Stephen,
I don't have the 70 model, but I can offer some insight to your question on why the blurriness is worse at low light.
The focus sysmtes in these nxcam models seem to all work on a feedback look that tries to get the sharpest edges, particularly vertical edges.
When the sensors are working in low light, they have video noise. Noise is where the sensor can't quite tell which of several colors or shades it should be, so it changes between the range that it thinks it is.
The focus system sees the sensor output changing and things that it needs to adjust the focus, so it trys to do that.
This style of focus system will always be worse at low light.
John
John Lenihan
LeniCam Video Productions
http://www.lenicamvideoproductions.com
