Dog is terrified of our patio umbrella. Ideas?

I have two dogs, both are around a year old. I've had the setter since he was 8 weeks old and he is typically a very happy go lucky dog. We recently opened up our large patio umbrella for some shade since it is getting warm out and it turns out that the setter is terrified of the umbrella. Any tips for how I can help him overcome this? I have never seen him so scared. Poor fella was shaking. He can't even see it through the window. He runs and hides! The other dog is a more recent addition and is completely unbothered by the umbrella.

I know the easy thing would be to just close it up again, but I really would rather help him overcome this so he is ok with other umbrellas he may encounter in his life.