A dSLR's fastest shutter-speed is really no faster than its flash-sync speed.

Ah .. you again, the guy going by "SockPuppet".

 

SelfImportantName == EdBancroft?

Sock puppets? A little Free Agent for SelfImportantName and Outlook Express
for EdBancroft and you have a nifty sockpuppet conversation going here ;-)

 

Very few people are clamoring for AA powered cameras. As was pointed
out, the NiMH proponents repeatedly misrepresent the facts, and I don't
think anyone pays much attention to them.

Hey, the original Prius used 240 consumer sized NiMH D cells in series
to achieve 288 volts. You're not all that far off. I wonder if the same
people that make up these ridiculous stories about NiMH batteries in
cameras were upset when Toyota moved from D cells to proprietary NiMH
modules. True the D cells they used were not button top, but solder-tab,
so they would be harder to replace, but you can buy solder-tab NiMH
cells without too much difficulty.

 

Many photographers use the shutter curtain for effect in their photography and
it is a useful tool. With a flash, it can be used for interesting blurring
and ghosting effects and it can also be used to enhance the background
exposure in lower light. It just depends upon the curtain sync and your
ability to utilize it.

Photography is NOT about recording reality [necessarily], it is about creating
art. For some people, like a photojournalist, that may not be true, but for
most, it is about art.

Without the mechanical shutter, you simply don't have this tool as an option
for artistic creativity.

I am sorry you feel so antogonistic about it.

 

I wonder why the D-SLR makers can't include both electronic and
mechanical shutters. Nikon did it on the D70s.

 

Wrong. That's just what the USB spec. assumes will be the
minimum. But there are USB ports that provide less. And you have
yet to back up your claim that most USB ports provide 1000mA. If
that was the case, there would be no need for USB devices, such as
Energizer's charger to drop down from drawing 500ma to only 100ma
when it has to share the USB with other devices. If every USB
socket is attached to a unique USB port, there would be no problem.
But that's not the case, and though you many not be able to tell by
looking at the connectors, they may be daisy-chained, sharing power
and bandwidth. Do you really think that a low powered USB mouse or
USB keyboard would need a dedicated USB port capable of providing at
least 500mA to only that one device?

Chargers don't have small, temporary surges. They operate for
many hours, drawing current at a very uniform rate. If it was
otherwise, the faster charging Energizer USB charger wouldn't be
limited to being able to charge only two AA cells, and the Ultralast
charger that can charge up to 4 AA cells wouldn't charge so much
more slowly. Its charge rate, however, is still unknown. You only
speculated that it is slow, adding that the package provided few
details.

No need to foam at the mouth, dog. What you called a data sheet
is NOT the data sheet for Energizer's charger. It's the Duo
Charger's manual, printed in English, French and Spanish. What I
stated was copied from the Product Datasheet (CHUSB.PDF), which I'll
paste below, again, since you didn't have the decency to quote it.
It was downloaded within the last 24 hours, so you can still
download it, and you have once more been proven to be a hot air
blowhard, since what I posted has *not* been withdrawn by Energizer,
nor was any part of it fabricated. Fabrication and wild speculation
remain your specialties, not mine.

You've also posted more of your bogus nonsense with the assumption
that the problem is in any way related to USB 1.1 ports or hubs.
Nowhere does Energizer have any caveats about using USB 1.1 vs USB
2.0, it only states that their charger can drop to a very slow
charge rate if other USB devices are used. Is Energizer fabricating
a non-existent possibility? Here's my quote, that you referred to :

To provide greater context, here's the more complete quote, again,
copied from the Duo Charger (CHUSB) Product Datasheet :

Your posts often contain some minor pieces of misinformation or
deception, but this post of yours went *way* beyond merely pathetic.

You? Humble? <g>

(I couldn't honestly type "Don't make me laugh.")

 

If you don't see that I continued it in a humorous vein (and I
replied to Allen's post, which really didn't add any humor, not to
yours), you need to re-examine what I wrote. I could have added
much about using NiMH vs Li-Ion batteries, but recognized that it
wasn't really appropriate. But I see that in SMS's reply to your
message he's added his usual loony speculation, so I'll correct at
least part of it, as well as something that you wrote :

It doesn't make sense to want to use AA powered digital cameras?
That was true several years (by now "many" years?), when AA powered
cameras were often unable to take more than several dozen shots,
sometimes as few as 10. For at least three years it has been
possible to buy cameras that are able to take *many* shots using
regular alkaline AA or NiMH batteries. The first set of alkaline AA
batteries used in my 2004 Fuji S5100 was good for well over 600
shots, more than 100 taken using the flash at full power. Using
NiMH batteries it's now possible to take well over 1,000 shots per
charge. Many Canon cameras do even better, getting up to 1,600
shots per charge. This makes cameras using AA batteries much more
capable now than they were years ago, and it would be quite
inaccurate to say that they make little sense except for people that
don't use their cameras much, or if used only as an "accident"
camera. Several people have posted messages in the last year or two
praising their Canon A610/A620 type cameras. Several of them noted
that they'd taken up to several hundred pictures over periods
ranging from 3 to 6 months, all on the first set of batteries. It's
not exactly *heavy* use, but neither is it *light* use, and it is
typical of many how many photographers use their cameras.

If you're one of those that clamor for Li-Ion batteries, that's
fine too. But you should realize that when evaluating batteries to
find out which types are the most convenient or the cheapest to use,
no one type always wins out. Much more depends these days on how
the cameras are used than on which types of batteries are used, and
you might be surprised by which types of batteries win out, and
under which conditions. As even the most expensive battery types
these days are quite affordable, most people don't care, making
their sometimes unreasonable biases easier to remain intact.

This is one of the stupidest statements SMS has ever made. He
supposedly knows all about batteries, used not only in consumer
products, but in heavy duty industrial products as well. If he
wasn't trying to back up his usual bogus points, he would have
recalled that solder tab (and welded tab) cells are NOT used to make
replacement more difficult. They're used to make their use more
reliable. Button top cells have relatively high contact resistance,
and it increases over time, due to the effects of oxidations and
grime. When used at the especially high currents demanded by
electrical auto engines, they would waste more battery power and
produce more heat at the contact points and make for less reliable
operation. The addition of the contact springs alone, needed for
240 button top D cells would also waste space, requiring the use of
a larger battery compartment.

This is no different in NiCD, NiMH and Li-Ion battery packs that
use multiple cells for powering portable phones, cell phones, PDAs
and laptops. They don't use button top batteries and spring metal
contacts. They use cells that have been connected using soldered or
welded tabs because it makes the battery packs more reliable. Almost
all portable phones and cell phones use battery packs that can be
easily replaced in seconds without using tools. Portable phone
battery packs tend to be very inexpensive, but cell phone battery
packs are usually far more expensive, but still easy to replace.

I'm sure that the SMSpinmeister knows all of this, but when did
facts ever get between him and the bogus points he tries to use to
mislead the gullible?

 

bullshit.

from the official usb spec,
<http://www.usb.org/developers/docs/usb_20_040907.zip>

table 7-7 in section 7.3.2 (page 178) shows a *maximum* of 500ma per
port.

furthermore, a device is initially only guaranteed 100ma and must
request 500ma from the host.

kindly cease your disinformation campaign.

 

Read page 171 of the USB 2.0 spec, section 7.2.1 under "Classes of
Devices," that specifies when a low-power port is permitted.

You cannot have a low power port on a computer, except under one
condition specified in 7.2.1., a condition that is only ever taken
advantage of in extremely small systems such as PDAs and UPCs. You _can_
have a low power port on a bus-powered hub, and the available power per
port is 100mA.

Technically, it might be legal for a notebook manufacturer to detect
when on battery power, and then reduce the available current to that of
a low-power port, and only supply the higher current when on external
power, but this is never done in practice as it would add a great deal
of expense and complexity to the system, and lead to all sorts of
technical issues when switching from external to battery power on-the-fly.

You're reading table 7.7 incorrectly. Under "Supply Current" you're
guaranteed a minimum of 500mA out of the hub, and the device (function)
is supposed to draw a maximum of 500mA. In reality, the supply current
is always somewhat greater than the 500mA minimum, and while it isn't
really kosher to design a device that draws more than 500mA, many
devices will take advantage of the higher current if available. They get
around this apparent violation by supplying an external wall adapter to
use if the USB port current is insufficient.

Maybe Eveready was worried about someone plugging the Duo charger into a
Bus Powered hub, so they put in that warning about charge current.

Unfortunately they should have been more verbose as their wording
apparently led some non-technical people to believe that plugging in
multiple devices to their computer's USB ports will reduce the current
on each port, which is completely false. Instead, they should have
instructed users to only plug the device into a powered hub, or directly
into the computer's USB port. At least this would not have confused
people and led to all sorts of wild assumptions as to how USB power works.

 

Nonsense. Energizer said nothing about the possibility of
plugging the charger into a bus powered hub. They explicitly
described what could cause the charger to draw only 100mA. You've
now read the explanation from several sources, unless for some weird
reason you're now trusting my quotes to be valid instead of the
"fabrications" you earlier claimed them to be. The reason give by
Energizer was that other USB devices drawing current from the port
would be why the charger wouldn't draw the full 500mA. Once again
you've posted misleading, deceptive speculation, disguised to appear
as if it were fact. Is Energizer also mistaken, or is what they
have said also a fabrication? Just rhetorical questions, since we
know that you go to great lengths to avoid honest answers.

Riiiight. If you actually believe this, you're in really bad shape.

 

you mean this part?

7.2.1 Classes of Devices
The power source and sink requirements of different device classes
can be simplified with the introduction of the concept of a unit
load. A unit load is defined to be 100 mA. The number of unit loads
a device can draw is an absolute maximum, not an average over time.
A device may be either low-power at one unit load or high-power,
consuming up to five unit loads. All devices default to low-power.
The transition to high-power is under software control. It is the
responsibility of software to ensure adequate power is available
before allowing devices to consume high-power.

or this part?

7.2.1.4 High-power Bus-powered Functions
A function is defined as being high-power if, when fully powered, it
draws over one but no more than five unit loads from the USB cable.
A high-power function requires staged switching of power. It must
first come up in a reduced power state of less than one unit load.
...
High-power functions must be capable of operating in their low-power
(one unit load) mode with an input voltage as low as 4.40 V, so that
it may be detected and enumerated even when plugged into a bus-
powered hub. They must also be capable of operating at full power
(up to five unit loads) with a VBUS voltage of 4.75 V, measured at
the upstream plug end of the cable.

maybe this?

7.2.3 Power Control During Suspend/Resume
Suspend current is a function of unit load allocation. All USB
devices initially default to low-power. Low- power devices or
high-power devices operating at low-power are limited to 500 mA of
suspend current. If the device is configured for high-power and
enabled as a remote wakeup source, it may draw up to 2.5 mA during
suspend. When computing suspend current, the current from VBUS
through the bus pull-up and pull-down resistors must be included.
Configured bus-powered hubs may also consume a maximum of 2.5 mA,
with 500 mA allocated to each available external port and the
remainder available to the hub and its internal functions. If a hub
is not configured, it is operating as a low-power device and must
limit its suspend current to 500 mA. While in the Suspend state, a
device may briefly draw more than the average current. The amplitude
of the current spike cannot exceed the device power allocation 100 mA
(or 500 mA).

wikipedia has this to say:
<http://en.wikipedia.org/wiki/USB>

The USB specification provides a 5 V (volts) supply on a single wire
from which connected USB devices may draw power. The specification
provides for no more than 5.25 V and no less than 4.35 V between the
+ve and -ve bus power lines. Initially, a device is only allowed to
draw 100 mA. It may request more current from the upstream device in
units of 100 mA up to a maximum of 500 mA.
...
Some USB devices draw more power than is permitted by the
specification for a single port. This is a common requirement of
external hard and optical disc drives and other devices with motors
or lamps. Such devices can be used with an external power supply of
adequate rating; some external hubs may, in practice, supply
sufficient power. For portable devices where external power is not
available, but not more than 1 A is required at 5 V, devices may have
connectors to allow the use of two USB cables, doubling available
power but reducing the number of USB ports available to other devices.

very few devices take more than 500ma because it is not guaranteed. in
fact, i have heard of some devices failing to work, notably bus-powered
hard drive enclosures, as well as causing port blowouts. a device
requiring more than 500ma is out of spec. if this nimh charger needs a
powered hub to supply necessary power, then the advantage of it being
usb is totally lost.

 

This part:

"Root port hubs: Are directly attached to the USB Host Controller. Hub
power is derived from the same source as the Host Controller. _Systems
that obtain operating power externally, either AC or DC, must supply at
least five unit loads to each port. Such ports are called high-power
ports._ Battery-powered systems may supply either one or five unit loads."

Every USB port on a desktop _MUST_ supply 500mA per port _minimum_.
Using all the USB ports has no effect on the 500mA per port that must be
supplied, though it can effect current _over_ 500mA because the power
protection circuit has two cutoff modes. It will cut off individual
ports at a certain level (typically 800-1000mA) but it will also cut off
_all_ the ports, if the combined current exceeds 2.0A.

What is true is that it would be _possible_ to design a laptop PC where
the maximum current per port varied based on whether the notebook was
plugged in or on batteries. You could legally reduce the USB current to
100mA per port when operating on battery power. In practice this is
_never_ done because a) it would increase the complexity and cost of the
laptop, and b) it would cause problems during operation, i.e. if an
external hard drive was in use during a power failure and suddenly
disconnected due to lack of power.

I think the Energizer was worried about someone plugging the NiMH
charger into a bus powered hub. This is the only way that additional
devices would affect the available current of other devices (at least in
terms of the 500mA minimum). Unfortunately, they didn't communicate this
very well to the technical writer.

Every hub inside a PC is a Root Port hub and supplies 500mA per port,
with no effect on the 500mA no matter how many of the ports are used.
Don't think of a hub as only an external hub. It's only an external, bus
powered hub that supplies only four units of power (one unit is used by
the hub itself, and four units are available for devices).

You're right that the devices that draw more than 500mA are out of spec.
But if they're only a few hundred mA over the limit they'll usually
work. I've never found an external notebook hard drive that wouldn't
work on a USB port without the adapter. I've had an external DVD/CD RW
drive that wouldn't work in some situations (writing) but would work
fine in some situations. If it causes a port blowout then the USB power
protection circuit is not working. Even a simply polyswitch will prevent
port blowout. What we did on the Compaq machine with the guaranteed
high-power USB port for Multibay (shown on the charger site) was to
dedicate an entire root hub to that one port.

The NiMH charger just requires a normal, 500mA USB port, as found on any
computer manufactured in the last ten years or so. This isn't rocket
science. Personally I'd like the option of a Y connector on these
chargers to increase the available current per cell, but 250mA is
sufficient for overnight charging.

 

Some P&S digicams actually do have a high flash-synch speed.
I had a Minolta Dimage 7Hi (it died at the time of the Sony 5mp sensor
recall), it's highest shutter speed was 1/4000th in Program mode and
1/2000th in Manual mode, it could flash-synch with it's pop-up flash at
these shutter speeds.
Because it had Minolta's proprietary flash shoe and no PC socket, I
never got a chance to try an external unit flash with it.
It had a mechanical iris shutter, so it didn't have separate shutter
curtains which cause a black stripe if a FP shutter is used above it's
flash-sych speed and because of the small diameter of the opening, it
could have a fairly high shutter speed.
I wouldn't call it an "ideal" camera, it had acceptable noise at ISO 100
and ISO 200 and if you're in dim lighting, a bit too noisey at ISO 400
and almost useless at ISO 800.
The 7Hi was also a OK with AF and the 4x zoom on MF did help in good
lighting; but in dim lighting it would hunt and the 4x zoom on MF just
made the red/green noise in the image easier to see.

I personaly can't see the point of "SelfImporantName"s rant, the
trade-off between ultra-high flash-synch with a pop-up flash (P&S
camera) versus low noise at high-ISO (DSLR & DRF camera) seems like a
"no-brainer" as far as I can tell, because it means that pictures can be
taken in low light without using the flash without getting an image
that's a mess of noisey pixels.

 

It's more than just low noise at high ISO. One of the biggest advantages
of the D-SLR is the lack of shutter-lag.

It's easy to live with the slower flash synch, after all, it's always
been that way with SLRs, even film SLRs.

 

SMS wrote:

High-speed flash synch (pulsed flash) totally side-steps the problem.
External flashguns that can send out a series of flash pulses to cover
the whole exposure at high shutter speed (higher than the native "flash
synch speed") has made the electronic shutter for DSLR cameras a thing
of the past.
If I remember correctly, there tended to be bit of image smearing if the
electronic shutter was used for high-speed falsh synch.
That's the only bit I can remember from the the D70s review on dpreview.com.

 

maybe. no guarantees. might blow the port (i've seen it happen).

i've seen numerous failures for the drive to spin up.

if its out of spec, anything goes.

 

Also:
1)no lag in the "live view" on the LCD or EVF that a P&S digicam usually
has.
2)very fast AF in most lighting conditions, right down to dim lighting
in which manual focusing also isn't really possible (at least what I've
found with Pentax DSLR cameras, ist-DS and K10D).
3)the choice to be able to change lenses for a faster, longer or wider
one as the situation demands.
4)I'm sure there's more, but at 11:30pm I'm starting to run out of juice
and suggestions.

Then HS/FP flashguns came around and suddenly it's possible to flash
synch all the way up to the top shutter speed with a DSLR while using
the correct accessory flashgun, if you can put up with the reduced GN
that comes with pulsed flash.

 

I wouldn't design something that depends on a USB port delivering more
than the guaranteed minimum of 500mA. The DVD/CD drives and hard drives
don't really depend on it, as they always come with either an external
power adapter, or a Y cable that lets them draw power-only from a second
USB port. However the notebook drives (at least the recent ones) seem to
always work fine from a single USB port, though I've only tried it on
Dell and Compaq notebooks/tablets, and ASUS motherboards.

The key point is that the root port hub inside the computer can deliver
a minimum of 500 mA, on each port, even with all ports being used.

It's a bizarre warning on the Energizer charger, which misleads people
that don't understand how USB works. They should have just stated, "Do
not plug this charger into a USB hub that does not have its own power
supply."

Energizer has deluded people (or perhaps only one person) into
statements like "If every USB socket is attached to a unique USB port,
there would be no problem." I don't know what he was thinking, maybe he
thinks USB is like the old 10BASE5 Ethernet or the Enhanced Parallel
Port (1284.3), rather than a multi-level star topology like USB, where
each USB socket _is_ attached to a unique USB port.

 

Of course you don't know. You're too absorbed in your delusions,
including the one where you stated that most USB ports are capable
of providing close to 1000mA.

 

dj_nme wrote:
[]

1 - the EVF of a small-sensor camera can be brighter, although the DSLR
offers finer control of framing.

3 - can cause you to loose shots - better the full-range zoom on the ZLR
than having to change between lenses. Changing lenses also introduces
dust which causes problems for the DSLR. Lenses like the 18 - 200mm VR
zoom from Nikon are perhaps better as general walking-around lenses, but
they are expensive and somewhat heavier.

"You pays your money and takes your choice".

David