Correction of signal after High-pass RC-filter I have one question about digital correction of signal after RC filter which is high-pass.

Let me explain detail.

I have one simple signal conditioner. It has RC filter on the signal input with cut-off frequency equals 1.3 Hz. It means that after this RC filter my signal has lower amplitude from 1.3 Hz to approximately 15 Hz. After ADC I get this signal on my computer in digital form. After that I use Fourier transform.

Unfortunately, I need correct amplitude information in range 2-20Hz. So I need correct amplitude of signal in that range by digital transformations.

Can I do this? Is it normal practice?
Yes, this seems like a normal thing to do. However, note that the signal-to-noise ratio will be degraded in the 1.3 Hz to 15 Hz band. Your signal will be smaller but the quantization noise of the ADC will stay the same.