Question: Only seeing part of color spectrum

msolomon is asking a question about spectral-workbench: Subscribe to answer questions on this topic

msolomon asked on November 08, 2018 19:39
69 | 2 answers | #17493

The camera I received in my kit is different than the one shown in the assembly. It appears to be working when I plug it into my laptop, and the scale is normal, but when I try to calibrate with the fluorescent bulb, I can only get one half of the spectrum to show up. From one direction, the red, green, and yellow beams appear, and if I flip the camera 180, I see the blue side, but I can't make them appear at the same time. Suggestions?


Thank you both for your suggestions! I have it working now.



Post to this group at


Public Lab mailing lists ( are great for discussion, but to get attribution, open source your work, and make it easy for others to find and cite your contributions, please publish your work at

Log in to comment

2 Answers

I suspect you have a problem with the vertical alignment of your camera. With the camera that originally shipped with the kit there wasn't room to get this wrong. The camera would really only fit one way. I think you need to move the camera up or down - in the direction of the missing part of your spectrum. Its either that or you have your diffraction grating at a funny angle. You don't have the grating in backwards do you? A picture of the insides of your spectrometer might be helpful for diagnosis, showing the position of the gating and camera.

Log in to comment

Hi, I believe this relates to the angle of your camera in the box. If you try to point it further up or down, you should be able to center the spectrum in the image. I hope this helps!

Log in to comment

Sign up or Login to post an answer to this question.