Agree with everyone the lower ISO you can shoot the better. Especially with many of the compact cameras. Also as mentioned it depends sooo much on the camera, lenses being used and shooting situation. Also as mentioned it depends on what are you doing with the image???? If you want to do big prints or really like to crop the lower the ISO the better.
That said I shoot the Sony RX100 at 400 ISO all the time and for my needs find the noise not to be an issue. Many of the new cameras can shoot up to ISOs of 800 (or higher) and produce silky results. For WA shots this can allow you to back off the strobe power, potentially reducing backscatter, in some cases. Higher ISOs can allow for apertures that produce more DOF, or faster shutter speeds. I agree with Interceptor, take a dive to experiment with Higher ISOs and find the spot were image noise crosses the threshold of acceptable for you. You maybe surprised.
That said I shoot the Sony RX100 at 400 ISO all the time and for my needs find the noise not to be an issue. Many of the new cameras can shoot up to ISOs of 800 (or higher) and produce silky results. For WA shots this can allow you to back off the strobe power, potentially reducing backscatter, in some cases. Higher ISOs can allow for apertures that produce more DOF, or faster shutter speeds. I agree with Interceptor, take a dive to experiment with Higher ISOs and find the spot were image noise crosses the threshold of acceptable for you. You maybe surprised.
