Transmission – SpectraWiz Quick Start
- Turn on the computer. Open the StellarNet software by double clicking on the desktop icon SpectraWiz to open the application.
- When you first open the software, you should see a screen that looks like:
- Turn your light source on and have no sample on the fixture. Set the integration time so that your spectrum, in the SCOPE mode, is not saturated but as close to 65,000 counts as possible. Click on the integration time icon
(and type in a value between 1 and 1000 ms) or use sliding scale 
. In the first picture below, the spectrum is correctly optimized to be right below the saturation limit (65,536 counts). If a portion of the spectrum is off the screen reduce the integration time. The goal is to maximize your signal in SCOPE mode. You want to adjust your integration time until the spectrum fills most of the SCOPE graph (65,000) without saturating. This is also the time at which you should adjust the number of scans to average (more scans averaged will increase accuracy, but will take more time for each reading). You can also add smoothing controls at the time too in the setup tab. A pixel box car set to 3 and averaging set to 5 often gives nice results. 
- After optimizing your conditions, turn off or block the light source from the spectrometer. You should see the baseline is flat, but slightly above the zero value. You may also see some peaks from overhead lighting. First, right click on the dark light bulb to release any previous darks taken. Wait a cycle and left click the dark bulb to take a dark. You should see the baseline drop to zero.
- Turn your light source back on. You should see that the spectrum is now flush against the x-axis. With no sample in place click on the yellow light bulb. This is your reference measurement (100% transmission)
- Now you can navigate to %T:R mode by clicking %T:R or clicking view-> transmission.
- With no sample in place you should see your transmission/reflectance line to be fairly flat at 100%. Note that %Reflectance and %Transmission are mathematically equivalent.
- Place your sample below the probe holder and you should see your reflectance curve. To open the color application, go to Applications -> CIE Color Measurement or click the color icon.
- Save your sample by clicking the floppy disk icon or clicking File -> Save.
Your saved file will be a .TRM. This is a simple text file and can be opened in virtually any program.
Tags: Application, Software
