Hi Bill, Thanks for your posting - seems like you've covered this quite thoroughly!
M Stewart Milton Keynes, UK ----- Original Message ----- From: Neukranz, Bill <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, January 11, 2002 1:02 AM Subject: RE: EOS RE: Flash meters with ETTL > OK, I did test whether or not an ST-E2 can affect a light meter. My > conclusion is, yes, it does. > > I measure the GN of an ST-E2 at approximately 3.2 (feet) at ISO 100, over a > range of 0 to 9 feet. The light meter does not respond to ST-E2 IR signals > beyond about 9 feet. > > My light meter is a Minolta Flash Meter V. My ST-E2 is mounted on a D30. > My measurements were performed during actual shutter releases (versus simply > pressing the ST-E2 'test' button). > > The light meter is not sensitive to the IR autofocus signals from the ST-E2, > only the communication IR signals that the ST-E2 emits right at shutter > release time. > snip > > I then averaged the two readings to equal 3.2 GN (feet) at 100 ISO. > > In summary, I conclude that an ST-E2 is equivalent to about a 3 GN (feet, > 100 ISO) flash unit, up to about 9', with respect to influence on a light > meter. Now I know why an optical slave plugged into a flash unit will get > prematurely tripped when in the vicinity of an ST-E2. > > Best regards, > > Bill Neukranz > > -----Original Message----- > From: Neukranz, Bill > Sent: Thursday, January 10, 2002 10:48 AM > Subject: RE: EOS RE: Flash meters with ETTL > > I hadn't ever thought about the Minolta flash meter being fooled by the > ST-E2 (mounted on-camera) infrared signals. But since an optical slave > (plugged into my non-550EX flash unit) can be fooled by line-of-sight ST-E2 > IR signals, then I conclude it's possible the flash meter might be affected > too. That's a good thought, and I'll test it. * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
