How about power = V**2 / R ?
The voltage across the two series tubes is equal to the voltage across
a single tube but the resistance has doubled(?) The current flow would
be lower for two tubes in series ... so the resistance of each would
be also be slightly less than for a single tube?
Also the energy isn't really wasted when the extinction voltage is
reached is it? It remains in the capacitors. Do most flashes at full
power dump energy into the tube until it quits flowing or do they cut
off the flow? I remember seeing something about studio strobes color
temperature changing slightly as the voltage drops ...
-jeff
On 7/20/07, Tim Hughes <timhughes@xxxxxxxx> wrote:
>
> 2) the tubes are in series in the T28 (see schematic on Marks Website), so
> voltage acrosss each
> tube is reduced ~1/2 of single tube.
> Since the capacitor does not discharge to zero but to the extinction voltage
> of the tube (volt =
> ~60V) then with two tubes in series there is quite a bit more energy left in
> the capacitor (volt=
> ~120V) after flash completes. (a factor of 2^2 - 1 = 3x more wasted) This is
> increased wasted
> energy, unsued at end of flash.
>
> Tim Hughes
>
>
> --- Jeff Keller <jeffreyrkeller@xxxxxxxxx> wrote:
>
> >
> > The guide number is limited by the energy stored in the capacitors and
> > the width of field illuminated. If two heads are sharing the same
> > energy it seems reasonable that the guide no. would go down ...
> > -jeff
> >
> > On 7/19/07, usher99@xxxxxxx <usher99@xxxxxxx> wrote:
> > >
> > > Piers,
> > > Thanks again for these.?
> > >
> > > Weird that on the Alan Wood site in one place near where he mentions the
> > > calculator panels
> > (T28), the? GN with one flash is listed as 22 and 28 with 2 heads.? It is
> > the opposite later on
> > his site and anywhere else, including on your panel pdf.?? Must be a
> > mistake on the AW site.? I
> > don't know how the GN would go down with 2 heads (must be the case), unless
> > the controller T
> > power control attenuates the power to both.? Perhaps there is something
> > weird about GN's at
> > macro distances.? Manual macro flash shouldn't be as weird as quantum
> > effects, though Heisenberg
> > seems to lurk over my shoulder when I try it.
> > >
> > > http://www.alanwood.net/photography/olympus/t28-macro-twin-flash.html
> > >
> > > Mike
> >
> > ==============================================
> > List usage info: http://www.zuikoholic.com
> > List nannies: olympusadmin@xxxxxxxxxx
> > ==============================================
> >
>
>
> ==============================================
> List usage info: http://www.zuikoholic.com
> List nannies: olympusadmin@xxxxxxxxxx
> ==============================================
>
==============================================
List usage info: http://www.zuikoholic.com
List nannies: olympusadmin@xxxxxxxxxx
==============================================
|