Thanks chaps.
Mike it's taken a few weeks to finely tune that PST to the best of it's ability as well as getting the mosaic panes with the right amount of overlap to totally kill these gradients. The PST has a bad name for this but I'm determined to right that wrong rumour

Sure, perhaps there are dud ones that simply won't tune in but then it's up to the buyer to send the thing back if necessary..
Anyway, it's been a nice Solar journey so far! Loving it.