Uploaded this picture to Birdforum a few years ago but what the heck, this is my blog. On the left is an adult Japanese Peregrine Falcon (Hayabusa - Japanese) Falco peregrinus nominate/japonicus? (Photographed at Toyano, Niigata, in October 2007) and right, an adult Australian Peregrine Falcon, Falco peregrinus macropus (female, the smaller male was following her, at the Toowoomba cemetery, May 2002 -slide film and scanned in 2002).
The Japanese falcon is generally a paler species with an 'open-cheeked' black helmet compared to the Australian species which is darker and has a much fuller helmet.
What ever the case it's nice to see both species, and love the blue skies in these pics.