Percentile Composite of Collection in Google Earth Engine

Question

I know how to find percentiles within a single image, but is there a way that I can make an output image that is a percentile composite of an entire collection? E.g. a composite image where each pixel value is the 90th percentile value at its respective location given an input collection.

Answer 1

Try this:

//import sentinel image
var Sent = ee.ImageCollection('COPERNICUS/S2')
    .filterBounds(geometry)
    .filterDate('2020-05-01', '2020-10-30');

//calculate 90 percentile    
var Sent2 = Sent.reduce(ee.Reducer.percentile([90])));