Contents - Index

Digitizer Options

There are a few options available on the Setup window in the Mass Spec Digitizer utility.  Normally you will not need to change them from the defaults.

Baseline Offset
The Baseline offset is used to establish the lowest search point for the automated digitizing process.  The default is 2 and this should seldom need to be changed, but it can be adjusted up or down if needed.  Baseline offset has no effect in Manual mode.

Filters
Filters include a Sharpen option and the Gray Filter.  Neither filter is likely to be needed very often.  Clicking Sharpen can sometimes increase the visual resolution of a low quality image to aid in manual processing.  This is only a visual effect that does not provide any benefit for Automatic processing, so it would only be used for a more legible picture if you wanted to process a particularly poor image in manual mode .  If Sharpen does not improve the appearance, you can click on Undo on the Edit menu to revert to the previous, default image.

Gray Filter can be used in some cases to eliminate interferences.  For example, if a mass spectrum was plotted on a grid pattern which is not common, it could impact automated processing.  In this case clicking on Gray Filter will screen out all gray scale pixels which will normally remove the grid.  Of course if the entire image happens to be in gray scale then it will simply delete the whole damn thing.  So this is somewhat of a trial and error process.  If none of this makes any sense to you, don't worry about it and just use Manual processing mode.

Image Scaling
The size of the image on screen can be adjusted as desired using the Scale tool.  This is located near the top right of the Digitizer window just below the toolbar.  The approximate current horizontal scale of the image in pixels is indicated by the pointer.  You can click and drag the pointer to increase or decrease scaling.  Once the pointer has stopped moving the image will be redrawn scaled to the new value in both dimensions.  If you want to increase only the horizontal scale then click on the Width Only option box first (not recommended).  Rescaling to a larger size is often useful in providing better mass resolution for processing.

Reset and Clear All
These are two buttons used for repetitive processing or to restart completely.  If you have processed an image using one of the Automated methods and want to try a different one, or if you decide to try only Manual mode, you can click on Reset to clear the Results list and reprocess.  Reset will retain the calibration data and redraw a fresh image of the plot.  Use Clear All to delete all current data and calibrations and also the plot.  This will restore the Digitizer to its default startup condition.