[bioch]

I understand that the beer lamert law states: A=ecl, and that the spectrophotometer measures the transmitted light and so therefore using a lower concentration would give a larger transmission of light and give lower error.

How do you find the optimum dilution of a stock solution in order to give an absorbance of low error?

Q. by what factor would you dilute 1mmol/dm^3 solution of NADH (e= 6.22 x 10^6 cm^2mol-1) to measure its absorbance accurately.

Q. how can the beer lambert law be used to determine the optimum condition for the most accurate absorbance

[Arkcon]

I understand that the beer lamert law states: A=ecl, and that the spectrophotometer measures the transmitted light and so therefore using a lower concentration would give a larger transmission of light and give lower error.

Really?  You don't foresee any problem with vanishingly low concentrations?

[Corribus]

Moreover, error is determined largely by the instrument itself.

[JGK]

Most "official" methods set the wouking range of the spectrophotometer between 0.2 - 0.8 AU.

[marquis]

One other issue to consider is dilution error.  Often, large dilutions are needed.
The multiple dilutions can be a source of considerable error, also.

Good luck.