Quick disclaimer: Besides many reports I think the so called Ashen light from Venus is not something real, if it were real now on 2012 we would have seen photos of it. It's hard to believe there's a phenomena on a celestial body as prominent as Venus that is real but has never been photographed before.
Having said that.
I took a look today at Venus at maximum brightness and there was a hint of light on the dark side, this is IMO just an optical flare from the very bright venus on my lens.
I took a photo (See attached).
Do you think this can be what many people called "ashen light"?
I believe the atmosphere can play a role, today it was very cold on my city with plenty of ice crystals in the atmosphere and plenty of cirrus clouds.
I also believe the brain plays a role, we are very used to Earthshine on the moon so I think our minds try to do this with any crescent shape from a celestial body.
Take a look at the thumbnail without opening to simulate the real size of Venus thru a scope, don't you see the dark side illuminated?
