I have just discovered the digital images of parish registers on line "England, Cornwall Parish Registers, 1538-2010 on line."
In paritcular I was interested in the Cornish Parish listed by Name of the Town (with parish) Parish Registers
It was amazing to look at copies of the Tremaine register on line and turn the page and blow up the image if I couldn't make out the writing - all in the comfort of my own home. If you haven't discovered this resourse yet you should give it a go - I was able to push my Hambly/Baker back one more generation!