how to confine the range of colorscale in pcolor?

Hi,

I have used pcolor to make the 2-dimensional numerical data coloring in pcolor with default configuration.

But there is a very sharp peak in this data, so it looks like only one region is brightening.

I want to use pcolor with a narrower color range like i show you in the attached figure for two arrows directing.

how can i set color range only from sky-blue to yellow?

Thanks.