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Re: [OM] Hep! Dr. Flash needs... um, flash help

Subject: Re: [OM] Hep! Dr. Flash needs... um, flash help
From: Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
Date: Fri, 26 Dec 2008 07:00:38 -0500
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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