These days there are a number of  popular iPhone Apps (and Photoshop plug-ins) which render an image as monochrome, except for one spot of colour. Yesterday, while on a solitary photo-walk along the banks of the Don river in Toronto, I captured an image which seems to duplicate this effect; the red leaves and stems jump out from the muted shades of the background, and no post-processing was required to get this effect.

Reality is the best app there is 🙂