Could use a stronger micro 4/3rds body

Discussion in 'Digital Photography' started by RichA, Nov 20, 2011.

  1. RichA

    RichA Guest

    All the m4/3rds bodies now are plastic. Some are "skinnned" in sheet
    aluminum, but structurally, they are plastic. Even if you support
    larger lenses by the lens, there comes a time when you'll want the
    camera to support them, at least for a short time. Plastic does work
    better when the body panels are small than if they are large (less
    flexture), and small bodies are a 4/3rds characteristic, but for
    larger lenses, it would be good to have a metal body. Sony has done
    it with the NEX, so the m4/3rds people should be able to as well.
    RichA, Nov 20, 2011
    #1
    1. Advertising

  2. RichA

    Bruce Guest

    RichA <> wrote:
    >
    >All the m4/3rds bodies now are plastic. Some are "skinnned" in sheet
    >aluminum, but structurally, they are plastic. Even if you support
    >larger lenses by the lens, there comes a time when you'll want the
    >camera to support them, at least for a short time.



    Why? Even with APS-C and full frame DSLRs, it makes sense to support
    larger lenses and clip the camera body onto the bayonet at the back.
    If using heavy lenses, the same would make sense with micro 4/3rds.


    >Plastic does work
    >better when the body panels are small than if they are large (less
    >flexture), and small bodies are a 4/3rds characteristic, but for
    >larger lenses, it would be good to have a metal body.



    No point. See above.


    >Sony has done it with the NEX



    The NEX-3 and C3 are plastic. The NEX-5 and 5N are plastic with a
    metal skin. I don't know about the NEX-7, but I guess that it follows
    the same construction as the NEX-5 and 5N.


    >so the m4/3rds people should be able to as well.



    No point. See above.
    Bruce, Nov 20, 2011
    #2
    1. Advertising

  3. RichA

    Bruce Guest

    Rich <> wrote:
    >Bruce <> wrote in
    >news::
    >Didn't quite get your point about bayonetting. Attaching the lens??
    >Most people when carrying cameras let them hang, by the body, from a
    >strap.



    That's because most people use lightweight lenses, such as the Olympus
    M.Zuiko 40-200mm and the Panasonic 45-200mm. Even the Panasonic
    100-300mm is a fairly light lens. That's just one benefit of plastic.


    >This is not advisible with even moderately heavy lenses and a
    >m4/3rd body.



    It's fine with the lenses stated above, which are probably the longest
    lenses used by 99% of m4/3 users. Anything longer, or heavier, and
    you should support the lens, not the camera.
    Bruce, Nov 21, 2011
    #3
  4. RichA

    RichA Guest

    On Nov 20, 10:02 pm, Eric Stevens <> wrote:
    > On Sun, 20 Nov 2011 10:43:38 -0800 (PST), RichA <>
    > wrote:
    >
    > >All the m4/3rds bodies now are plastic.  Some are "skinnned" in sheet
    > >aluminum, but structurally, they are plastic.  Even if you support
    > >larger lenses by the lens, there comes a time when you'll want the
    > >camera to support them, at least for a short time.  Plastic does work
    > >better when the body panels are small than if they are large (less
    > >flexture), and small bodies are a 4/3rds characteristic, but for
    > >larger lenses, it would be good to have a metal body.  Sony has done
    > >it with the NEX, so the m4/3rds people should be able to as well.

    >
    > If the metal skin is bonded to the plastic, the two materials work
    > together. The metal is much more rigid than the plastic and will
    > therefore carry the majority of any applied load. This means that in
    > normal use the user is handling a camera substantially as rigid as if
    > it were metal. This only changes when the metal delaminates from the
    > plastic, usually from being subject to excessive force.
    >


    Or temperature changes where the plastic expands and contracts a lot
    more than the metal.
    RichA, Nov 21, 2011
    #4
  5. RichA

    Bruce Guest

    RichA <> wrote:

    >On Nov 20, 10:02 pm, Eric Stevens <> wrote:
    >> On Sun, 20 Nov 2011 10:43:38 -0800 (PST), RichA <>
    >> wrote:
    >>
    >> >All the m4/3rds bodies now are plastic.  Some are "skinnned" in sheet
    >> >aluminum, but structurally, they are plastic.  Even if you support
    >> >larger lenses by the lens, there comes a time when you'll want the
    >> >camera to support them, at least for a short time.  Plastic does work
    >> >better when the body panels are small than if they are large (less
    >> >flexture), and small bodies are a 4/3rds characteristic, but for
    >> >larger lenses, it would be good to have a metal body.  Sony has done
    >> >it with the NEX, so the m4/3rds people should be able to as well.

    >>
    >> If the metal skin is bonded to the plastic, the two materials work
    >> together. The metal is much more rigid than the plastic and will
    >> therefore carry the majority of any applied load. This means that in
    >> normal use the user is handling a camera substantially as rigid as if
    >> it were metal. This only changes when the metal delaminates from the
    >> plastic, usually from being subject to excessive force.
    >>

    >
    >Or temperature changes where the plastic expands and contracts a lot
    >more than the metal.



    Or, more likely, temperature changes where the plastic expands and
    contracts a lot *LESS* than the metal.
    Bruce, Nov 21, 2011
    #5
  6. RichA

    RichA Guest

    On Nov 21, 7:03 am, Bruce <> wrote:
    > Rich <> wrote:
    > >Bruce <> wrote in
    > >news::
    > >Didn't quite get your point about bayonetting.  Attaching the lens??
    > >Most people when carrying cameras let them hang, by the body, from a
    > >strap.

    >
    > That's because most people use lightweight lenses, such as the Olympus
    > M.Zuiko 40-200mm and the Panasonic 45-200mm.  Even the Panasonic
    > 100-300mm is a fairly light lens.  That's just one benefit of plastic.
    >
    > >This is not advisible with even moderately heavy lenses and a
    > >m4/3rd body.

    >
    > It's fine with the lenses stated above, which are probably the longest
    > lenses used by 99% of m4/3 users.  Anything longer, or heavier, and
    > you should support the lens, not the camera.


    Kind of awkward, if you do it for a long time. My most comfortable
    DSLR when used with any lens was the Olympus E-1, which allowed you to
    (thanks to the deep grip) dangle it from the tips of your fingers if
    you wanted. Usually, with a normal sized DSLR (say a D300) you could
    use all but the heaviest lenses by simply leveraging with the grip
    (especially if you had an optional battery grip attached). A 24-70mm
    f2.8 was supportable in this way. Beyond that, you need to support
    the lens too.
    However, the big difference when it comes to lens support is how much
    weight are you taking? With a m4/3rds body and a larger lens, you are
    supporting almost all the lens and some of the camera weight when you
    support the lens. You actually are applying and upward pressure to
    the lens (usually the focus ring) and this is somewhat questionable as
    focusing rings are not meant to have unequal pressure applied to
    them. With a grippable DSLR, you can pull backwards on the DSLR grip
    thereby taking some of the lens weight off the hand supporting it,
    which usually means zooming or focusing manually is easier.
    The heaviest thing I had on a Panasonic G1 was a Nikon Q series 135mm
    f2.8. One of the strap eyelets unscrewed itself (though not when that
    lens was on the camera) but that is a known flaw with the G1/GH1.
    RichA, Nov 21, 2011
    #6
  7. RichA

    Bruce Guest

    RichA <> wrote:
    >On Nov 21, 7:03 am, Bruce <> wrote:
    >> Rich <> wrote:
    >> >Bruce <> wrote in
    >> >news::
    >> >Didn't quite get your point about bayonetting.  Attaching the lens??
    >> >Most people when carrying cameras let them hang, by the body, from a
    >> >strap.

    >>
    >> That's because most people use lightweight lenses, such as the Olympus
    >> M.Zuiko 40-200mm and the Panasonic 45-200mm.  Even the Panasonic
    >> 100-300mm is a fairly light lens.  That's just one benefit of plastic.
    >>
    >> >This is not advisible with even moderately heavy lenses and a
    >> >m4/3rd body.

    >>
    >> It's fine with the lenses stated above, which are probably the longest
    >> lenses used by 99% of m4/3 users.  Anything longer, or heavier, and
    >> you should support the lens, not the camera.

    >
    >Kind of awkward, if you do it for a long time. My most comfortable
    >DSLR when used with any lens was the Olympus E-1, which allowed you to
    >(thanks to the deep grip) dangle it from the tips of your fingers if
    >you wanted. Usually, with a normal sized DSLR (say a D300) you could
    >use all but the heaviest lenses by simply leveraging with the grip
    >(especially if you had an optional battery grip attached). A 24-70mm
    >f2.8 was supportable in this way. Beyond that, you need to support
    >the lens too.
    >However, the big difference when it comes to lens support is how much
    >weight are you taking? With a m4/3rds body and a larger lens, you are
    >supporting almost all the lens and some of the camera weight when you
    >support the lens. You actually are applying and upward pressure to
    >the lens (usually the focus ring) and this is somewhat questionable as
    >focusing rings are not meant to have unequal pressure applied to
    >them. With a grippable DSLR, you can pull backwards on the DSLR grip
    >thereby taking some of the lens weight off the hand supporting it,
    >which usually means zooming or focusing manually is easier.
    >The heaviest thing I had on a Panasonic G1 was a Nikon Q series 135mm
    >f2.8. One of the strap eyelets unscrewed itself (though not when that
    >lens was on the camera) but that is a known flaw with the G1/GH1.



    People buy m4/3 for its lightness and compactness. If you want to
    start carrying around heavy lenses, you should perhaps re-evaluate
    whether m4/3 is the right system for you.

    I don't know of any m4/3 lenses that are heavy enough to cause any
    concern about the strength of the lens mount on the camera. If you
    are using long and/or heavy legacy lenses, you should primarily
    support the lens and treat the m4/3 camera body as a relatively
    lightweight attachment to the rear of that lens.

    I realise I am repeating myself, but that's because there isn't any
    more to say. You are arguing about a non-problem.
    Bruce, Nov 21, 2011
    #7
  8. RichA

    PeterN Guest

    On 11/22/2011 3:25 AM, Eric Stevens wrote:
    > On Mon, 21 Nov 2011 21:30:24 -0600, Rich<> wrote:

    <snip>>

    >>
    >> The fact they don't turn as smoothly when you allow the weight of a lens
    >> to press down pretty much proves it. But feel free to experiment.

    >
    > It doesn't prove that "focusing rings are not meant to have unequal
    > pressure applied to them". All it does is prove that frictional forces
    > increase when you increase the forces applied to the focusing ring;
    > but I would expect that. It says nothing at all about whether or not
    > the focusing ring is designed to withstand any particular system of
    > forces.
    >
    > Regards,
    >
    > Eric Stevens


    Eric, I'm sure you realize you are contradicting the opinion of the
    world's pre=eminent optical design engineer. It can tell you what's
    wrong with any product, just by looking at a photo, or someone else's
    description.

    --
    Peter
    PeterN, Nov 22, 2011
    #8
  9. RichA

    Bruce Guest

    Rich <> wrote:
    >Eric Stevens <> wrote in
    >news::
    >> On Mon, 21 Nov 2011 08:11:08 -0800 (PST), RichA <>
    >> wrote:
    >>>Kind of awkward, if you do it for a long time. My most comfortable
    >>>DSLR when used with any lens was the Olympus E-1, which allowed you to
    >>>(thanks to the deep grip) dangle it from the tips of your fingers if
    >>>you wanted. Usually, with a normal sized DSLR (say a D300) you could
    >>>use all but the heaviest lenses by simply leveraging with the grip
    >>>(especially if you had an optional battery grip attached). A 24-70mm
    >>>f2.8 was supportable in this way. Beyond that, you need to support
    >>>the lens too.
    >>>However, the big difference when it comes to lens support is how much
    >>>weight are you taking? With a m4/3rds body and a larger lens, you are
    >>>supporting almost all the lens and some of the camera weight when you
    >>>support the lens. You actually are applying and upward pressure to
    >>>the lens (usually the focus ring) and this is somewhat questionable as
    >>>focusing rings are not meant to have unequal pressure applied to
    >>>them.

    >>
    >> Who says? Apart from you, that is.
    >>

    >
    >The fact they don't turn as smoothly when you allow the weight of a lens
    >to press down pretty much proves it. But feel free to experiment.



    So now you're imagining a lens that is heavy enough to distort the
    lens mount of a m4/3 camera body. but whose focusing ring is so flimsy
    that it bends.

    It's pure fantasy.
    Bruce, Nov 22, 2011
    #9
  10. RichA

    RichA Guest

    On Nov 22, 3:25 am, Eric Stevens <> wrote:
    > On Mon, 21 Nov 2011 21:30:24 -0600, Rich <> wrote:
    > >Eric Stevens <> wrote in
    > >news::

    >
    > >> On Mon, 21 Nov 2011 08:11:08 -0800 (PST), RichA <>
    > >> wrote:

    >
    > >>>On Nov 21, 7:03 am, Bruce <> wrote:
    > >>>> Rich <> wrote:
    > >>>> >Bruce <> wrote in
    > >>>> >news::
    > >>>> >Didn't quite get your point about bayonetting.  Attaching the lens??
    > >>>> >Most people when carrying cameras let them hang, by the body, from a
    > >>>> >strap.

    >
    > >>>> That's because most people use lightweight lenses, such as the

    > >Olympus
    > >>>> M.Zuiko 40-200mm and the Panasonic 45-200mm.  Even the Panasonic
    > >>>> 100-300mm is a fairly light lens.  That's just one benefit of

    > >plastic.

    >
    > >>>> >This is not advisible with even moderately heavy lenses and a
    > >>>> >m4/3rd body.

    >
    > >>>> It's fine with the lenses stated above, which are probably the

    > >longest
    > >>>> lenses used by 99% of m4/3 users.  Anything longer, or heavier, and
    > >>>> you should support the lens, not the camera.

    >
    > >>>Kind of awkward, if you do it for a long time. My most comfortable
    > >>>DSLR when used with any lens was the Olympus E-1, which allowed you to
    > >>>(thanks to the deep grip) dangle it from the tips of your fingers if
    > >>>you wanted.  Usually, with a normal sized DSLR (say a D300) you could
    > >>>use all but the heaviest lenses by simply leveraging with the grip
    > >>>(especially if you had an optional battery grip attached).  A 24-70mm
    > >>>f2.8 was supportable in this way.  Beyond that, you need to support
    > >>>the lens too.
    > >>>However, the big difference when it comes to lens support is how much
    > >>>weight are you taking?  With a m4/3rds body and a larger lens, you are
    > >>>supporting almost all the lens and some of the camera weight when you
    > >>>support the lens.  You actually are applying and upward pressure to
    > >>>the lens (usually the focus ring) and this is somewhat questionable as
    > >>>focusing rings are not meant to have unequal pressure applied to
    > >>>them.

    >
    > >> Who says? Apart from you, that is.

    >
    > >The fact they don't turn as smoothly when you allow the weight of a lens
    > >to press down pretty much proves it.  But feel free to experiment.

    >
    > It doesn't prove that "focusing rings are not meant to have unequal
    > pressure applied to them". All it does is prove that frictional forces
    > increase when you increase the forces applied to the focusing ring;
    > but I would expect that. It says nothing at all about whether or not
    > the focusing ring is designed to withstand any particular system of
    > forces.


    Withstand? As in fail or not fail? I said nothing of the kind. How
    well the zoom or focus ring work depends on even or uneven pressure on
    them.
    RichA, Nov 22, 2011
    #10
  11. RichA

    RichA Guest

    On Nov 22, 5:51 am, PeterN <> wrote:
    > On 11/22/2011 3:25 AM, Eric Stevens wrote:> On Mon, 21 Nov 2011 21:30:24 -0600, Rich<>  wrote:
    >
    > <snip>>
    >
    >
    >
    > >> The fact they don't turn as smoothly when you allow the weight of a lens
    > >> to press down pretty much proves it.  But feel free to experiment.

    >
    > > It doesn't prove that "focusing rings are not meant to have unequal
    > > pressure applied to them". All it does is prove that frictional forces
    > > increase when you increase the forces applied to the focusing ring;
    > > but I would expect that. It says nothing at all about whether or not
    > > the focusing ring is designed to withstand any particular system of
    > > forces.

    >
    > > Regards,

    >
    > > Eric Stevens

    >
    > Eric, I'm sure you realize you are contradicting the opinion of the
    > world's pre=eminent optical design engineer. It can tell you what's
    > wrong with any product, just by looking at a photo, or someone else's
    > description.
    >
    > --
    > Peter


    Optical engineering is different than mechanical engineering.
    RichA, Nov 22, 2011
    #11
  12. RichA

    RichA Guest

    On Nov 22, 7:03 am, Bruce <> wrote:
    > Rich <> wrote:
    > >Eric Stevens <> wrote in
    > >news::
    > >> On Mon, 21 Nov 2011 08:11:08 -0800 (PST), RichA <>
    > >> wrote:
    > >>>Kind of awkward, if you do it for a long time. My most comfortable
    > >>>DSLR when used with any lens was the Olympus E-1, which allowed you to
    > >>>(thanks to the deep grip) dangle it from the tips of your fingers if
    > >>>you wanted.  Usually, with a normal sized DSLR (say a D300) you could
    > >>>use all but the heaviest lenses by simply leveraging with the grip
    > >>>(especially if you had an optional battery grip attached).  A 24-70mm
    > >>>f2.8 was supportable in this way.  Beyond that, you need to support
    > >>>the lens too.
    > >>>However, the big difference when it comes to lens support is how much
    > >>>weight are you taking?  With a m4/3rds body and a larger lens, you are
    > >>>supporting almost all the lens and some of the camera weight when you
    > >>>support the lens.  You actually are applying and upward pressure to
    > >>>the lens (usually the focus ring) and this is somewhat questionable as
    > >>>focusing rings are not meant to have unequal pressure applied to
    > >>>them.

    >
    > >> Who says? Apart from you, that is.

    >
    > >The fact they don't turn as smoothly when you allow the weight of a lens
    > >to press down pretty much proves it.  But feel free to experiment.

    >
    > So now you're imagining a lens that is heavy enough to distort the
    > lens mount of a m4/3 camera body. but whose focusing ring is so flimsy
    > that it bends.
    >
    > It's pure fantasy.


    Doesn't have to bend. Just has to have enough unequal pressure
    applied to make it work less smoothly. This results in more
    difficulty achieving fine focus. High-end telescopes actually have
    adjustment mechanism designed to compensate for when things like heavy
    cameras are attached to the focusers, so they don't bind. Camera
    lenses do not have these adjustments. The problem is made worse still
    by using fast lenses that are not only heavier, but require more
    delicate manual focusing because of shallow DOF.
    RichA, Nov 22, 2011
    #12
  13. RichA

    Bruce Guest

    RichA <> wrote:

    >On Nov 22, 7:03 am, Bruce <> wrote:
    >> Rich <> wrote:
    >> >Eric Stevens <> wrote in
    >> >news::
    >> >> On Mon, 21 Nov 2011 08:11:08 -0800 (PST), RichA <>
    >> >> wrote:
    >> >>>Kind of awkward, if you do it for a long time. My most comfortable
    >> >>>DSLR when used with any lens was the Olympus E-1, which allowed you to
    >> >>>(thanks to the deep grip) dangle it from the tips of your fingers if
    >> >>>you wanted.  Usually, with a normal sized DSLR (say a D300) you could
    >> >>>use all but the heaviest lenses by simply leveraging with the grip
    >> >>>(especially if you had an optional battery grip attached).  A 24-70mm
    >> >>>f2.8 was supportable in this way.  Beyond that, you need to support
    >> >>>the lens too.
    >> >>>However, the big difference when it comes to lens support is how much
    >> >>>weight are you taking?  With a m4/3rds body and a larger lens, you are
    >> >>>supporting almost all the lens and some of the camera weight when you
    >> >>>support the lens.  You actually are applying and upward pressure to
    >> >>>the lens (usually the focus ring) and this is somewhat questionable as
    >> >>>focusing rings are not meant to have unequal pressure applied to
    >> >>>them.

    >>
    >> >> Who says? Apart from you, that is.

    >>
    >> >The fact they don't turn as smoothly when you allow the weight of a lens
    >> >to press down pretty much proves it.  But feel free to experiment.

    >>
    >> So now you're imagining a lens that is heavy enough to distort the
    >> lens mount of a m4/3 camera body. but whose focusing ring is so flimsy
    >> that it bends.
    >>
    >> It's pure fantasy.

    >
    >Doesn't have to bend. Just has to have enough unequal pressure
    >applied to make it work less smoothly.



    If it doesn't bend, it cannot work less smoothly.

    As I said, this is pure fantasy. You are making the whole thing up.
    Bruce, Nov 22, 2011
    #13
  14. RichA

    PeterN Guest

    On 11/22/2011 8:37 AM, RichA wrote:
    > On Nov 22, 5:51 am, PeterN<> wrote:
    >> On 11/22/2011 3:25 AM, Eric Stevens wrote:> On Mon, 21 Nov 2011 21:30:24 -0600, Rich<> wrote:
    >>
    >> <snip>>
    >>
    >>
    >>
    >>>> The fact they don't turn as smoothly when you allow the weight of a lens
    >>>> to press down pretty much proves it. But feel free to experiment.

    >>
    >>> It doesn't prove that "focusing rings are not meant to have unequal
    >>> pressure applied to them". All it does is prove that frictional forces
    >>> increase when you increase the forces applied to the focusing ring;
    >>> but I would expect that. It says nothing at all about whether or not
    >>> the focusing ring is designed to withstand any particular system of
    >>> forces.

    >>
    >>> Regards,

    >>
    >>> Eric Stevens

    >>
    >> Eric, I'm sure you realize you are contradicting the opinion of the
    >> world's pre=eminent optical design engineer. It can tell you what's
    >> wrong with any product, just by looking at a photo, or someone else's
    >> description.
    >>
    >> --
    >> Peter

    >
    > Optical engineering is different than mechanical engineering.


    And camels are mammals.
    You have never described your qualifications in mechanical engineering;

    marketing;

    corporate management.

    You have expressed unsupported opinions on all the above. Yet, you have
    NEVER given a direct answer to questions about your qualifications.
    Any normal person who receives the amount of ridicule you do would have
    crawled back into his shell, or mommy's basement.
    Here is your chance for redemption.

    --
    Peter
    PeterN, Nov 22, 2011
    #14
  15. RichA

    RichA Guest

    On Nov 22, 8:50 am, Bruce <> wrote:
    > RichA <> wrote:
    > >On Nov 22, 7:03 am, Bruce <> wrote:
    > >> Rich <> wrote:
    > >> >Eric Stevens <> wrote in
    > >> >news::
    > >> >> On Mon, 21 Nov 2011 08:11:08 -0800 (PST), RichA <>
    > >> >> wrote:
    > >> >>>Kind of awkward, if you do it for a long time. My most comfortable
    > >> >>>DSLR when used with any lens was the Olympus E-1, which allowed youto
    > >> >>>(thanks to the deep grip) dangle it from the tips of your fingers if
    > >> >>>you wanted.  Usually, with a normal sized DSLR (say a D300) you could
    > >> >>>use all but the heaviest lenses by simply leveraging with the grip
    > >> >>>(especially if you had an optional battery grip attached).  A 24-70mm
    > >> >>>f2.8 was supportable in this way.  Beyond that, you need to support
    > >> >>>the lens too.
    > >> >>>However, the big difference when it comes to lens support is how much
    > >> >>>weight are you taking?  With a m4/3rds body and a larger lens, you are
    > >> >>>supporting almost all the lens and some of the camera weight when you
    > >> >>>support the lens.  You actually are applying and upward pressure to
    > >> >>>the lens (usually the focus ring) and this is somewhat questionableas
    > >> >>>focusing rings are not meant to have unequal pressure applied to
    > >> >>>them.

    >
    > >> >> Who says? Apart from you, that is.

    >
    > >> >The fact they don't turn as smoothly when you allow the weight of a lens
    > >> >to press down pretty much proves it.  But feel free to experiment.

    >
    > >> So now you're imagining a lens that is heavy enough to distort the
    > >> lens mount of a m4/3 camera body. but whose focusing ring is so flimsy
    > >> that it bends.

    >
    > >> It's pure fantasy.

    >
    > >Doesn't have to bend.  Just has to have enough unequal pressure
    > >applied to make it work less smoothly.

    >
    > If it doesn't bend, it cannot work less smoothly.
    >
    > As I said, this is pure fantasy.  You are making the whole thing up.


    There is a tolerance between a focusing sleeve and the inner sleeve it
    rides on. That slack is taken up when pressure is applied to one
    "side." The pressure increases friction which increases focus
    tension, which makes focusing less smooth.
    RichA, Nov 22, 2011
    #15
  16. RichA

    RichA Guest

    On Nov 22, 8:59 am, PeterN <> wrote:
    > On 11/22/2011 8:37 AM, RichA wrote:
    >
    >
    >
    >
    >
    >
    >
    >
    >
    > > On Nov 22, 5:51 am, PeterN<>  wrote:
    > >> On 11/22/2011 3:25 AM, Eric Stevens wrote:>  On Mon, 21 Nov 2011 21:30:24 -0600, Rich<>    wrote:

    >
    > >> <snip>>

    >
    > >>>> The fact they don't turn as smoothly when you allow the weight of a lens
    > >>>> to press down pretty much proves it.  But feel free to experiment.

    >
    > >>> It doesn't prove that "focusing rings are not meant to have unequal
    > >>> pressure applied to them". All it does is prove that frictional forces
    > >>> increase when you increase the forces applied to the focusing ring;
    > >>> but I would expect that. It says nothing at all about whether or not
    > >>> the focusing ring is designed to withstand any particular system of
    > >>> forces.

    >
    > >>> Regards,

    >
    > >>> Eric Stevens

    >
    > >> Eric, I'm sure you realize you are contradicting the opinion of the
    > >> world's pre=eminent optical design engineer. It can tell you what's
    > >> wrong with any product, just by looking at a photo, or someone else's
    > >> description.

    >
    > >> --
    > >> Peter

    >
    > > Optical engineering is different than mechanical engineering.

    >
    > And camels are mammals.
    > You have never described your qualifications in mechanical engineering;
    >
    > marketing;
    >
    > corporate management.
    >
    > You have expressed unsupported opinions on all the above. Yet, you have
    > NEVER given a direct answer to questions about your qualifications.
    > Any normal person who receives the amount of ridicule you do would have
    > crawled back into his shell, or mommy's basement.


    Keep wishing, you reactionary pussy.
    RichA, Nov 22, 2011
    #16
  17. RichA

    Bruce Guest

    RichA <> wrote:
    >On Nov 22, 8:50 am, Bruce <> wrote:
    >>
    >> If it doesn't bend, it cannot work less smoothly.
    >>
    >> As I said, this is pure fantasy.  You are making the whole thing up.

    >
    >There is a tolerance between a focusing sleeve and the inner sleeve it
    >rides on. That slack is taken up when pressure is applied to one
    >"side." The pressure increases friction which increases focus
    >tension, which makes focusing less smooth.



    You have a problem, and it has nothing to do with the focusing ring
    nor the camera's lens mount. The problem is something you perceive
    but it doesn't actually exist.

    If a lens is heavy enough to cause you concern about distorting the
    camera's lens mount, you should be taking care to support the lens. If
    a lens is heavy enough to cause you concern about distorting the
    camera's lens mount, it is likely to be a strongly made lens with a
    focusing ring that doesn't distort.

    If there is a problem with the focusing ring when you are using it to
    support the weight of the lens, then you shouldn't be using it to
    support the weight of the lens. The lens should be supported by some
    other means - one that doesn't place stress on the focusing ring.

    There are no end of products available that enable heavy lenses to be
    properly supported without placing undue stress either on the camera's
    lens mount or on the zoom, focusing or aperture rings. Use them, and
    you won't have a problem; in fact, you won't even have to imagine that
    there is a problem.
    Bruce, Nov 22, 2011
    #17
  18. RichA

    PeterN Guest

    On 11/22/2011 12:36 PM, RichA wrote:
    > On Nov 22, 8:59 am, PeterN<> wrote:
    >> On 11/22/2011 8:37 AM, RichA wrote:
    >>
    >>
    >>
    >>
    >>
    >>
    >>
    >>
    >>
    >>> On Nov 22, 5:51 am, PeterN<> wrote:
    >>>> On 11/22/2011 3:25 AM, Eric Stevens wrote:> On Mon, 21 Nov 2011 21:30:24 -0600, Rich<> wrote:

    >>
    >>>> <snip>>

    >>
    >>>>>> The fact they don't turn as smoothly when you allow the weight of a lens
    >>>>>> to press down pretty much proves it. But feel free to experiment.

    >>
    >>>>> It doesn't prove that "focusing rings are not meant to have unequal
    >>>>> pressure applied to them". All it does is prove that frictional forces
    >>>>> increase when you increase the forces applied to the focusing ring;
    >>>>> but I would expect that. It says nothing at all about whether or not
    >>>>> the focusing ring is designed to withstand any particular system of
    >>>>> forces.

    >>
    >>>>> Regards,

    >>
    >>>>> Eric Stevens

    >>
    >>>> Eric, I'm sure you realize you are contradicting the opinion of the
    >>>> world's pre=eminent optical design engineer. It can tell you what's
    >>>> wrong with any product, just by looking at a photo, or someone else's
    >>>> description.

    >>
    >>>> --
    >>>> Peter

    >>
    >>> Optical engineering is different than mechanical engineering.

    >>
    >> And camels are mammals.
    >> You have never described your qualifications in mechanical engineering;
    >>
    >> marketing;
    >>
    >> corporate management.
    >>
    >> You have expressed unsupported opinions on all the above. Yet, you have
    >> NEVER given a direct answer to questions about your qualifications.
    >> Any normal person who receives the amount of ridicule you do would have
    >> crawled back into his shell, or mommy's basement.

    >
    > Keep wishing, you reactionary pussy.
    >



    Now we all know our lack of qualifications.
    Wow your comments are stinging.

    --
    Peter
    PeterN, Nov 22, 2011
    #18
  19. RichA

    PeterN Guest

    On 11/22/2011 4:12 PM, Eric Stevens wrote:
    > On Tue, 22 Nov 2011 05:51:33 -0500, PeterN
    > <> wrote:
    >
    >> On 11/22/2011 3:25 AM, Eric Stevens wrote:
    >>> On Mon, 21 Nov 2011 21:30:24 -0600, Rich<> wrote:

    >> <snip>>
    >>
    >>>>
    >>>> The fact they don't turn as smoothly when you allow the weight of a lens
    >>>> to press down pretty much proves it. But feel free to experiment.
    >>>
    >>> It doesn't prove that "focusing rings are not meant to have unequal
    >>> pressure applied to them". All it does is prove that frictional forces
    >>> increase when you increase the forces applied to the focusing ring;
    >>> but I would expect that. It says nothing at all about whether or not
    >>> the focusing ring is designed to withstand any particular system of
    >>> forces.
    >>>
    >>> Regards,
    >>>
    >>> Eric Stevens

    >>
    >> Eric, I'm sure you realize you are contradicting the opinion of the
    >> world's pre=eminent optical design engineer. It can tell you what's
    >> wrong with any product, just by looking at a photo, or someone else's
    >> description.

    >
    >
    > I will go along with you as far as " ... contradicting the opinion".
    >
    > Regards,
    >
    > Eric Stevens


    On reflection, I take that back. One must be able to analyze to form an
    opinion, right or wrong. It takes no analysis to through meaningless
    crap around.

    --
    Peter
    PeterN, Nov 23, 2011
    #19
  20. RichA

    RichA Guest

    On Nov 22, 7:03 pm, PeterN <> wrote:
    > On 11/22/2011 4:12 PM, Eric Stevens wrote:
    >
    >
    >
    >
    >
    >
    >
    >
    >
    > > On Tue, 22 Nov 2011 05:51:33 -0500, PeterN
    > > <>  wrote:

    >
    > >> On 11/22/2011 3:25 AM, Eric Stevens wrote:
    > >>> On Mon, 21 Nov 2011 21:30:24 -0600, Rich<>   wrote:
    > >> <snip>>

    >
    > >>>> The fact they don't turn as smoothly when you allow the weight of a lens
    > >>>> to press down pretty much proves it.  But feel free to experiment.

    >
    > >>> It doesn't prove that "focusing rings are not meant to have unequal
    > >>> pressure applied to them". All it does is prove that frictional forces
    > >>> increase when you increase the forces applied to the focusing ring;
    > >>> but I would expect that. It says nothing at all about whether or not
    > >>> the focusing ring is designed to withstand any particular system of
    > >>> forces.

    >
    > >>> Regards,

    >
    > >>> Eric Stevens

    >
    > >> Eric, I'm sure you realize you are contradicting the opinion of the
    > >> world's pre=eminent optical design engineer. It can tell you what's
    > >> wrong with any product, just by looking at a photo, or someone else's
    > >> description.

    >
    > > I will go along with you as far as " ... contradicting the opinion".

    >
    > > Regards,

    >
    > > Eric Stevens

    >
    > On reflection, I take that back. One must be able to analyze to form an
    > opinion, right or wrong. It takes no analysis to through meaningless
    > crap around.
    >
    > --
    > Peter


    Like you and the chimps with your feces?
    RichA, Nov 23, 2011
    #20
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. RichA
    Replies:
    27
    Views:
    810
    Better Info
    Jan 19, 2010
  2. RichA
    Replies:
    1
    Views:
    276
    Ray Fischer
    Feb 15, 2010
  3. RichA
    Replies:
    10
    Views:
    600
    John Turco
    Mar 29, 2010
  4. RichA
    Replies:
    8
    Views:
    427
    David Ruether
    Jan 15, 2011
  5. RichA

    OMG! Canon AF lenses, AF mode on micro 4/3rds!!!

    RichA, Jan 19, 2011, in forum: Digital Photography
    Replies:
    9
    Views:
    527
    Robert Coe
    Jan 23, 2011
Loading...

Share This Page