Yesterday, the new Spectragryph version v1.2.8 was release. There have been a couple of improvements around the webcam-based spectra acquisition:

• changed "USB webcam" control to DirectShow => wider range of cameras accessible, direct control of more settings ¶meters.
• direct access of exposure time for those USB webcams that allow it via DirectShow. Turning off AutoExposure, AutoWhiteBalance, AutoBrightness, AutoSaturationControl.
• framegrabbing window for USB webcams now has "full pic." button to fully show large images
• define USB webcam settings in Settings window, save & load as device settings file.
• automated loading of device-specific settings file on connect. Permanently assign a settings file in Options window.

What does that mean?   >>> reproducible spectral data acquisition <<<  !!

By turning all the autosettings off and making exposure time accessible, you can now define appropriate exposure times yourself (to avoid clipping!) and keep them stable. When measuring absorbance, no AutoExposure function will any more destroy the relationship between measured reference intensity and sample intensity.

This is like BAAAMM, when compared to the previous situation. I hope you like it. There will still be some really cheap webcams that won't let their exposure time settings be changed, sorry for these.