Done...
Tom
2008/11/20 Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
> In re-reading my response I note that I said: "The reason you may not
> have seen the ready light come on is that you may have been doing test
> shots without film in the camera." This is not true for the ready light
> in its "ready" role. It's only true for the ready light in it's
> flashing role as a good exposure indicator. If the ready light is not
> visible in the viewfinder with a steady glow when the flash itself is
> powered on and indicating ready then something is wrong.
>
> Dr. Flash
>
>
> Chuck Norcutt wrote:
> > I suspect that he may not be fully sorted yet. I don't belong to the
> > Rangefinder forum so perhaps you or Piers might post some of this.
> >
> > First, a warning based on the poster's intent to use the T32 at 20
> > meters. Using the T32's calculator panel (on the auto/manual side of
> > the panel) you can see that, even at ISO 400, an f/2.8 lens will be
> > required to reach 20 meters. Actually, the calculator panel indicates
> > something between f/4 and f/2.8 which my manual calculations show to be
> > f/3.1. However, since most flash manufacturers generally fib by at
> > least 1/3 stop on their guide numbers (and the T32 is no exception) the
> > actual requirement at 20 meters and ISO 400 will likely be f/2.8. If
> > you don't have an f/2.8 lens that will reach the distance required then
> > a film faster than ISO 400 will be required or else accept a stop or
> > more of underexposure.
> >
> > Of course, this all assumes that the T32 is the only light source. If
> > shooting a stage production, for example, which provides moderately
> > bright ambient light a slower film and lens may be OK. It also assumes
> > that you don't have the T32 "zoom adapter" which narrows the angle of
> > view and raises the ISO 100 guide number to as high as 42 at the 135mm
> > setting. In any case, be aware that the T32 may be approaching its
> > limits here.
> >
> > Now to some questions that were posed but not answered. Yes, the OM-2sp
> > has a "flash ready" signal in the viewfinder. It's at the extreme upper
> > left of the viewfinder and is a green (or red) square with the symbol of
> > a lighting bolt in the center. The flash ready signal glows when the
> > flash is charged and blinks very rapidly for a couple of seconds after a
> > *correct* exposure had been made. If it simply goes out then there has
> > been an under or overexposure which is indicated by "under" and "over"
> > (text) indicators between the top of the shutter speed scale and the
> > flash ready signal. These may be extremely difficult to see under dark
> > conditions since they are not illuminated like the ready signal is. The
> > "over" indicator sits directly above the shutter speed scale and the
> > "under" indicator is above that. It may be possible to see them better
> > if you use the viewfinder illuminator button (right side of camera below
> > the prism) but it only stays on for 10 seconds and it's difficult to
> > coordinate that with your shot.
> >
> > If your OM-2sp has a green ready light in the viewfinder then it's the
> > original design which draws its power from the camera batteries. If the
> > ready light is red then it's a later design which draws its power from
> > the flash batteries. Olympus modified many or the original green type
> > to the red type because of complaints about excess battery drain to
> > power the ready light. Just be aware that, when the flash is powered on
> > the camera may be using more power than usual if you have the green
> > ready light. In any case, be sure to use fresh batteries and make sure
> > you are using silver oxide rather than alkaline batteries. Alkaline
> > batteries will not last very long in OM cameras such as the 2sp which do
> > not have on/off switches.
> >
> > The reason you may not have seen the ready light come on is that you may
> > have been doing test shots without film in the camera. The OM-2sp's
> > exposure system is TTL OTF (Off The Film) which means the metering
> > system reads the light reflected from the film during actual exposure.
> > If there is no film in the camera the only thing the meter sees is
> > reflection from the black pressure plate. Not much to reflect from and
> > certainly not enough to indicate a correct exposure. If you have a test
> > roll put that in the camera before doing exposure tests.
> >
> > With the camera in Program or auto mode and the T32 in use in TTL mode
> > (calculator panel turned to the blank side) or in "normal auto" mode
> > (calculator panel outward) the "auto check" light on the back of the
> > flash should blink like the ready light does to indicate a good
> > exposure. No blink, something was wrong. If the camera is in manual
> > mode and the flash is in "normal auto" mode the flash will respond to
> > its own internal sensor and flash the "auto check" light by itself
> > without camera assistance. In that case no film is required in the
> > camera to do an exposure test since the TTL flash circuitry is not
> > involved. A test flash can also be made with the test button on the
> > back of the flash. If in "normal auto" mode the "auto check" light will
> > blink if a good exposure was indicated. When the flash is in manual
> > mode the "auto check" can't be used since the flash has no indication of
> > the aperture in use.
> >
> > Dr. Flash
> >
> >
> >
> >
> >
> >
> > Tom Fenwick wrote:
> >> Nice one Piers. I like that gentleman's pictures and thought someone
> ought
> >> to sort him out!
> >> Tom
> >>
> >> 2008/11/20 Piers Hemy <piers@xxxxxxxx>
> >>
> >>> Done
> >>>
> >>> -----Original Message-----
> >>> From: Tom Fenwick [mailto:super.wide@xxxxxxxxx]
> >>> Sent: 20 November 2008 10:53
> >>> To: Olympus Camera Discussion
> >>> Subject: [OM] Flash question on RFF
> >>>
> >>> One for you lot here:
> >>> http://www.rangefinderforum.com/forums/showthread.php?threadid=66456
> >>>
> >>> Tom
> >>>
> >>>
> ------------------------------------------------------------------------
> >>>
> >>>
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> 11/20/2008 9:11 AM
> >>>
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