Spectra program usage:
Most useful keys:
+
enlarge the curve vertically
reduce the curve vertically
Alt +
enlarge the curve horizontally
Alt reduce the curve horizontally
Page Up
next spectrum from a file
Page Down previous spectrum from a file
Ctrl - Z
reload all spectra
Esc
reload current spectra only
Removing a background :
Select a method from menu 'action > background > '
Constant: a constant value will be substracted.
Press left mouse button at one point and release it
at the other one. An average value will be calculated
and substracted. You can also select the value to substract
by clicking at desired point of a spectra.
Linear: a linear background will be substracted
Press left mouse button at one point and release it
at the other one. A line going through these two points
will be substracted.
Power: a power background will be substracted
Press left mouse button at one point and release it
at the other one. All points between these two points
will be used to approximate a power function
which will be substracted.
Shirley: secondary background will be substracted using Shirley
method
Press left mouse button at one point and release it
at the other one. Shirley algorithm will be used to find the
secondary background. If background is badly calculated it
will not be substracted.
Tougaard: secondary background will be substracted using Tougaard
method
A dialog box will appear from which you can choose
convolution
type.Later press left mouse button at one point and
release it
at the other one. Tougaard algorithm with selected
convolution
function will be used to find the background which will
be
substracted.
Additional switches:
Apply to all: if unchecked background will be substracted only from
spectrum displayed on the screen. Two more data sets will
appear :
- calculated background
- difference (oryginal data - calculated background)
You can accept change by pressing ENTER, or abort pressing
ESC.
If 'Apply to all' is checked background will be substracted
from
all spectras with no visualisation.
Step by step: if 'Apply to all' is checked you can also check 'Step
by
step' mode.Background will be substracted from spectra
one-by-one starting with the current spectra until the
last
spectra in the file.After each subtraction results will
be
visualised. The program will wait for pressing SPACE and
then
continue with next spectra. If you are tired of pressing
spacebar, you can anytime go back to the menu and uncheck
it.
During the step-by-step procedure you can scale the graph
or
change background subtraction method. You can stop the
procedure by choosing 'action > break ' from the menu.
Breaking the step - by - step procedure :
To stop the step-by-step procedure select 'action > break' from
menu
Saving information about a peak:
(i)
Select 'action > collect peak data' from menu.
(ii)
Choose a file that will be used to save the information
(iii) Press left mouse button at peak start and release it at peak
end
Data will be saved automatically.
Smoothing:
(i)
Select 'action >smoothing' from menu.
(ii) Choose a smoothing parameter. This parameter will now be used
for all spectras until you change it.
Colors:
You can adjust data sets colors by selecting 'action >colors >' and
then
Points
to set the color for oryginal data points
Line
to set the color of short vertical line at cursor
position
Background
to set the color of calculated background
Difference to set the color of difference (data - background)
Reset settings:
If you have set colors that you don't like or enlarged the curve
too much,
you can reset these values to their defaults by clicking 'action
>reset settings'.
Information:
Clicking 'action > information' will display information about
spectrum file
eg. scan information.