GC Image Users' Guide
New Features and Improvements in Release 2.1
GC Image Release 2.1 (March 2010) has many new features and improvements. See the
GC Image Users' Guide for full documentation.
High-Resolution Mass Spectrometry
GC Image R2.1 introduces a new version for
high-resolution mass spectrometry (HRMS). This version supports:
- Viewing profile spectra in the more powerful MS Viewer.
- A Mass Calibration tool for quickly implementing local mass calibration
based on chromatographic peaks across the chromatogram. The Mass Calibration tool
offers several alternative calibration functions and maintains user-managed archives
of chromatographic peak sets and calibrant ion peaks.
- A Formula Calculator for computing possible elemental compositions
for selected HRMS peaks. The Formula Calculator supports flexible constraints on constituent
elements (including isotopes) and numbers of atoms. Also included is a
Formula-to-Mass Calculator with isotopes and abundances.
- Graphical overlay in the MS Viewer of isotopic patterns generated
by the Formula Calculator.
New and Improved MS Viewing and Operations
GC Image R2.1 has significant improvements for MS data analysis.
The MS Viewer now supports:
- Displaying and comparing multiple spectra in one window with three new layouts:
Overlaid, Head-to-Tail, and Difference.
- Displaying spectra from the hit-list returned by library search and pushing library
search hit-lists to blob metadata.
- Improved scrolling over the spectral range and enhanced zooming control.
- Control of the color and visibility for each spectrum.
- Arithmetic operations to add and subtract spectra.
- Scalar operations on spectra for addition, subtraction, multiplication, and division.
- Copying a spectrum to the clipboard as a table or string (full range or selected
range) and copying the MS graph as an image.
GC Image R2.1 introduces a Batch Mode for library search with search performance
up to ten times faster than Interactive Mode.
New Tools for Graphics and Meshes
GC Image R2.1 introduces several new and improved features for editing
graphics and meshes.
- Multiple vertices of a graphic object can be dragged in unison in the
Edit Vertices mode.
- Vertices of a graphic object can be dragged in strictly vertical or horizontal directions
with the shift key.
- The new Auto Mesh tool allows automation of vertical
or horizontal mesh divisions (a) uniformly, (b) based on linear retention-time indices,
or (c) based on selected blobs or blob sets.
- The new Polyline Auto Split tool can automatically
find gaps (paths of smaller intensity values) to split a graphic object.
New and Improved Reporting
GC Image R2.1 introduces new user controls for customizing summary reports and other
The Blob Set Table allows user control of
which columns are included and the order in which the included columns are listed.
The Summary Report now supports:
- Saving and reusing multiple Summary Report configurations.
- Reporting in Microsoft Excel file format (.xls).
- User control over the region, size, and orientation of the Image Viewer subreport.
- A simpler mechanism for including a user-selected logo.
- User-supplied comments.
- User control over the inclusion and order of metadata in the Image Attributes subreport.
- Inclusion of an external, user-generated CSV file as a table.
GC Image R2.1 introduces a new interface,
Image Investigator™, which
allows users to analyze multiple chromatograms interactively. Image Investigator
allows users to compare chromatograms, blobs, areas, and blob sets from a set of
chromatograms, and examine the statistical characteristics and trends. In later
releases, Image Investigator will be enhanced with capabilities for clustering,
classification, and fingerprinting. The existing Image Comparison tool, which supports
pairwise chromatographic comparisons, also is included in GC Image R2.1.
Qualitative and Quantitative Analysis
GC Image R2.1 has several improvements for qualitative and quantitative analysis.
- A Reference Peak can be assigned to a
blob to provide additional statistics for quality control, including retention-time
differences, resolutions, and volume ratio.
- The Blob Set Table reports on the residual
set that consists of all blobs not included in any blob set.
- The Area Table reports on the residual area
that consists of all regions not inside any area.
- Linear retention index (LRI) calibration allows users
to set LRI values at the limits of the chromatogram and supports extrapolation.
- The Slice Report now supports multiple calibration functions defined for different
regions in a single chromatogram.
- Users can choose among the total blob volume, area volume, and image volume as the
total response for calculating the percent response for blobs and areas.
- Users can specify the unit of measurement
for calibrated amounts included in reports.
New and Improved Visualization
In GC Image R2.1, the Image Viewer provides several new visualization features.
- Auto Text allows users to select image attributes
(such as source file, sampling rate, modulation period, or user-defined fields)
to be displayed as a text object on the image.
- Users can add a legend with user-defined metadata.
- Users can display an optional colorization legend.
- Users can specify labels for the Column and Column II axes, as well as for the intensity
axis shown in the 3D Viewer.
New and Improved I/O Support
GC Image R2.1 has new and improved I/O facilities.
- Export Image has user controls for the region,
size, and orientation of exported pictures.
- Export Image allows users to export an image
into a one dimensional or two dimensional CSV file.
- Export Image allows users to export the spectra
of selected blobs into a text MS file.
- Additional metadata fields are imported from Agilent Chemstation data files, including
instrument model and sample name.
- Users can add custom metadata fields to the
Other New and Improved Operations
GC Image R2.1 has many other improvements, including:
- Included Graphics and Areas have a new Close
flag that can be used to prevent double counting for polygons inside other polygons.
- The Compound Library now supports chemical name and formula searches.
- The Compound Library allows users to export all or selected compounds to and import
compounds from CSV files.
- The Compound Library has a Description field.
- Blob, Area, Graphic objects and Blob Sets have a new Description field that can
be loaded automatically from the Compound Library (if available) with Auto Fill.
- The software is enhanced to support
importation of Sequence Tables with a flexible CSV Importer.
- The software allows Auto Process of linked
runs from a data path specified in Sequence Table.
- The software allows users to create and manage
additional folders in a project.
- The software provides an option to automatically set the color maps of imported
images to use Default, Automatic, Linear, Logarithmic or Exponential value mapping.
The people of GC Image welcome your suggestions
of new features, your comments about existing features and documentation, and reports
of any problems. We strive to make GC Image meet the needs of our users in
their many varied applications.
GC Image Users' Guide © 2001–2010
by GC Image, LLC, and the University of Nebraska.