As others have said, an ED/apo doublet or triplet will either not benefit at all from additional filtration help or what little benefit you may have in chromatic aberration correction (perhaps more correctly "suppression") will be offset by an overall color shift either minimal or pronounced.
Where a filter like a Baader Long Pass 495 or the relatively new Baader "semi-apo" filter will help would be with a traditional achromat. The faster and larger (objective diameter) the achromat is, the more chromatic aberration it will have and the more it can potentially benefit from a filter that suppresses the chromatic aberration.
Among my herd of telescopes the ones that would benefit most from filters like the two I mention above would be my Jaegers 6" f/5 achro, my Orion ST120 f/5, my Celestron Vixen SP C102 f/9.8, my Vixen NA 140 f/5.7, and my Antares 127 mm f/9.4. The Baader 495 really cleans up and sharpens the image, but there is a decided yellow cast to the background. I just recently purchased the Baader Semi-Apo filter but I have not had the opportunity to try it yet. I will check it out the next clear opportunity we have. Supposedly it will impart a more neutral background color along with a chromatic aberration fix.
The following telescopes do not need any help in correcting chromatic aberration and either of the two filters I have are not needed with them. I may try them at least once for "grins and giggles" but I do not anticipate any benefit - Tak TOA 130, TMB SS130, AP Star12 ED, AT 111 f/7, AT 102 EDF, ES 80 triplet.
Edited by BarrySimon615, 21 March 2018 - 08:44 PM.