– I can’t seem to add spectra to the library as Transmittance spectra – only absorbance. I have tried to create a new library where you can select transmission in a drop down menu but then when you add transmittance spectra it flips it back to absorbance.

Question

Microlab FTIR software– I can’t seem to add spectra to the library as Transmittance spectra – only absorbance.

I have tried to create a new library where you can select transmission in a drop down menu but then when you add transmittance spectra it flips it back to absorbance.

Any ideas? We need the Library as transmission spectra as that is how we’ve set up our SOP’s and our acquisition methods.

Mike Picollelli · Accepted Answer

Hello wakefield: I apologize for the late response. All library searching is done in absorbance because absorbance is linear. The Microlab PC software stores all library spectra in absorbance. When a transmission spectrum is searched, the library search is done in absorbance and presented in transmission.