Anti-solar Glows ~ Kevin Earp captured this scene at 5am on May 12, '11 at Willington, Bedfordshire, UK. A bright glow suffuses the crops around his shadow.  One of the huge buildings in the distance is the Cardington hangar which housed the innovative and successful R100 airship and the ill-fated R101.   ©Kevin Earp, shown with permission.

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A glow in crops directly opposite the sun might be a heiligenschein caused by dew drops or an ‘opposition effect’ glow caused by shadow hiding.      

Both can contribute. However, here it is the opposition effect that is probably dominant.

Why?    The glow is elongated along the direction of the crop stems and shadow hiding is clearly evident in the large background image.    

At the antisolar point, ASP, shadows are invisible because they are directly behind the leaf casting them.   Move the eye away from the ASP and the shadows become increasingly visible on the side of the object towards the ASP.     These progressively more visible shadows are evident around the shadow of Kevin’s head.   The dearth of shadow near the ASP makes it appear brighter.

The opposition effect glow is stretched  into a bright streak when the shadow hiders are elongated, as here.

Some of the leaves are very bright.  There ‘might’ be a contribution from morning dew focussing light backwards to form a heiligenschein.