Introduction
Many spectral line profiles reported elsewhere on this blog frequently take advantage of a very versatile software package called Spectragryph. The software was developed as a successor to an earlier version for managing and processing spectral data called Spekwin32. Both apps were the creation of Dr. Friedrich Menges who, since 2016, works full time on maintaining continued support.
Most important of all, Spectrogryph is entirely free! It is highly recommended for any home experimenter and amateur scientist who has an interest in optical spectroscopy.
At the moment, Spectragryph is only available for Windows, but works fine with all OS’s from Windows 7 through to Windows 11. The full package can be downloaded for a trial period, and when that expires you can simply email Dr. Menges and request a lifetime license for non-commercial users.
Main Features
Spectragryph is a general purpose optical spectroscopy package for the acquisition, plotting, processing and analysis of data from spectrometers. It is extremely flexible and employs a Windows “ribbon” type menu hierarchy quite similar to the standard Microsoft Office apps.
Here is the main display with explanations of some of the main features:
Most CCD and CMOS spectrometers from device manufacturers come with their own data acquisition and presentation software routines. But in many cases these features are limited and they are “tied” to the spectrometer hardware from the manufacturer.
Spectragryph has built-in data import possibilities from an impressive number of manufacturers. Below are brief mentions of the various menu choices available for manipulating spectrometer data…
Acquisition Menu
Spectragryph is able to acquire data directly from a good range of spectrometers and change the control parameters such as CCD temperature, Raman shift parameters and other instrument variables. And the list is always increasing. It can handle spectral data files in its own native binary format, and save them as a JCAMP file, GRAMS SPC format or Excel compatible ASCII.
Once the spectral data have been acquired (and saved), this opens the many other features of Spectragryph to plot, process and analyse spectra…
Plot/View Menu
This menu has the usual features for changing the colour, thickness and appearance of line traces. Multiple spectral curves can be stacked or overlaid, the wavelength axis reversed, peak wavlength labels applied and other useful changes made.
There is also a feature called “spectroscope” that adds a continuum spectrum as a rectangular pane to the bottom of the main spectrum window. This can be aligned with the x-axis to provide the correct wavelength vialue and then “activated”. This can be useful for displaying emission line and band spectra, as shown in this example for a Bunsen burner flame spectrum:
Process Menu
One very useful feature of the Process Menu is shown here, with an example of baseline adjustment and correction for the absorption spectrum of iodine. This spectrum was reported in an earlier post, which exhibited a broad background with superimposed vibrational structure:
Analysis Menu
This menu has comprehensive analytical routines for analyte concentration calculations, peak identification and area determinations plus a very useful film thickness routine for reflectance spectroscopy.
Below is an example of a film thickness calculation, determined from an interference pattern obtained by reflectance spectroscopy.
Other features of Spectragryph include analysing fluorescence spectra and displaying an EEM (Excitation Emission Matrix), a section for automating repetitive processes, and a menu devoted to identifying unknown samples using spectral library database searches.
Conclusions
The Spectragryph site has a good number of tutorial videos to assist newcomers together with a large number of screenshots and Help pages.
All in all, the Spectragryph software package for optical spectroscopy is well worth a look. It should prove very useful for the home experimenter in optical spectroscopy.
And before you ask… no, I am not getting any incentives for this short review! 😁
