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Abstract. Recent studies have shown that organic aerosol (OA) could have a nontrivialrole in atmospheric light absorption at shorter visible wavelengths. Goodestimates of OA light absorption are therefore necessary to better estimateradiative forcing due to these aerosols in climate models. One of the commontechniques used to measure OA light absorption is the solvent extractiontechnique from filter samples which involves the use of a spectrophotometerto measure bulk absorbance by the solvent-soluble organic fraction ofparticulate matter. Measured solvent-phase absorbance is subsequentlyconverted to particle-phase absorption coefficient using scaling factors.The conventional view is to apply a correction factor of 2 to absorptioncoefficients obtained from solvent-extracted OA based on Mie calculations.The appropriate scaling factors are a function of biases due to incompleteextraction of organic carbon (OC) by solvents and size-dependent absorption properties of OA.The range for these biases along with their potential dependence on burnconditions is an unexplored area of research. Here, we performed a comprehensive laboratory study involving three solvents(water, methanol, and acetone) to investigate the bias in absorptioncoefficients obtained from solvent-extraction-based photometry techniques ascompared to in situ particle-phase absorption for freshly emitted OA frombiomass burning. We correlated the bias with OC∕TC (total carbon) mass ratio and singlescattering albedo (SSA) and observed that the conventionally used correctionfactor of 2 for water and methanol-extracted OA might not be extensible toall systems, and we suggest caution while using such correction factors toestimate particle-phase OA absorption coefficients. Furthermore, a linearcorrelation between SSA and the OC∕TC ratio was also established. Finally, fromthe spectroscopic data, we analyzed the differences in absorptionÅngström exponents (AÅE) obtained from solution- andparticulate-phase measurements. We noted that AÅE fromsolvent-phase measurements could deviate significantly from their OAcounterparts.