Obstacle Avoidance Warning at 250 feet

[Warnica]

Today was a perfect fly day, Kp index of one, crystal clear blue sky, not a cloud in site.
I had calibrated IMU, gimbal, compass etc to cure a horizon tilt, didn't help but had a good flight over a flat farm field with the tallest trees a long the road, maybe 50-60 feet.
I'm flying along at 250 feet and I get the obstacle avoidance warning. I thought maybe a big bird but no bird in site. It happened only in one area and no problem anywhere else but that area of about one acre. No power lines, no towers, just farm field. Outside of that acre, no obstacle warnings.
Anyone else have obstacle warnings at 250 with nothing in the air near it?
Thank you
Bill

 

[Meta4]

Anyone else have obstacle warnings at 250 with nothing in the air near it?

Those mid-air obstacles are usually a low sun.
No-one has hit it yet.

 

[Warnica]

Those mid-air obstacles are usually a low sun.
No-one has hit it yet.

Thank you for your reply, 12 noon today and only in one area.

 

[Just_nick]

Yes, it's usually the sun.

 

[Warnica]

Yes, it's usually the sun.

Thank you. I thought with noon sun being straight over head it wouldn't hit the sensors?
But you are saying it would anyway? Never happened before but it has been awhile since we've had such a bright sunny day.