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Why one of the 3 clipped Landsat images does not completely overlap with 2 others in ArcMap?

Question asked by MohammadRedowan on Oct 3, 2017
Latest reply on Oct 4, 2017 by jayanta.poddar

I am working with 3 time-series Landsat data for forest attributes (cover, biomass etc). The whole scene (185 x 185 km) images overlap in ArcMap display completely. However, when I subset/clip the images to my study site using a polygon, one of three images does not overlap with other two. It shows a bit displacement (nearly half pixel). Hence I can not go further with my analysis of forest change change.

To note, all layers/images have same datum/projection. I tried to image-to-image georegister the non-overlapping image with another image to nearly 0 rmse accuracy. However, when I clipped/extracted the study area portion again from this image with that polygon, the image again was not overlapping with the other two!

How can I get all these images spatially overlap completely?

What are the possible problems which might arise in finding forest cover and biomass change for 3 time-series years using those 3 images?