Spectral redshift is currently understood to be of a variety of sources, velocity / doppler redshift, gravitational redshift, cosmological redshift, etc. Is there any ability to tell,purely from the spectral analysis of the light itself, without knowing what the source of the light is, what type of redshift one is looking at. In other words are there variations in the spectral shift characteristics of gravitational redshift -vs- doppler redshift etc. In other words if a series of light sources were made available, without the analyst knowing what the sources were, would the be able to tell or must they know the source as part of the process of discerning what type of redshift they are dealing with. Thanks.