FOV was set to default to 0x0 to force astrometry.net to blind solve and measure the effective FOV.

However, sometimes this not only takes a very long time but also fails. A better method is used now whereas we start with calculated FOV like before.
But now we stretch the image scale boundaries by 30% instead of the default 5%. This way we allow for more flexibility in finding the effective FOV while not
resorting to a fully blind solve. Once the actual FOV is measured, it is saved and the image scale tolerance is restored to 5% to help expedite subsequent solves.