table 3 shows the results of the rough first accuracy assessment of the channle combinations for the ads40 and ads80 sensor systems using the als as reference data. for this assessment the entire ^hi dataset eas analyzed without removing outlier or any other processing. in the case of the ads40, the combination of nadir and backward looking cir stereopairs shows the best performance, whereas for the ads80 the nadir and backward cir and panchromatic channle perform equally.