When I say flash auto mode I'm referring to the three non-TTL flash
controlled auto exposure modes supported by the T-32. The T-32 was not
set to "partial power" it was set to flash controlled auto mode at ISO
400 which was calling for f/8 at the camera. The T-32's slider does not
only control full and 1/4 power but also switches the three flash
controlled auto modes in and out. Since the flash thought the lens was
set at f/8 when in some shots it was set at f/11 the exposure on those
shots will be a stop short.
Dr. Flash
Steve & Alicia Goss wrote:
> Chuck-
> Not exactly sure what you mean by the T-32 not being in TTL mode versus
> auto mode. The T-32 really isn't that sophisticated. The only real
> control is the slider that controls how much power it puts out. The only
> thing that switching the panel over to "Auto" does is ensure that the
> power switch is set to full output.
>
> So if you had the T32 set to partial power, and the lens got moved to
> f11, those may be underexposed, if using all of the partial power wasn't
> enough for the situation.
>
> At least, that's my theory. The big question will be answered when the
> roll gets developed.
>
> Thanks, Steve Goss, Dallas Tx usa
>
> Chuck Norcutt wrote:
>> OK, I think I have this figured out. I finally found the reference to
>> the fixed 1/60 second shutter speed with a T-flash attached. It's in
>> the eSIF. It does not appear in the OM-2/2n or T-32 manuals.
>> Furthermore, it's specific to the OM-2n. The OM-2 does not do flash
>> ready, does not know the flash is there and doesn't force the shutter
>> speed to any specific value.
>>
>> Yes, the camera does show "flash ready" with both body and flash in
>> their respective auto modes. That should mean that the camera has
>> recognized a T-flash unit and, since the ambient light was well below
>> 1/60 second, it has set the shutter to 1/60. Since the camera is in
>> auto mode and has sensed a T-flash it will assume that the T-flash is in
>> TTL mode... it has no way of knowing that it's not. When the flash
>> fires, the camera will issue a quench signal to the flash when
>> sufficient light has been received. However, since the flash is in auto
>> and not TTL mode the flash isn't paying attention to the quench signal.
>> It will do its own thing according to the indicated ISO and aperture
>> on the calculator panel which was showing ISO 400 and f/8. Those
>> exposures taken at f/8 should be properly exposed. Those exposures
>> taken after the aperture ring was accidentally shifted to f/11 will be
>> underexposed by one stop. As Wayne indicated that's not much of an
>> error for color negative film.
>>
>> Dr. Flash
>>
>>
>> Moose wrote:
>>
>>> Chuck Norcutt wrote:
>>>
>>>> I decided to go retro at Christmas dinner tonight so took out the
>>>> pristine, black OM-2n and a T-32 and a roll of Kodak NPS 400....
>>>>
>>>> What I *think* should happen is that the camera will see the fairly low
>>>> ambient light around the dinner table and, at f/8 or f/11, despite the
>>>> ISO 400 film, will decide to use a shutter speed somewhere around 1/15
>>>> second or so.
>>>>
>>> Did you see a flash ready light in the viewfinder? If so, you should get
>>> 1/60 shutter speed. The flash ready signal is how the camera knows there
>>> is a T flash attached.
>>>
>>> The T32 manual shows the viewfinder flash confirmation light indicating
>>> flash ready and flashing to show adequate flash exposure in flash Auto
>>> mode on the OM-1n, so the flash ready indication does indeed operate in
>>> flash Auto mode. There wouldn't be any point in the OM-1n otherwise.
>>> That should cause the OM-2n in camera Auto to set a fixed 1/60.
>>>
>>> A. Flashy Moose
>>>
>
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