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05-26-2012, 02:17 PM   #16
philbaum's Avatar

Join Date: Oct 2007
Location: Port Townsend, Washington State, USA
Posts: 3,659
Are you sure about this?

I'm not getting the same results in AV with auto-iso.

I just happened to have a DA300 on when i tried to duplicate your results. Aperture F8,

A. with auto-iso on Slow, i'm getting 1/200s shutter, about .7 *FL

B. with auto-iso on Fast, i'm getting 1/800s shutter, about 2.7*FL

SR position doesn't matter to the above.

Am i doing something wrong or is the camera calculation more complicated than suggested?

Aperture also figures into it. 1/800s was the fastest shutter i could get out of AV with auto-iso, until i rolled it all the way open to F4. F4 now reduces my max fastest shutter to 1/640s. Thank the divinities for TAV and manual, this is too much to keep track of, IMO.

Last edited by philbaum; 05-26-2012 at 02:23 PM.
05-26-2012, 02:39 PM   #17
jeffshaddix's Avatar

Join Date: Jun 2010
Location: Albuquerque, NM
Posts: 1,371
Auto-iso also behaves differently for pre-F lenses (I.e. any lens that you have to input the focal length). It does not rely on the focal length you give it, instead slow is fixed at 1/60, normal at 1/125, and fast at 1/200. Quite lame that it doesn't use the input FL from the user.

IMO, auto iso is sub-optimal, we should just be able to set the minimum shutter speed with the front dial.
05-27-2012, 02:11 AM   #18

Join Date: Dec 2011
Posts: 1,285
Original Poster

Last edited by beholder3; 08-11-2013 at 07:30 AM. Reason: [deleted]

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