I am working on a project comparing each pixel every 4 years for the same AOI from Landsat Images (1986-2017). It involves with Landsat 5, 7 and 8 images. Do I need to perform image registration as image preparation? I am using only RGB and NIR bands all data has the same spatial resolution (30 m). I am using higher level data (level 2). Can somebody explain why it is necessary or not?
Using Collection 1 is not necessary:
In 2016, the USGS reorganized the Landsat archive into a tiered collection. This structure ensures that Landsat Level-1 products provide a consistent archive of known data quality to support time-series analyses and data “stacking”, while controlling continuous improvement of the archive and access to all data as they are acquired.
So use Collection 1 Level-2 scenes: