Chromate 4300 - Page 29

ChroMate™ ChroMate™ Operator’s Manual Doc. 4300 Rev. E 25
Point to Point (Continued):
NOTE: Assay axis types are available
under other regression modes as well.
Description:
Assay Axis Types:
Data may be entered for linear-linear, ln
(= natural log)-linear, linear-ln, or ln-ln
calculations. A logit-log calculation is also
available. Absorbance, or ln of (1000 *
absorbance), is always on the “Y” axis.
Concentration, or ln of concentration, is
always on the “X” axis.
1. “Y= ABS, X=CONC” - both the
absorbance data (y) and the
concentration data (x) are linear.
2. “Y=Ln (1000*ABS), X=Conc” - the
natural log of the absorbance is plotted
against the concentration. The
absorbance values are multiplied by 1000
before taking the logs.
3. “Y=ABS, X=Ln(Conc)” - absorbance is
plotted against the natural log of the
concentration.
4. “Y= Ln (1000*ABS), X=Ln(Conc)” -
the natural log of the absorbance is
plotted against the natural log of the
concentration.
5. Select “Y= Logit(Abs), X=
Log(Conc)” to calculate unknowns using
the equation: Abs Logit = Ln [(sample/0
cal) / 1-(sample/0 cal)]
When using the Logit calculation, the “0”
calibrator is not plotted as part of the
curve; it is used only for the calculations.
6. “Y=Log(1000*Abs), X=Conc” - the
base-10 log of the absorbance is plotted
against the concentration. The absorbance
values are multiplied by 1000 before taking
the logs.
7. “Y=Abs, X=Log(Conc)” - absorbance is
plotted against the base-10 log of the
concentration.
8. “Y=Log(1000*ABS), X=Log(Conc)” --
the base-10 log of the absorbance is plotted
against the base-10 log of the
concentration.