Al Luna shared these two pictures with the tag line: Color balancing, gravel eye to orange.
Explaining the eye colors, Brian McCormick wrote: There are only two eye colors – pearl and orange. Orange is dominant to pearl. Orange can produce pearl but pearl to pearl cannot produce orange. Bull eye is simply incomplete meiosis of the pigment near the eye, often times in such a way that it responds and reproduces like a marking. Bull eye birds are either pearl or orange under their “sunglasses”.
By way of definition, gravel is just another term used to describe the pearly eye.
Likewise a bull eye is a dark eye. When we find an equally good picture we will add it here.
Another question that was raised was yellow versus orange. Yellow is simply a type of orange, just not as intense in color.
In the past there was quite a bit of discussion about “color balancing” the eyes, but not so much anymore. It’s the author’s belief that this was a fad that was disproved and faded with time. Now it is simply a matter of aesthetics.