Confused by Base ISO w/ Auto ISO

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RichF

RichF

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In his [great] book on the Z 9, Steve wrote

Note that with Auto ISO enabled, and under most autoexposure modes, if your ISO is set higher than 64, the camera will take this ISO value into account and use it as a “soft” base ISO. It will only drop below this value when it runs out of its primary exposure controls (i.e., shutter speed or aperture) and is still facing an overexposure. Unless you have a very specific reason not to, I recommend setting this to base ISO (64) when using the Auto ISO feature of your camera.

I use both Auto ISO and regular (manually) ISO. When I switch from Auto ISO to Manual ISO and back to Auto ISO, i leave the ISO setting at what ever value I had in Manual ISO - perhaps 2,500. As I read Steve's comments, this creates a soft base ISO (of 2,500). Does this cause a problem? Should I set the ISO back to 64?
 
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That is interesting. I'm not a Nikon shooter but it would seem that if using manual with auto iso you wouldn't have an issue, but for other auto modes you should check for yourself if the camera is trying to use the iso you chose rather than trying for the lowest possible. It would make sense since the camera can't read our minds.
 
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RichF said:
In his [great] book on the Z 9, Steve wrote

Note that with Auto ISO enabled, and under most autoexposure modes, if your ISO is set higher than 64, the camera will take this ISO value into account and use it as a “soft” base ISO. It will only drop below this value when it runs out of its primary exposure controls (i.e., shutter speed or aperture) and is still facing an overexposure. Unless you have a very specific reason not to, I recommend setting this to base ISO (64) when using the Auto ISO feature of your camera.

I use both Auto ISO and regular (manually) ISO. When I switch from Auto ISO to Manual ISO and back to Auto ISO, i leave the ISO setting at what ever value I had in Manual ISO - perhaps 2,500. As I read Steve's comments, this creates a soft base ISO (of 2,500). Does this cause a problem? Should I set the ISO back to 64?
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No problem with M + Auto ISO - it's only comes into play if the camera is in aperture priority, shutter priority, or program and you're using Auto ISO.
 
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