[bojan]

In order to make wavelength calibration easier and more accurate (especially when there are no prominent spectral lines in the spectrum), I put together this gadget.
It is assembled with already made parts from my other projects (like SHG, which is still in pipeline), old 50mm lens (Domiplan 2.8). So instead of slit, I used aluminized optical fiber, illuminated with neon lamp (mains indicator), but of course other light sources can be used.
The results look promising, but something seem to be wrong with my polynomial interpolation of wavelength points (BASS app).. I am not sure why the calibration is shifted in the middle, while entering wavelengths, all looked OK (I used 4-polymomial interpolation).. I asked for help in GroupsIO, maybe someone will know what I am doing wrong.
This experiment was done with Tair-11A+Canon 450D (modded), now I have to try it on C11....