This paper studies the effects of FIR filtering and introduces an adaptive FIR filtering technique designed specifically to smooth one and two dimensional accumulated flowcytometric particles through frequency histograms. The adaptive smoothing technique illustrated here will be shown to be particularly useful in compensating the uneven histogram accumulation effects which take place when data is accumulated at the lower histogram channels versus the higher histogram channels. Linear smoothing techniques will not compensate for this phenomenon which is inherent to all histograms of accumulated data. In this view, a thorough analysis is provided to deal with the dilemmas imposed by the uneven accumulation of data within these kistograms.