It might be useful to read this comparison put together by Gary Honis that shows how removal of the LP1 improves clarity/resolution:
http://dslrmodifications.com/FullSpe...lSpectrum.html
The LP1 anti-aliasing filter produces a smearing or blurring effect of the sensor surface in a non-modified camera. The reason the manufacturers include it was to eliminate the chance of moire pattern artifact appearance in photos, not usually evident in astro photos.