TAv mode — do you use it?

Yes, its very useful for indoor shots where you need both variables pinned down.   Because it reduces 2 of the 3 degrees of freedom the exposure program has, you are limiting the camera to 1/3 stops + / - so it can over / under expose a bit.   I tend to hedge this by shooting RAW+ ( because I'm lazy ) and under exposing by 1/3 stop if I see it going that route.   I can fix underexposed shots easier than blown highlights.

But to be honest. with the K-5's high ISO performance, I also use shutter priority, and let the camera ramp up the ISO's.   Kids at a birthday party, for example, jacked up on cake, gummy worms, and frosting, require a predictably high shutter, so I'll rig it for "kids bouncing off walls" mode that way.

You end up with a similar end result, but giving the camera more latitude to play aperture and ISO against each other can give better exposure solutions, IMO.

I find it useful and use it occasionally.

-- Bob
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