Underway optical chlorophyll-a and turbidity data were collected along the cruise track with Sea-BirdScientific ECO FLNTU sensors installed within two autonomous measurement systems, called self-cleaning monitoring boxes (SMBs). The SMBs measure alternatingly. While one box is measuring, theother one is being cleaned. The boxes switched generally every 12 hours which was reduced to 3hours for about one week during the cruise. The water inlet for the SMBs is at about 4 m below seasurface. Online monitoring of the NRT data stream revealed large offsets between the sensors andnegative chlorophyll-a values for one sensor. Consequently, the sensors in the measurementcontainers were exchanged a few times by the scientific-technical service during the research cruisefor testing purposes, including a spare sensor. Analysis of the parallel operation time of the twomeasurement boxes showed that all three sensors are highly correlated, but a significant offset wasobserved for one sensor. The chlorophyll-a and turbidity data were therefore corrected to align thesensors and obtain a consistent and non-negative time series. Chlorophyll-a and turbidity data wereboth quality-controlled before and after sensor alignment. The data were then compared tochlorophyll-a and suspended particulate matter (SPM) determined in the lab from discrete watersamples. A calibration was obtained based on comparison with the HPLC total chlorophyll-a bysplitting the time series into two different time periods based on different water masses. The timeperiod at the beginning of the cruise corresponds to the open Indian Ocean and the second timeperiod to the Bengal Shelf. Resulting calibrated chlorophyll-a matches well the HPLC chlorophyll-a.Turbidity values were compared to discrete SPM samples. The correlation between these is low,probably due to methodological sensitivity in these clear waters. A comparison with satellite datausing the GlobColour CHL1 and SPM-OC5 product is additionally provided for both parameters.Details on all quality control steps, calibration and the comparison with satellite data can be found inthe data processing report. The resulting data set contains the original data and correspondingquality flags achieved by the quality control algorithm as well as the calibrated data withcorresponding quality flag for chlorophyll-a and the corrected data through sensor alignment withcorresponding quality flag for turbidity. The data source is given through the name of the active SMB.The data set contains data during transit time and station work. We recommend to use ship's speedto filter for only transit data.