When I select the TAv mode on my K20D, rather than float, the ISO blinks at a set rate (200 or 400 based on the D-Range setting). Adjustment of the shutter speed and/or aperture has no effect. Am I missing some internal setting somewhere?

[gtis]

Hi
You might have to set it to auto ISO
Neil

[enoeske]

When I select the TAv mode on my K20D, rather than float, the ISO blinks at a set rate (200 or 400 based on the D-Range setting). Adjustment of the shutter speed and/or aperture has no effect. Am I missing some internal setting somewhere?

In TAv mode, you control the Aperture and Shutter speed and the camera adjusts the ISO to get a "correct" exposure. When a setting blinks, like your ISO, it means that the "correct" exposure is not possible with the current settings. In your circumstance, the ISO wants to go lower to get a correct exposure, but it can't (due to D-Range stuff), so it blinks to tell you it can't get the "correct" exposure. The situation is too bright for ISO 200 or 400. This is usually due to setting the aperture wide open, for instance, using f/1.8 on the 50mm f/1.8 lens, or using a long shutter speed, like 1 second or longer. There just is too much light coming in with those chosen A and T settings.

[DeadJohn]

TAv blinking at low ISO means that the ISO is as low as it can go (for the current dynamic range settings and other menu items) but there's still too much light. Try faster shutter speed, narrower aperture, or as a last resort neutral density filter.

When TAv blinks at high ISO, it means there's not enough light available and the image will be too dark. Slow the shutter or open the aperture.

[aleonx3]

The blinking while TAv mode indicates the auto-ISO range is not able to accommodate the shutter-speed value set in order to obtain proper exposure. It happens quite often when you use TAv mode in broad daylight while keeping shutter speed low (often below 1/200). In which case, use Av mode with auto-ISO instead.

[jpzk]

I have been using TAv for years and I have the ISO set up in "auto ISO" ... takes care of things.
Careful not to go crazy in substandard light conditions though ...

[enoeske]

I have been using TAv for years and I have the ISO set up in "auto ISO" ... takes care of things.
Careful not to go crazy in substandard light conditions though ...

ISO is set to auto automatically when in TAv mode. Thats the purpose of that mode.

[mee]

ISO is set to auto automatically when in TAv mode. Thats the purpose of that mode.

On my K-5 II, the Auto ISO range is limitable. For instance, I have mine set to a range of 80-800

It will blink if it needs more than 800 but not go beyond my prescribed limits.

[jpzk]

ISO is set to auto automatically when in TAv mode. Thats the purpose of that mode.

Well, I meant that but goofed when I said "I set to auto ISO ..." right you are: it is the way it works.