Obscure light-shadow relationships in UFO photos?

[UFOphotos]

I have been taking photos of the sky and clouds and such since 2009 and sometimes I catch something I can´t explain at all. It has something to do with light and shadow and how light reflects on an object's surface. For example, you expect a reflection of sunlight but only see a shadow?

Denmark 2017:





Taken from High-altitude UFO with strange elevations

Denmark 2009:





Taken from Vertical UFO causing the displacement of sunlight

There can be many strange things in a UFO photo, but this light-shadow interaction with sunlight is weird. How can an object be dark on the side pointing towards the sun? Where is the reflection?

Is there something I've missed here?