to#596444
benj <benj@nobody.net> wrote:
> On 9/9/2016 8:10 PM, jimp@specsol.spam.sux.com wrote:
>> benj <benj@nobody.net> wrote:
>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>
>>>>   There is no "instantaneous". The wheel *moves* while the shutter is open, hence the contact patch will move, hence the lowermost spokes will be blurred.
>>>>
>>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>>
>>>>
>>>>   Mark L. Fergerson
>>>>
>>> Actually, Mark, only the point of the wheel touching the ground which
>>> would be the rim is at rest. And even then that "point' will be
>>> rotating. But as we all know from the establishment science everyone
>>> here believes in, the rotation of a point particle will not produce any
>>> blurring in the camera image. OF course that "point particle" is NOT
>>> located on a spoke so for that reason your answer stands as correct.
>>
>> A point is a mathematical construct and has nothing to do with cameras
>> in the real world.
>>
>> During the time the shutter is open, EVERYTHING on the wheel is moving
>> some amount both in rotation and linearly.
>>
>> How blurred anything is depends on the rotational and linear speed of
>> the wheel relative to the view of the camera, the exposure time and the
>> resolution of the camera.
> 
> We are all well aware of this jim. However the point touching the ground 
> does not move linearly as I've already noted. Hence you should have said 
> "rotation OR linearly" rather than "rotation and linearly".
 
Set the camera exposure time to 1 hour.

How far does the point touching the ground move in 1 hour?
 

-- 
Jim Pennino

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#596454

Frombenj <benj@nobody.net>
Date2016-09-09 21:07 -0400
Message-ID<57d35ced$0$62038$b1db1813$2411a48f@news.astraweb.com>
In reply to#596452
On 9/9/2016 8:57 PM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 9/9/2016 8:10 PM, jimp@specsol.spam.sux.com wrote:
>>> benj <benj@nobody.net> wrote:
>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>
>>>>>   There is no "instantaneous". The wheel *moves* while the shutter is open, hence the contact patch will move, hence the lowermost spokes will be blurred.
>>>>>
>>>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>>>
>>>>>
>>>>>   Mark L. Fergerson
>>>>>
>>>> Actually, Mark, only the point of the wheel touching the ground which
>>>> would be the rim is at rest. And even then that "point' will be
>>>> rotating. But as we all know from the establishment science everyone
>>>> here believes in, the rotation of a point particle will not produce any
>>>> blurring in the camera image. OF course that "point particle" is NOT
>>>> located on a spoke so for that reason your answer stands as correct.
>>>
>>> A point is a mathematical construct and has nothing to do with cameras
>>> in the real world.
>>>
>>> During the time the shutter is open, EVERYTHING on the wheel is moving
>>> some amount both in rotation and linearly.
>>>
>>> How blurred anything is depends on the rotational and linear speed of
>>> the wheel relative to the view of the camera, the exposure time and the
>>> resolution of the camera.
>>
>> We are all well aware of this jim. However the point touching the ground
>> does not move linearly as I've already noted. Hence you should have said
>> "rotation OR linearly" rather than "rotation and linearly".
>
> Set the camera exposure time to 1 hour.
>
> How far does the point touching the ground move in 1 hour?

Doesn't move at all because if the same point is touching the ground for 
an hour then the wheel isn't turning very fast. In fact I say the wheel 
is turning extremely slowly. There goes your logic out the window.

(We all observe that the angular velocity of the wheel has not been 
specified, right? Right.)

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#596457

Fromjimp@specsol.spam.sux.com
Date2016-09-10 01:33 +0000
Message-ID<uf4cad-fc2.ln1@mail.specsol.com>
In reply to#596454
benj <benj@nobody.net> wrote:
> On 9/9/2016 8:57 PM, jimp@specsol.spam.sux.com wrote:
>> benj <benj@nobody.net> wrote:
>>> On 9/9/2016 8:10 PM, jimp@specsol.spam.sux.com wrote:
>>>> benj <benj@nobody.net> wrote:
>>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>>
>>>>>>   There is no "instantaneous". The wheel *moves* while the shutter is open, hence the contact patch will move, hence the lowermost spokes will be blurred.
>>>>>>
>>>>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>>>>
>>>>>>
>>>>>>   Mark L. Fergerson
>>>>>>
>>>>> Actually, Mark, only the point of the wheel touching the ground which
>>>>> would be the rim is at rest. And even then that "point' will be
>>>>> rotating. But as we all know from the establishment science everyone
>>>>> here believes in, the rotation of a point particle will not produce any
>>>>> blurring in the camera image. OF course that "point particle" is NOT
>>>>> located on a spoke so for that reason your answer stands as correct.
>>>>
>>>> A point is a mathematical construct and has nothing to do with cameras
>>>> in the real world.
>>>>
>>>> During the time the shutter is open, EVERYTHING on the wheel is moving
>>>> some amount both in rotation and linearly.
>>>>
>>>> How blurred anything is depends on the rotational and linear speed of
>>>> the wheel relative to the view of the camera, the exposure time and the
>>>> resolution of the camera.
>>>
>>> We are all well aware of this jim. However the point touching the ground
>>> does not move linearly as I've already noted. Hence you should have said
>>> "rotation OR linearly" rather than "rotation and linearly".
>>
>> Set the camera exposure time to 1 hour.
>>
>> How far does the point touching the ground move in 1 hour?
> 
> Doesn't move at all because if the same point is touching the ground for 
> an hour then the wheel isn't turning very fast. In fact I say the wheel 
> is turning extremely slowly. There goes your logic out the window.

I did not say the same point was touching the ground for an hour.

What I did say was that the problem depends on the rotational and linear
speed of the wheel relative to the view of the camera.

> (We all observe that the angular velocity of the wheel has not been 
> specified, right? Right.)

OK, the angular velocity of the wheel is such that it's linear velocity
over the ground is equal to the field of view of the camera in 1 hour
and the shutter is opened when the bottom of the wheel is at the edge
of the field of view.

Exposure time is still 1 hour.

The point touching the ground appears as a steak that is the sum of the
exposure of the point touching the ground AND the background, whatever
it is.


-- 
Jim Pennino

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#596730

Frombenj <benj@nobody.net>
Date2016-09-12 20:59 -0400
Message-ID<57d74f6f$0$62143$b1db1813$2411a48f@news.astraweb.com>
In reply to#596457
On 9/9/2016 9:33 PM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 9/9/2016 8:57 PM, jimp@specsol.spam.sux.com wrote:
>>> benj <benj@nobody.net> wrote:
>>>> On 9/9/2016 8:10 PM, jimp@specsol.spam.sux.com wrote:
>>>>> benj <benj@nobody.net> wrote:
>>>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>>>
>>>>>>>   There is no "instantaneous". The wheel *moves* while the shutter is open, hence the contact patch will move, hence the lowermost spokes will be blurred.
>>>>>>>
>>>>>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>>>>>
>>>>>>>
>>>>>>>   Mark L. Fergerson
>>>>>>>
>>>>>> Actually, Mark, only the point of the wheel touching the ground which
>>>>>> would be the rim is at rest. And even then that "point' will be
>>>>>> rotating. But as we all know from the establishment science everyone
>>>>>> here believes in, the rotation of a point particle will not produce any
>>>>>> blurring in the camera image. OF course that "point particle" is NOT
>>>>>> located on a spoke so for that reason your answer stands as correct.
>>>>>
>>>>> A point is a mathematical construct and has nothing to do with cameras
>>>>> in the real world.
>>>>>
>>>>> During the time the shutter is open, EVERYTHING on the wheel is moving
>>>>> some amount both in rotation and linearly.
>>>>>
>>>>> How blurred anything is depends on the rotational and linear speed of
>>>>> the wheel relative to the view of the camera, the exposure time and the
>>>>> resolution of the camera.
>>>>
>>>> We are all well aware of this jim. However the point touching the ground
>>>> does not move linearly as I've already noted. Hence you should have said
>>>> "rotation OR linearly" rather than "rotation and linearly".
>>>
>>> Set the camera exposure time to 1 hour.
>>>
>>> How far does the point touching the ground move in 1 hour?
>>
>> Doesn't move at all because if the same point is touching the ground for
>> an hour then the wheel isn't turning very fast. In fact I say the wheel
>> is turning extremely slowly. There goes your logic out the window.
>
> I did not say the same point was touching the ground for an hour.
>
> What I did say was that the problem depends on the rotational and linear
> speed of the wheel relative to the view of the camera.
>
>> (We all observe that the angular velocity of the wheel has not been
>> specified, right? Right.)
>
> OK, the angular velocity of the wheel is such that it's linear velocity
> over the ground is equal to the field of view of the camera in 1 hour
> and the shutter is opened when the bottom of the wheel is at the edge
> of the field of view.
>
> Exposure time is still 1 hour.
>
> The point touching the ground appears as a steak that is the sum of the
> exposure of the point touching the ground AND the background, whatever
> it is.

Well, that defines things better! But interestingly enough, you must 
agree that the GROUND will be in focus (It's not moving at all) and 
while no "spoke" will be in focus as Sergio asked, it would appear that 
the points on the very rim of the wheel may "sort of" be in focus as 
they drop down to the ground, stay there for period of time and then 
lift up. This is a lot like a scheme I invented to give depth of field 
to microscope images. You crank through focus and the sharp parts of the 
image register while the blurry parts just smear out and overlap and are 
lost.

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#596756

Fromjimp@specsol.spam.sux.com
Date2016-09-13 02:41 +0000
Message-ID<8k5kad-rjs.ln1@mail.specsol.com>
In reply to#596730
benj <benj@nobody.net> wrote:
> On 9/9/2016 9:33 PM, jimp@specsol.spam.sux.com wrote:
>> benj <benj@nobody.net> wrote:
>>> On 9/9/2016 8:57 PM, jimp@specsol.spam.sux.com wrote:
>>>> benj <benj@nobody.net> wrote:
>>>>> On 9/9/2016 8:10 PM, jimp@specsol.spam.sux.com wrote:
>>>>>> benj <benj@nobody.net> wrote:
>>>>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>>>>
>>>>>>>>   There is no "instantaneous". The wheel *moves* while the shutter is open, hence the contact patch will move, hence the lowermost spokes will be blurred.
>>>>>>>>
>>>>>>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>>>>>>
>>>>>>>>
>>>>>>>>   Mark L. Fergerson
>>>>>>>>
>>>>>>> Actually, Mark, only the point of the wheel touching the ground which
>>>>>>> would be the rim is at rest. And even then that "point' will be
>>>>>>> rotating. But as we all know from the establishment science everyone
>>>>>>> here believes in, the rotation of a point particle will not produce any
>>>>>>> blurring in the camera image. OF course that "point particle" is NOT
>>>>>>> located on a spoke so for that reason your answer stands as correct.
>>>>>>
>>>>>> A point is a mathematical construct and has nothing to do with cameras
>>>>>> in the real world.
>>>>>>
>>>>>> During the time the shutter is open, EVERYTHING on the wheel is moving
>>>>>> some amount both in rotation and linearly.
>>>>>>
>>>>>> How blurred anything is depends on the rotational and linear speed of
>>>>>> the wheel relative to the view of the camera, the exposure time and the
>>>>>> resolution of the camera.
>>>>>
>>>>> We are all well aware of this jim. However the point touching the ground
>>>>> does not move linearly as I've already noted. Hence you should have said
>>>>> "rotation OR linearly" rather than "rotation and linearly".
>>>>
>>>> Set the camera exposure time to 1 hour.
>>>>
>>>> How far does the point touching the ground move in 1 hour?
>>>
>>> Doesn't move at all because if the same point is touching the ground for
>>> an hour then the wheel isn't turning very fast. In fact I say the wheel
>>> is turning extremely slowly. There goes your logic out the window.
>>
>> I did not say the same point was touching the ground for an hour.
>>
>> What I did say was that the problem depends on the rotational and linear
>> speed of the wheel relative to the view of the camera.
>>
>>> (We all observe that the angular velocity of the wheel has not been
>>> specified, right? Right.)
>>
>> OK, the angular velocity of the wheel is such that it's linear velocity
>> over the ground is equal to the field of view of the camera in 1 hour
>> and the shutter is opened when the bottom of the wheel is at the edge
>> of the field of view.
>>
>> Exposure time is still 1 hour.
>>
>> The point touching the ground appears as a steak that is the sum of the
>> exposure of the point touching the ground AND the background, whatever
>> it is.
> 
> Well, that defines things better! But interestingly enough, you must 
> agree that the GROUND will be in focus (It's not moving at all) and 
> while no "spoke" will be in focus as Sergio asked, it would appear that 
> the points on the very rim of the wheel may "sort of" be in focus as 
> they drop down to the ground, stay there for period of time and then 
> lift up. This is a lot like a scheme I invented to give depth of field 
> to microscope images. You crank through focus and the sharp parts of the 
> image register while the blurry parts just smear out and overlap and are 
> lost.

No one said anything about focus and focus is an entirely different
subject and effect than bluring due to movement.
 

-- 
Jim Pennino

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#596465

From"nuny@bid.nes" <Alien8752@gmail.com>
Date2016-09-09 19:43 -0700
Message-ID<d2651d9e-7980-4fee-8a9c-e1f58743603f@googlegroups.com>
In reply to#596404
On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
> > On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
> >
> >   There is no "instantaneous". The wheel *moves* while the shutter is open,
> > hence the contact patch will move, hence the lowermost spokes will be
> > blurred.
> >
> >   Now, if you want to talk about which spokes will be *least* blurred...
> >
> Actually, Mark, only the point of the wheel touching the ground which 
> would be the rim is at rest.

  Actually, no, because the shutter can't open *and close* "instantaneously".

  The contact patch *moves* while the shutter is open.


  Mark L. Fergerson

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#596736

Frombenj <benj@nobody.net>
Date2016-09-12 21:29 -0400
Message-ID<57d7567e$0$62107$b1db1813$2411a48f@news.astraweb.com>
In reply to#596465
On 9/9/2016 10:43 PM, nuny@bid.nes wrote:
> On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>
>>>   There is no "instantaneous". The wheel *moves* while the shutter is open,
>>> hence the contact patch will move, hence the lowermost spokes will be
>>> blurred.
>>>
>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>
>> Actually, Mark, only the point of the wheel touching the ground which
>> would be the rim is at rest.
>
>   Actually, no, because the shutter can't open *and close* "instantaneously".
>
>   The contact patch *moves* while the shutter is open.
>
>
>   Mark L. Fergerson
>
No it does not. The points on the ground actually rise from the ground 
before moving on so all the contact points are stationary. And that 
means they are in focus while the shutter is open. So what you have is a 
LINE of stationary in focus contact points. No?

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#596757

Fromjimp@specsol.spam.sux.com
Date2016-09-13 02:43 +0000
Message-ID<9n5kad-rjs.ln1@mail.specsol.com>
In reply to#596736
benj <benj@nobody.net> wrote:
> On 9/9/2016 10:43 PM, nuny@bid.nes wrote:
>> On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>
>>>>   There is no "instantaneous". The wheel *moves* while the shutter is open,
>>>> hence the contact patch will move, hence the lowermost spokes will be
>>>> blurred.
>>>>
>>>>   Now, if you want to talk about which spokes will be *least* blurred...
>>>>
>>> Actually, Mark, only the point of the wheel touching the ground which
>>> would be the rim is at rest.
>>
>>   Actually, no, because the shutter can't open *and close* "instantaneously".
>>
>>   The contact patch *moves* while the shutter is open.
>>
>>
>>   Mark L. Fergerson
>>
> No it does not. The points on the ground actually rise from the ground 
> before moving on so all the contact points are stationary. And that 
> means they are in focus while the shutter is open. So what you have is a 
> LINE of stationary in focus contact points. No?

No, you have a blurred line of multiple exposed background and contact
points.

Bluring due to motion has nothing to do with focus.


-- 
Jim Pennino

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#596840

FromnoTthaTguY <abu.kuanysh05@gmail.com>
Date2016-09-13 13:28 -0700
Message-ID<befd1662-84d7-4325-be6f-7421c25e9c7e@googlegroups.com>
In reply to#596736
try those inline skates with the round wheels;
when I finally went to buy them,
they had gone from two balls to three,
surely because of accidents ... but
I'd use them for going uphill (skateboard for downhill

> No it does not. The points on the ground actually rise from the ground 
> before moving on so all the contact points are stationary. And that 
> means they are in focus while the shutter is open. So what you have is a 
> LINE of stationary in focus contact points. No?

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#596883

From"nuny@bid.nes" <Alien8752@gmail.com>
Date2016-09-13 17:14 -0700
Message-ID<b5edb112-90c0-4170-b32d-92ff0f562b04@googlegroups.com>
In reply to#596736
On Monday, September 12, 2016 at 6:29:36 PM UTC-7, benj wrote:
> On 9/9/2016 10:43 PM, nuny@bid.nes wrote:
> > On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
> >> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
> >>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
> >>>
> >>>   There is no "instantaneous". The wheel *moves* while the shutter is
> >>> open, hence the contact patch will move, hence the lowermost spokes will
> >>> be blurred.
> >>>
> >>>   Now, if you want to talk about which spokes will be *least* blurred...
> >>>
> >> Actually, Mark, only the point of the wheel touching the ground which
> >> would be the rim is at rest.
> >
> >   Actually, no, because the shutter can't open *and close*
> > "instantaneously".
> >
> >   The contact patch *moves* while the shutter is open.
> >
> No it does not.

  Yes, it does.  "Contact patch" is that part of the wheel that's in contact with the ground. When the wheel isn't moving, neither is the contact patch. When the wheel *is* moving, so is the contact patch. It has to or the wheel isn't rolling. That's what "moves" means when applied to rolling wheels.

> The points on the ground actually rise from the ground

  And while they're actually rising, they're actually blurring because while they're actually moving the shutter is actually open.

> before moving on so all the contact points are stationary.

  There *is no stationary* while the wheel is moving. Each subsequent point on the rim that comes in contact with the ground *while the wheel is moving* must *also* be moving.

> And that means they are in focus while the shutter is open.

  Briefly, then they're not. While the shutter is still open. That's why they blur.

> So what you have is a LINE of stationary in focus contact points. No?

  No.


  Mark L. Fergerson

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#596893

Frombenj <benj@nobody.net>
Date2016-09-13 21:52 -0400
Message-ID<57d8ad7a$0$43782$c3e8da3$5e5e430d@news.astraweb.com>
In reply to#596883
On 9/13/2016 8:14 PM, nuny@bid.nes wrote:
> On Monday, September 12, 2016 at 6:29:36 PM UTC-7, benj wrote:
>> On 9/9/2016 10:43 PM, nuny@bid.nes wrote:
>>> On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>
>>>>> There is no "instantaneous". The wheel *moves* while the
>>>>> shutter is open, hence the contact patch will move, hence the
>>>>> lowermost spokes will be blurred.
>>>>>
>>>>> Now, if you want to talk about which spokes will be *least*
>>>>> blurred...
>>>>>
>>>> Actually, Mark, only the point of the wheel touching the ground
>>>> which would be the rim is at rest.
>>>
>>> Actually, no, because the shutter can't open *and close*
>>> "instantaneously".
>>>
>>> The contact patch *moves* while the shutter is open.
>>>
>> No it does not.
>
> Yes, it does.  "Contact patch" is that part of the wheel that's in
> contact with the ground. When the wheel isn't moving, neither is the
> contact patch. When the wheel *is* moving, so is the contact patch.
> It has to or the wheel isn't rolling. That's what "moves" means when
> applied to rolling wheels.
>
>> The points on the ground actually rise from the ground
>
> And while they're actually rising, they're actually blurring because
> while they're actually moving the shutter is actually open.
>
>> before moving on so all the contact points are stationary.
>
> There *is no stationary* while the wheel is moving. Each subsequent
> point on the rim that comes in contact with the ground *while the
> wheel is moving* must *also* be moving.

Ahem. So lesse if I got your "logic" here. The ground is stationary. We 
agree with that, right? And the rim of the wheel has points that contact 
the ground. But no points on the wheel are stationary? So you are 
arguing that the wheel is sliding?

>> And that means they are in focus while the shutter is open.
>
> Briefly, then they're not. While the shutter is still open. That's
> why they blur.
>
>> So what you have is a LINE of stationary in focus contact points.
>> No?
>
> No.

So the rim of the wheel is NOT in contact with the ground. Right? Or is 
sliding.

> Mark L. Fergerson
>

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#596903

Fromjimp@specsol.spam.sux.com
Date2016-09-14 05:11 +0000
Message-ID<kp2nad-u39.ln1@mail.specsol.com>
In reply to#596893
benj <benj@nobody.net> wrote:
> On 9/13/2016 8:14 PM, nuny@bid.nes wrote:
>> On Monday, September 12, 2016 at 6:29:36 PM UTC-7, benj wrote:
>>> On 9/9/2016 10:43 PM, nuny@bid.nes wrote:
>>>> On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
>>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>>
>>>>>> There is no "instantaneous". The wheel *moves* while the
>>>>>> shutter is open, hence the contact patch will move, hence the
>>>>>> lowermost spokes will be blurred.
>>>>>>
>>>>>> Now, if you want to talk about which spokes will be *least*
>>>>>> blurred...
>>>>>>
>>>>> Actually, Mark, only the point of the wheel touching the ground
>>>>> which would be the rim is at rest.
>>>>
>>>> Actually, no, because the shutter can't open *and close*
>>>> "instantaneously".
>>>>
>>>> The contact patch *moves* while the shutter is open.
>>>>
>>> No it does not.
>>
>> Yes, it does.  "Contact patch" is that part of the wheel that's in
>> contact with the ground. When the wheel isn't moving, neither is the
>> contact patch. When the wheel *is* moving, so is the contact patch.
>> It has to or the wheel isn't rolling. That's what "moves" means when
>> applied to rolling wheels.
>>
>>> The points on the ground actually rise from the ground
>>
>> And while they're actually rising, they're actually blurring because
>> while they're actually moving the shutter is actually open.
>>
>>> before moving on so all the contact points are stationary.
>>
>> There *is no stationary* while the wheel is moving. Each subsequent
>> point on the rim that comes in contact with the ground *while the
>> wheel is moving* must *also* be moving.
> 
> Ahem. So lesse if I got your "logic" here. The ground is stationary. We 
> agree with that, right? And the rim of the wheel has points that contact 
> the ground. But no points on the wheel are stationary? So you are 
> arguing that the wheel is sliding?

No points on the wheel are stationary if the wheel is rolling.

>>> And that means they are in focus while the shutter is open.
>>
>> Briefly, then they're not. While the shutter is still open. That's
>> why they blur.
>>
>>> So what you have is a LINE of stationary in focus contact points.
>>> No?
>>
>> No.
> 
> So the rim of the wheel is NOT in contact with the ground. Right? Or is 
> sliding.

Obviously the wheel is rolling which means for any real time span
the part of the wheel that is in contact with the ground is continuously
changeing.


-- 
Jim Pennino

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#597094

Frombenj <benj@nobody.net>
Date2016-09-15 17:49 -0400
Message-ID<57db175c$0$31348$c3e8da3$dd9697d2@news.astraweb.com>
In reply to#596903
On 9/14/2016 1:11 AM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 9/13/2016 8:14 PM, nuny@bid.nes wrote:
>>> On Monday, September 12, 2016 at 6:29:36 PM UTC-7, benj wrote:
>>>> On 9/9/2016 10:43 PM, nuny@bid.nes wrote:
>>>>> On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
>>>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>>>
>>>>>>> There is no "instantaneous". The wheel *moves* while the
>>>>>>> shutter is open, hence the contact patch will move, hence the
>>>>>>> lowermost spokes will be blurred.
>>>>>>>
>>>>>>> Now, if you want to talk about which spokes will be *least*
>>>>>>> blurred...
>>>>>>>
>>>>>> Actually, Mark, only the point of the wheel touching the ground
>>>>>> which would be the rim is at rest.
>>>>>
>>>>> Actually, no, because the shutter can't open *and close*
>>>>> "instantaneously".
>>>>>
>>>>> The contact patch *moves* while the shutter is open.
>>>>>
>>>> No it does not.
>>>
>>> Yes, it does.  "Contact patch" is that part of the wheel that's in
>>> contact with the ground. When the wheel isn't moving, neither is the
>>> contact patch. When the wheel *is* moving, so is the contact patch.
>>> It has to or the wheel isn't rolling. That's what "moves" means when
>>> applied to rolling wheels.
>>>
>>>> The points on the ground actually rise from the ground
>>>
>>> And while they're actually rising, they're actually blurring because
>>> while they're actually moving the shutter is actually open.
>>>
>>>> before moving on so all the contact points are stationary.
>>>
>>> There *is no stationary* while the wheel is moving. Each subsequent
>>> point on the rim that comes in contact with the ground *while the
>>> wheel is moving* must *also* be moving.
>>
>> Ahem. So lesse if I got your "logic" here. The ground is stationary. We
>> agree with that, right? And the rim of the wheel has points that contact
>> the ground. But no points on the wheel are stationary? So you are
>> arguing that the wheel is sliding?
>
> No points on the wheel are stationary if the wheel is rolling.

Only true of wheel is sliding and not rolling. If a point is contact 
with the ground, then since the ground is not moving it can't be moving.

>>>> And that means they are in focus while the shutter is open.
>>>
>>> Briefly, then they're not. While the shutter is still open. That's
>>> why they blur.
>>>
>>>> So what you have is a LINE of stationary in focus contact points.
>>>> No?
>>>
>>> No.
>>
>> So the rim of the wheel is NOT in contact with the ground. Right? Or is
>> sliding.
>
> Obviously the wheel is rolling which means for any real time span
> the part of the wheel that is in contact with the ground is continuously
> changeing.

True. In an ideal case the points on the rim touch the ground one after 
another, but since the ground is not moving, any point touching the 
ground can't be moving.

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#597102

Fromjimp@specsol.spam.sux.com
Date2016-09-16 00:50 +0000
Message-ID<j7srad-4qo.ln1@mail.specsol.com>
In reply to#597094
benj <benj@nobody.net> wrote:
> On 9/14/2016 1:11 AM, jimp@specsol.spam.sux.com wrote:
>> benj <benj@nobody.net> wrote:
>>> On 9/13/2016 8:14 PM, nuny@bid.nes wrote:
>>>> On Monday, September 12, 2016 at 6:29:36 PM UTC-7, benj wrote:
>>>>> On 9/9/2016 10:43 PM, nuny@bid.nes wrote:
>>>>>> On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
>>>>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>>>>
>>>>>>>> There is no "instantaneous". The wheel *moves* while the
>>>>>>>> shutter is open, hence the contact patch will move, hence the
>>>>>>>> lowermost spokes will be blurred.
>>>>>>>>
>>>>>>>> Now, if you want to talk about which spokes will be *least*
>>>>>>>> blurred...
>>>>>>>>
>>>>>>> Actually, Mark, only the point of the wheel touching the ground
>>>>>>> which would be the rim is at rest.
>>>>>>
>>>>>> Actually, no, because the shutter can't open *and close*
>>>>>> "instantaneously".
>>>>>>
>>>>>> The contact patch *moves* while the shutter is open.
>>>>>>
>>>>> No it does not.
>>>>
>>>> Yes, it does.  "Contact patch" is that part of the wheel that's in
>>>> contact with the ground. When the wheel isn't moving, neither is the
>>>> contact patch. When the wheel *is* moving, so is the contact patch.
>>>> It has to or the wheel isn't rolling. That's what "moves" means when
>>>> applied to rolling wheels.
>>>>
>>>>> The points on the ground actually rise from the ground
>>>>
>>>> And while they're actually rising, they're actually blurring because
>>>> while they're actually moving the shutter is actually open.
>>>>
>>>>> before moving on so all the contact points are stationary.
>>>>
>>>> There *is no stationary* while the wheel is moving. Each subsequent
>>>> point on the rim that comes in contact with the ground *while the
>>>> wheel is moving* must *also* be moving.
>>>
>>> Ahem. So lesse if I got your "logic" here. The ground is stationary. We
>>> agree with that, right? And the rim of the wheel has points that contact
>>> the ground. But no points on the wheel are stationary? So you are
>>> arguing that the wheel is sliding?
>>
>> No points on the wheel are stationary if the wheel is rolling.
> 
> Only true of wheel is sliding and not rolling. If a point is contact 
> with the ground, then since the ground is not moving it can't be moving.
> 
>>>>> And that means they are in focus while the shutter is open.
>>>>
>>>> Briefly, then they're not. While the shutter is still open. That's
>>>> why they blur.
>>>>
>>>>> So what you have is a LINE of stationary in focus contact points.
>>>>> No?
>>>>
>>>> No.
>>>
>>> So the rim of the wheel is NOT in contact with the ground. Right? Or is
>>> sliding.
>>
>> Obviously the wheel is rolling which means for any real time span
>> the part of the wheel that is in contact with the ground is continuously
>> changeing.
> 
> True. In an ideal case the points on the rim touch the ground one after 
> another, but since the ground is not moving, any point touching the 
> ground can't be moving.
 
All points on the wheel are always moving relative to the ground in any
time period other than zero.

Instantaneous only appears in mathematical equations, not in camera
exposures.
 

-- 
Jim Pennino

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#597114

Frombenj <benj@nobody.net>
Date2016-09-15 21:52 -0400
Message-ID<57db507c$0$31315$c3e8da3$dd9697d2@news.astraweb.com>
In reply to#597102
On 9/15/2016 8:50 PM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 9/14/2016 1:11 AM, jimp@specsol.spam.sux.com wrote:
>>> benj <benj@nobody.net> wrote:
>>>> On 9/13/2016 8:14 PM, nuny@bid.nes wrote:
>>>>> On Monday, September 12, 2016 at 6:29:36 PM UTC-7, benj wrote:
>>>>>> On 9/9/2016 10:43 PM, nuny@bid.nes wrote:
>>>>>>> On Friday, September 9, 2016 at 2:51:31 PM UTC-7, benj wrote:
>>>>>>>> On 9/9/2016 12:08 PM, nuny@bid.nes wrote:
>>>>>>>>> On Monday, August 29, 2016 at 10:08:25 AM UTC-7, 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.
>>>>>>>>>
>>>>>>>>> There is no "instantaneous". The wheel *moves* while the
>>>>>>>>> shutter is open, hence the contact patch will move, hence the
>>>>>>>>> lowermost spokes will be blurred.
>>>>>>>>>
>>>>>>>>> Now, if you want to talk about which spokes will be *least*
>>>>>>>>> blurred...
>>>>>>>>>
>>>>>>>> Actually, Mark, only the point of the wheel touching the ground
>>>>>>>> which would be the rim is at rest.
>>>>>>>
>>>>>>> Actually, no, because the shutter can't open *and close*
>>>>>>> "instantaneously".
>>>>>>>
>>>>>>> The contact patch *moves* while the shutter is open.
>>>>>>>
>>>>>> No it does not.
>>>>>
>>>>> Yes, it does.  "Contact patch" is that part of the wheel that's in
>>>>> contact with the ground. When the wheel isn't moving, neither is the
>>>>> contact patch. When the wheel *is* moving, so is the contact patch.
>>>>> It has to or the wheel isn't rolling. That's what "moves" means when
>>>>> applied to rolling wheels.
>>>>>
>>>>>> The points on the ground actually rise from the ground
>>>>>
>>>>> And while they're actually rising, they're actually blurring because
>>>>> while they're actually moving the shutter is actually open.
>>>>>
>>>>>> before moving on so all the contact points are stationary.
>>>>>
>>>>> There *is no stationary* while the wheel is moving. Each subsequent
>>>>> point on the rim that comes in contact with the ground *while the
>>>>> wheel is moving* must *also* be moving.
>>>>
>>>> Ahem. So lesse if I got your "logic" here. The ground is stationary. We
>>>> agree with that, right? And the rim of the wheel has points that contact
>>>> the ground. But no points on the wheel are stationary? So you are
>>>> arguing that the wheel is sliding?
>>>
>>> No points on the wheel are stationary if the wheel is rolling.
>>
>> Only true of wheel is sliding and not rolling. If a point is contact
>> with the ground, then since the ground is not moving it can't be moving.
>>
>>>>>> And that means they are in focus while the shutter is open.
>>>>>
>>>>> Briefly, then they're not. While the shutter is still open. That's
>>>>> why they blur.
>>>>>
>>>>>> So what you have is a LINE of stationary in focus contact points.
>>>>>> No?
>>>>>
>>>>> No.
>>>>
>>>> So the rim of the wheel is NOT in contact with the ground. Right? Or is
>>>> sliding.
>>>
>>> Obviously the wheel is rolling which means for any real time span
>>> the part of the wheel that is in contact with the ground is continuously
>>> changeing.
>>
>> True. In an ideal case the points on the rim touch the ground one after
>> another, but since the ground is not moving, any point touching the
>> ground can't be moving.
>
> All points on the wheel are always moving relative to the ground in any
> time period other than zero.
>
> Instantaneous only appears in mathematical equations, not in camera
> exposures.

Actually not true, because there will be a LINE of point right along the 
ground the camera sees that are not moving. Of course since the wheel is 
passing through the frame these exposures will be less than that set by 
the camera shutter, but film speed and exposure were not specified. 
Excuse me, nobody knows what film is any more, Lets just say the photo 
array automatically adjusts it's exposure, OK?

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#597120

Fromjimp@specsol.spam.sux.com
Date2016-09-16 04:11 +0000
Message-ID<j08sad-t5q.ln1@mail.specsol.com>
In reply to#597114
benj <benj@nobody.net> wrote:
> On 9/15/2016 8:50 PM, jimp@specsol.spam.sux.com wrote:

<snip>

>> Instantaneous only appears in mathematical equations, not in camera
>> exposures.
> 
> Actually not true,

Yes true.

> because there will be a LINE of point right along the 

A line and a point are two different things.

> ground the camera sees that are not moving. Of course since the wheel is 
> passing through the frame these exposures will be less than that set by 
> the camera shutter, but film speed and exposure were not specified. 
> Excuse me, nobody knows what film is any more, Lets just say the photo 
> array automatically adjusts it's exposure, OK?

Gibbering nonsense.

There are no "these exposures", there is only one exposure during the
time the shutter is open.

During the time the shutter is open, the image is the sum of everything
that happened during that time and is limited only by the saturation
limits of the medium, whether it be digital or film.
 

-- 
Jim Pennino

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#597217

Frombenj <benj@nobody.net>
Date2016-09-16 16:58 -0400
Message-ID<57dc5cfa$0$4527$c3e8da3$b280bf18@news.astraweb.com>
In reply to#597120
On 9/16/2016 12:11 AM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 9/15/2016 8:50 PM, jimp@specsol.spam.sux.com wrote:
>
> <snip>
>
>>> Instantaneous only appears in mathematical equations, not in camera
>>> exposures.
>>
>> Actually not true,
>
> Yes true.
>
>> because there will be a LINE of point right along the
>
> A line and a point are two different things.
>
>> ground the camera sees that are not moving. Of course since the wheel is
>> passing through the frame these exposures will be less than that set by
>> the camera shutter, but film speed and exposure were not specified.
>> Excuse me, nobody knows what film is any more, Lets just say the photo
>> array automatically adjusts it's exposure, OK?
>
> Gibbering nonsense.
>
> There are no "these exposures", there is only one exposure during the
> time the shutter is open.

Drooling senile nonsense. When the image moves in the frame it is no 
longer exposing the sensor.

> During the time the shutter is open, the image is the sum of everything
> that happened during that time and is limited only by the saturation
> limits of the medium, whether it be digital or film.

Yadda yadda yadda. YEah you are SO smart and know it all about 
photography. Wonder where you get your film and developer these days. We 
all are impressed with how much you know.

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#597240

Fromjimp@specsol.spam.sux.com
Date2016-09-16 21:40 +0000
Message-ID<je5uad-5b3.ln1@mail.specsol.com>
In reply to#597217
benj <benj@nobody.net> wrote:
> On 9/16/2016 12:11 AM, jimp@specsol.spam.sux.com wrote:
>> benj <benj@nobody.net> wrote:
>>> On 9/15/2016 8:50 PM, jimp@specsol.spam.sux.com wrote:
>>
>> <snip>
>>
>>>> Instantaneous only appears in mathematical equations, not in camera
>>>> exposures.
>>>
>>> Actually not true,
>>
>> Yes true.
>>
>>> because there will be a LINE of point right along the
>>
>> A line and a point are two different things.
>>
>>> ground the camera sees that are not moving. Of course since the wheel is
>>> passing through the frame these exposures will be less than that set by
>>> the camera shutter, but film speed and exposure were not specified.
>>> Excuse me, nobody knows what film is any more, Lets just say the photo
>>> array automatically adjusts it's exposure, OK?
>>
>> Gibbering nonsense.
>>
>> There are no "these exposures", there is only one exposure during the
>> time the shutter is open.
> 
> Drooling senile nonsense. When the image moves in the frame it is no 
> longer exposing the sensor.

Drooling senile nonsense.

The image is exposed the entire time the shutter is open, which means
the final image is the sum of whatever happed during the exposure time.

>> During the time the shutter is open, the image is the sum of everything
>> that happened during that time and is limited only by the saturation
>> limits of the medium, whether it be digital or film.
> 
> Yadda yadda yadda. YEah you are SO smart and know it all about 
> photography. Wonder where you get your film and developer these days. We 
> all are impressed with how much you know.
 
FYI back when I was using film I did all my devloping and printing 
myself starting at about age 12. My favorite film camera was a 4X5"
press camera. Infrared woodland scenery with that camera was pretty
impressive and you could blow up a 4X5 negative almost forever before
seeing grain.

You are utterly clueless about imaging of any kind and are going into
attack mode. 

Save yourself further embarrassment.

-- 
Jim Pennino

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#597262

Frombenj <benj@nobody.net>
Date2016-09-16 20:56 -0400
Message-ID<57dc94e9$0$43888$c3e8da3$5e5e430d@news.astraweb.com>
In reply to#597240
On 9/16/2016 5:40 PM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 9/16/2016 12:11 AM, jimp@specsol.spam.sux.com wrote:
>>> benj <benj@nobody.net> wrote:
>>>> On 9/15/2016 8:50 PM, jimp@specsol.spam.sux.com wrote:
>>>
>>> <snip>
>>>
>>>>> Instantaneous only appears in mathematical equations, not in camera
>>>>> exposures.
>>>>
>>>> Actually not true,
>>>
>>> Yes true.
>>>
>>>> because there will be a LINE of point right along the
>>>
>>> A line and a point are two different things.
>>>
>>>> ground the camera sees that are not moving. Of course since the wheel is
>>>> passing through the frame these exposures will be less than that set by
>>>> the camera shutter, but film speed and exposure were not specified.
>>>> Excuse me, nobody knows what film is any more, Lets just say the photo
>>>> array automatically adjusts it's exposure, OK?
>>>
>>> Gibbering nonsense.
>>>
>>> There are no "these exposures", there is only one exposure during the
>>> time the shutter is open.
>>
>> Drooling senile nonsense. When the image moves in the frame it is no
>> longer exposing the sensor.
>
> Drooling senile nonsense.

No imagination. Plagiarism.

> The image is exposed the entire time the shutter is open, which means
> the final image is the sum of whatever happed during the exposure time.

Drooling nonsense. Set up your 4x5 press camera. Focus on a road. A car 
comes down the road. Stops in front of the camera for a minute. Then 
goes on. What is the exposure time of the car? Is it the whole time the 
shutter was open? You need to quite before you embarrass yourself further.

>>> During the time the shutter is open, the image is the sum of everything
>>> that happened during that time and is limited only by the saturation
>>> limits of the medium, whether it be digital or film.
>>
>> Yadda yadda yadda. YEah you are SO smart and know it all about
>> photography. Wonder where you get your film and developer these days. We
>> all are impressed with how much you know.
>
> FYI back when I was using film I did all my devloping and printing
> myself starting at about age 12. My favorite film camera was a 4X5"
> press camera. Infrared woodland scenery with that camera was pretty
> impressive and you could blow up a 4X5 negative almost forever before
> seeing grain.
>
> You are utterly clueless about imaging of any kind and are going into
> attack mode.
>
> Save yourself further embarrassment.

You pretend to have a huge ego but HVAC has got you beat in spades!

You want a film size war? I had SEVERAL 8X10 view cameras. You can 
REALLY enlarge those babies! I was a professional photographer even in 
high school making money doing weddings and the like. So Chimp tell me 
just how much color film you developed and how many color prints did you 
make? You really need to stop trying to "one-up" your betters. You can't 
possibly win and you only embarrass yourself. I had a couple press 
cameras but really never liked them. I much preferred my old Graflex for 
large format film.

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