Re: Boycott Panasonic cameras - forced proprietary battery use infirmware

Discussion in 'Panasonic Lumix' started by ray, Jun 21, 2009.

  1. Some GPS units don't freeze co-ordinates when losing signal, they
    simply keep on trucking at the last calculated speed and direction for
    a while, usually about 30 secs. So if you move into a place without
    signal at constant speed and direction you can get a good fix for up
    to 30 seconds. So you could for example walk into a church and
    steadily straight ahead until you're right under the steeple, and get
    a fix on it. And good GPS systems will let you define a waypoint as
    the average between two others, so you can stand either side of the
    church and average the steeple location. Some GPS systems with
    magnetic orientation sensors will let you take bearings on a location
    from two known positions so you can triangulate its position.

    Note that sometimes you want to locate the camera position, and
    sometimes you want to locate the image location, such as a photograph
    of a building or a distant landmark.

    If I'm using GPS to locate my photographs I like to have those kinds
    of facilities, but I don't see camera makers putting all that into a
    camera, or camera users having the patience to learn how to use
    it. Mostly they don't even read the photography section of the camera
    manual :)

    So I'm a fan of a separate sophisticated GPS unit, and simply taking a
    snapshot of it to locate a photograph.
     
    Chris Malcolm, Jun 25, 2009
    #21
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  2. Depends which model of Vista. The second model had a much improved
    receiver. Performance under tree cover also depends a lot on how you
    use. The first easiest way to improve under trees performance is to
    stop at least every half hour for a few minutes in a place with a nice
    open view, and put the GPS down, away from your body, in best
    reception orientation position (with Vistas that's horizonal face up)
    well away from your body's satellite signal shadow. That let's the
    unit acquire any new risen satellites, which it can't do when you're
    moving under trees due to the constant interruption of satellite view.
    But it tolerates constant interruption of locked satellite view.

    And of course when walking under tree canopy give your Vista the best
    view of the sky. That means don't put it in a body-shadowed pocket, clip
    it horizontal facing up to your rucksack strap on top of your
    shoulder.
     
    Chris Malcolm, Jun 25, 2009
    #22
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  3. For continuous tracking a GPS needs several acquired satellites and
    glimpses of a few roughly every thirty secs. For satellite acquisition
    it needs at least thirty secs of uninterrupted view. So a GPS with a
    good handful of acquired satellites can keep tracking in very dense
    forest, but only for a while, because if you keep moving it can't
    acquire any risen new ones to replace those which have set. And if
    it's a dense forest even if you stop it can never acquire enough new
    ones in the small windows accidentally available at a random stop.

    But switch to manual acquistion mode and you can always acquire
    satellites and keep tracking in dense woods :)
     
    Chris Malcolm, Jun 25, 2009
    #23
  4.  
    Chris Malcolm, Jun 25, 2009
    #24
  5. Let me guess. Does it do it by requiring you to leave the unit on long
    enough to acquire and lock enough satellites for a location fix, and
    then post processing can backtrack from there to the very first
    position data at first switch on from the then unidentified (and
    unparameterised) satellites?
     
    Chris Malcolm, Jun 25, 2009
    #25
  6. It's very difficult if you don't understand how to use a GPS under
    canopy. It's much easier if you do. Many of those who rely on GPS in
    heavily wooded places have taken the trouble to find out how to best
    use them under tree cover.
     
    Chris Malcolm, Jun 25, 2009
    #26
  7. ray

    J. Clarke Guest

    I'm not sure how it does it, perhaps it has INS supplementing the GPS, but I
    noticed the other day that my Garmin Street Pilot 2610 was tracking turns in
    the bottom level of a reinforced parking garage with 5 floors of parked cars
    above it and no sky visible at all
     
    J. Clarke, Jun 25, 2009
    #27
  8. ray

    Guest Guest

    very accurately. it was exactly where i expected it to be, i.e., inset
    from the street.

    even more impressive, when it got a fix inside the steel framed store,
    it was also about the right distance from the road, given where i was
    inside the store.
     
    Guest, Jun 25, 2009
    #28
  9. ray

    Guest Guest

    not necessarily.
    gps battery drain is minimal compared to other camera functions and
    assuming the gps obtained a fix, perhaps in the morning of a photo
    shoot, the time to reacquire a fix a few minutes later is near-instant.
    plus, there's at least one camera gps device that doesn't need to get a
    fix at all. it *is* instant.
     
    Guest, Jun 25, 2009
    #29
  10. ray

    Guest Guest

    nonsense. it's called a hot start and takes a second or two, tops with
    any recent gps device. older ones might be 5-10 seconds. and that's
    with multiple satellites and very high location accuracy.
     
    Guest, Jun 25, 2009
    #30
  11. ray

    Guest Guest

    assuming that's true, 8-16 hours is still a long time. how often do
    you go on 16 hour photoshoots?
     
    Guest, Jun 25, 2009
    #31
  12. ray

    Guest Guest

    you don't leave the camera on for 48 hours straight. i've gone much
    longer on a single charge, in both my gps and my slr.
     
    Guest, Jun 25, 2009
    #32
  13. ray

    Guest Guest

    <http://www.gpsmagazine.com/2008/08/garmin_announces_7_new_nuvi_gp.php>

    Garmin is also touting a new feature called "Garmin HotFix", which
    sounds exactly like SiRF's InstantFix, a feature that improves start-up
    time and lets the GPS almost instantly determine your location
    (provided the GPS has been turned on within the past 7 days).


    <http://www.patentstorm.us/patents/7466265/description.html>

    The 1-second hot start mode requires that the drift of the real time
    clock be within 0.5 milliseconds, and time accurate to millisecond can
    be correctly estimated without needing to go through data bit and frame
    synchronization to extract precise time information. As a result, the
    GPS receiver can immediately achieve position fix upon locking onto at
    least 4 GPS satellite signals.


    <http://www.buygpsnow.com/globalsat-bt-359w-globalsat-359-globalsat-gps-
    615.asp>

    Hot start 1 sec., average
    Warm start 38 sec., average
    Cold start 42 sec., average
    Reacquisition 0.1 sec. average


    <http://www.sparkfun.com/commerce/product_info.php?products_id=465>

    20 Channel EM-406A SiRF III Receiver with Antenna

    * Hot Start : 1s
    * Warm Start : 38s
    * Cold Start : 42s
     
    Guest, Jun 25, 2009
    #33
  14. ray

    Guest Guest

    nope. turn it on in the morning prior to beginning shooting photos. if
    it had a fix the day before it should only take 30 seconds to get a
    fix, often less (at least that's my experience).
    doesn't matter since that's not a real world usage scenario. people
    will turn off the device during that time.
     
    Guest, Jun 25, 2009
    #34
  15. ray

    Guest Guest

    a hot start is not a guess. it's a lock, with multiple satellites and a
    small error circle.
     
    Guest, Jun 25, 2009
    #35
  16. ray

    Guest Guest

    nope right back. it very definitely is a full gps lock.
    that's because you're wrong.
     
    Guest, Jun 25, 2009
    #36
  17. ray

    Guest Guest

    Guest, Jun 25, 2009
    #37
  18. ray

    Guest Guest

    good luck on that. :)
     
    Guest, Jun 25, 2009
    #38
  19. I keep asking you what the actual phone location system you have in
    your hand does, and how well, and you persist in replying with general
    specifications of what it might be able to do if everything possible
    had been implemented, which may not be the case with whatever you
    have. Is what your phone actually does compared to what some other
    phone somewhere else might be able to do so embarrassing?
     
    Chris Malcolm, Jun 26, 2009
    #39
  20.  
    Chris Malcolm, Jun 26, 2009
    #40
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