Hey guys,

I'm going through the same drama I did some while ago (with a sony last time)
... trying to work out the perfectly accurate film back for my new HF S21

I understand the relationship between the given sensor size and the true dimensions
as covered here: http://www.dvinfo.net/forum/canon-vixia-hv-series-hdv-camcorders/155481-hv30-focal-length.html

But how do u work this out...
1 / 2.6" is a circle with a 4:3 sensor inside it... how big is the padding between the edge of the circle and the sensor itself?

here's an example of some other sensor sized worked out...
http://giso.files.wordpress.com/2009/04/ccdsizes.gif?w=451&h=185

I hope I have explained my issue properly...

Thanks in advanced :)