Blue hue on Moon, Lens or exposure?

[Sun]

I filmed the Moon and noticed a blue hue around the edge. I'm not sure what the cause is to be honest. The Lens is a cheap Phoenix 100-300mm lens and I used the 2x converter built into the GH2 and the digital zoom on 2x as well. I know the 2x digital zoom is bad for resolution but it cropped the moon enough to fill the screen which is what I needed. Is it just the lens or is this just the digital zoom? You will notice the blue edge in 1080p mode below.

 

[bitcrusher]

Thats the lens. Its called Purple Fringing. Which is another word for Chromatic aberration.

 

[mpgxsvcd]

Here is one I shot with a cheap 400mm Canon FD lens. Try to prevent the moon from over exposing. That will show more detail.

 

[Barry_Green]

Yep, that's the lens doing it. Most lenses are more susceptible to color fringing when used wide-open, you will typically get better performance when the lens is stopped down some. Even my Compact Primes will show some purple and green fringing when used at T1.5, but by 2.0 to 2.4 that disappears and they're crisp and sharp.