The experimental t-value between both the methods is 0.15,
which was less than the critical t-values of 2.31 for degree of freedom
of 8, at the 95% confidence level, that mean the results obtained from
both the methods were not significant difference. Moreover, under
the same conditions, the old calibration graph that has been already
saved was used for analyzing the phosphorus content. The results
obtained from the mobile phone camera correlated well with the
spectrophotometric method (y¼1.005x0.382: r
2
¼0.996, Fig. 5B).
The results obtained from both the methods were not significant
difference, according to examination the t-test at 95% confidence
level, the experimental t-value (0.05) was less than the critical t-value
(2.31). The developed method provides various advantages, including
more convenient, simpler, faster and cheaper analysis. In addition, the
precise concentration could be immediately displayed on the screen
when analyzed the sample. Whereas, the commercial test kit usually
provides approximated values. Therefore, the colorimetric analyzer