Anti – Alias:  Steep Dips
By default the distance used for the anti-alias filter is the input inline/xline spacing. However you can adjust the anti-alias filter using either the anti-alias factor, or the anti-alias inline/xline spacing. If either of the values for the anti-alias inline/xline spacing is specified then they will override the input inline/xline spacing.

Our experience is that using a square (inline spacing = xline
spacing) anti-alias filter gives the best results.  This means that if the inline and
xline spacing are not the same, you should use the Anti Alias Inline (Xline) Spacing parameters: aaildist, aaxldist.  These parameters should be made equal and set to a value between the actual inline/xline spacings.  For example, if inline = 50, and xline = 35, setting aalisist = aaxldist = 37.5 should give good results.  In this case, 37.5 would be used to design the anti-alias filter.  This number can of course be adjusted up or down with the same effect as adjusting aawt.

This Example is Gulf of Mexico Salt

The first image is the result of migration with competitive software.

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The second image is the result of migration with the Tsunami software.  The Tsunami migration used the same velocity model, same seismic traces, same aperture and same parameters as the competitive migration.

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Note that in the Tsunami image, the sediments are imaged right up to the salt boundary while the Competition has gaps near the salt face.

The Tsunami image also has better imaging of higher frequencies.