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
>>>
>>> ------------------------------------------------------------------------
>>>
>>>
>>> No virus found in this incoming message.
>>> Checked by AVG - http://www.avg.com
>>> Version: 8.0.175 / Virus Database: 270.9.8/1801 - Release Date: 11/20/2008
>>> 9:11 AM
>>>
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|