Canon S50 power supply
CHRIS KIDD
to a PC with the Cannon software to permit >100 time lapse photos to be
taken. Since the camera will be running for months, maybe years, I need to
power it via the mains (or big external battery). Since I cannot get hold of
the actual cannon ac power adapter I'm trying to provide a DIY version.
However, the camera battery supplies, supposedly, 7.4V. In fact, if you test
it, it is nearer 8.4V. If I connect 5x1.5V batteries (i.e. ~7.5-7.7V) the
monitor will come on with whatever the camera is pointing at, but if you try
to take a picture, it says to change the batteries. It would seem that the
supply voltage is >7.4V... - this is a pain since most commerical power
supplies are in multiples of 1.5V and 9V is probably too great!
Suggestions?
One other issue is whether I need to worry about the Li-ion thermister
connector for the camera - presumably if you don't have the Li-ion battery
it should not be critical (unless the camera senses the voltage/current...).
Thanks
Chris
Charles
"CHRIS KIDD" <c.k...@tesco.net> wrote in message
news:Ljqcl.2660$P%3....@newsfe21.ams2...
9 volts should work fine. Try a nine volt battery.
If that works, find a wall-wart that provides a leveled (voltage regulated)
9 volts.
Warning: wall-warts come in many sizes and flavors and methods of voltage
regulation.
Stephen Henning
"CHRIS KIDD" <c.k...@tesco.net> wrote:
It most likely is not the voltage but the internal resistance. Photo
applications are very sensitive to internal resistance since they tend
to not draw much power until the shutter fires, then they take a short
but large current pulse.
I would stay below 8.5 volts but look for a lower resistance source.
I think the Li-ion thermistor is only used during charging.
--
Pardon my spam deterrent; send email to rhod...@earthlink.net
Cheers, Steve Henning in Reading, PA USA - http://rhodyman.net
Chris Malcolm
> I'm going to use my old Canon S50 as a time-lapse camera. It will be attaced
> to a PC with the Cannon software to permit >100 time lapse photos to be
> taken. Since the camera will be running for months, maybe years, I need to
> power it via the mains (or big external battery). Since I cannot get hold of
> the actual cannon ac power adapter I'm trying to provide a DIY version.
> However, the camera battery supplies, supposedly, 7.4V. In fact, if you test
> it, it is nearer 8.4V. If I connect 5x1.5V batteries (i.e. ~7.5-7.7V) the
> monitor will come on with whatever the camera is pointing at, but if you try
> to take a picture, it says to change the batteries. It would seem that the
> supply voltage is >7.4V... - this is a pain since most commerical power
> supplies are in multiples of 1.5V and 9V is probably too great!
> Suggestions?
Sounds like your source has too high an internal resistance. Cameras
take a big hit of current when the shutter fires and the card is
written to, and if the internal resistance is not low the voltage
falls below acceptable levels, which produces the warning message you
saw.
--
Chris Malcolm
CHRIS KIDD
adapter for their cameras so I'll try and source one of theirs (and they
seem to be reasonably cheap too!).
Chris
"CHRIS KIDD" <c.k...@tesco.net> wrote in message
news:Ljqcl.2660$P%3....@newsfe21.ams2...
whisky-dave
> However, the camera battery supplies, supposedly, 7.4V. In fact, if you
> test it, it is nearer 8.4V. If I connect 5x1.5V batteries (i.e. ~7.5-7.7V)
> the monitor will come on with whatever the camera is pointing at, but if
> you try to take a picture, it says to change the batteries. It would seem
> that the supply voltage is >7.4V... - this is a pain since most commerical
> power supplies are in multiples of 1.5V and 9V is probably too great!
>
> Suggestions?
>
> One other issue is whether I need to worry about the Li-ion thermister
> connector for the camera - presumably if you don't have the Li-ion battery
> it should not be critical (unless the camera senses the
> voltage/current...).
I NiCd rechargable (9V) battery is 8.4V
As you say most batteries are 1.5V but NiCd are 1.2V each
and have low internal resistance.
Be careful of using plug-in power supplies their voltage is usually
higher than the labelled voltage and they could have a high ripple current.
especially the cheaper ones.
Another method would be if you had to use 1.5V cells you can 'drop'
some voltage by using standard diodes (1N4002) each diode used in series
will
drop the voltage by about 0.7V
Stephen Henning
> I'm going to use my old Canon S50 as a time-lapse camera. It will be attaced
> to a PC with the Cannon software to permit >100 time lapse photos to be
> taken. Since the camera will be running for months, maybe years, I need to
> power it via the mains (or big external battery). Since I cannot get hold of
> the actual cannon ac power adapter I'm trying to provide a DIY version.
>
> However, the camera battery supplies, supposedly, 7.4V. In fact, if you test
> it, it is nearer 8.4V. If I connect 5x1.5V batteries (i.e. ~7.5-7.7V) the
> monitor will come on with whatever the camera is pointing at, but if you try
> to take a picture, it says to change the batteries. It would seem that the
> supply voltage is >7.4V... - this is a pain since most commerical power
> supplies are in multiples of 1.5V and 9V is probably too great!
>
> Suggestions?
How about the Canon AC Adapter that is made for your camera. Lots of
places sell it. It is the CA-PS700 Adapter or ACK-700 Adapter Kit.
They sell for $35 to $65. You can find them on ebay for $10 and up.
There is a universal AC Power Adapter for $28.95 that works with your
camera at:
http://www.bluenook.com/product_detail.asp?pid=287