Hi Vesa! ----- Original Message ----- From: "Vesa Perala" <[EMAIL PROTECTED]> Sent: Friday, May 03, 2002 11:32 AM Subject: EOS-3 AF with 100-400
> I know (think) EOS-3 has better AF at f4 when the center > AF sensor is used but I'm not sure if the AF accuracy is > affected (by cross-sensor vs. vertical sensor). I would believe that it's better... but that depends on the subject naturally (vertical / horizontal...). > I called Canon service and they said it is possible to > adjust the AF (for different lenses) so I quess I need > to send the camera and lens in. Hmmm. again lens + camera combo. This is very similar to the question I posted earlier about metering problems with certain lens. That was also acknowledged by Canon. So, if AF also happens TTL and camera sends commands to the lens motor for adjusting focus (at least this is what I've been led to understand by Canon), then how can the camera be adjusted to focus with some lenses? What would then happen to AF with other lenses? If nothing, then why is that one lens affected? I would have found it much more believable if they would have said that it's a problem with the AF motor in the lens, but in the camera...? BTW, I just realized that the metering problem that 1D had with (was it) 28-70 L, might actually be in the camera IF the camera somehow would keep track of the actuall different apertures the lens has. I mean, if the lens is stopped down to f 8.0 for instance... is it then exactly 8.0 or 8.04 or 7.96 or something else. Now, if camera would know this, then... ah, but this would be stupid as when new lenses are introduced the camera would not know about them... ok, that much for my own explanation. Anybody else? > Do you have any other good advice how to check the AF > accuracy? Do many tests and average. If you do it only once or twice you might end up seeing some random AF error too... would be easier with digital EOS... Best regards, Hugo * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
