Can I reduce quantization error of an 8-bit digitizer?

[VI_Joe]

I use PXI-5102 & PXI-5114, both of which are 8-bit digitizers.  Is there any way to reduce the effects of quantization on a sampled signal?  Neither digitizer incorporates dithering.  I have used a digital software filter on the digitized data before, but is that cheating?  I can't afford to replace with 12-bit digitizers.  Can anyone provide advice?

Thanks in advance.

[DFGray]

Looking at the specs of both these digitizers, the input amplifiers have a half LSB random noise or worse, so averaging should work well to reduce quantization noise.  They have no option to turn dithering on and off because it is always on.

Be aware that averaging will get you better resolution, but will not overcome other systemic issues like distortion, many of which are frequency dependent.  However, most of these issues can be calibrated and compensated for a particular device, if you really need to do it.  That is a very complex subject, however...