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Author Comment Last activity Moderation
Rural "Magic Lantern seems to run on the EOS M and has an intervalometer. I can't recommend Magic Lantern enough. I've got an EOS 600D/T3i that I much pre..." | Read more » over 6 years ago
stoft "Since you appear to have verified all the individual elements, the solution must be that your overhead "fluorescent" ceiling lights are not the typ..." | Read more » over 6 years ago
smurpau "Yeah, the webcam itself gives a good image and is focused. Moving the diffraction grating from 60 degrees to 45 degrees on top of the webcam gave t..." | Read more » over 6 years ago
stoft "Ok, still a mystery; but I'll bet it's something simple that's overlooked. Let's double-check the obvious. In room light, the webcam by itself shou..." | Read more » over 6 years ago
smurpau "Welp, still no luck, although the purple tint does appear to reduce the clipping (presumably just by absorbing some of the incident light) " | Read more » over 6 years ago
smurpau "You know what, you're right. I don't see anything reflected from either side through the ethanol-washed piece, but I do through the original purple..." | Read more » over 6 years ago
stoft "Ok, it was just a reflection in the earlier photo. Just good to check. Could there be any issue with the DVD as a diffraction grating having been a..." | Read more » over 6 years ago
smurpau "Is this the paper holder you mean? I can't see any real gap from the front or back. I tried the spectrometer with the slit reversed as well (I'll t..." | Read more » over 6 years ago
stoft "Quick question .... in your photo above (of the 0.4mm slit) it looks like there is a gap between the slit film and the paper holder for that film. ..." | Read more » over 6 years ago
smurpau "Yes, this is the fluorescent tube 0.4mm slit diffraction grating and webcam As I said I've focused the webcam without the diffraction grating..." | Read more » over 6 years ago
warren "I think the best plan may be to try focusing the webcam with the spec open and using a webcam program. It should be focused as it ships, actually. " | Read more » over 6 years ago
warren "Hmm, I can't see any spectra on your profile at https://spectralworkbench.org/profile/smurpau Are you sure the earlier spectrum you posted was a f..." | Read more » over 6 years ago
smurpau "Thanks for your reply @stoft. The light source is a fluorescent tube (there aren't any CFLs available here). I also have a green flashlight and my ..." | Read more » over 6 years ago
stoft "Hmmm. Well, I'd agree the above image seems "fuzzy" but I'm also not clear as to what light the spectrum is representing. It also looks very over-e..." | Read more » over 6 years ago
smurpau "I have the v3.0 kit but can't get a focused spectrum no matter how far I turn the focus ring clockwise or counter clockwise. The diffraction gratin..." | Read more » over 6 years ago
cfastie "Hi CHUMBA, I have never seen the inside of a Samsung camera, so I can't be of any help. There is probably a filter somewhere. Maybe it is glued to..." | Read more » almost 7 years ago
CHUMBA "Hi @cfastie, I wonder if you know How take out the IR filter from a Samsung DV150-f, I have one, I broke it, and I did not find the IR filter anywa..." | Read more » almost 7 years ago
HalLasell "This is an old thread, and this has probably been resolved. However, Matlab has tools which enable which support conversion of Matlab code to C co..." | Read more » almost 7 years ago
khufkens "@warren, not sure it justifies a separate page yet, my comment is rather low on details / text. I would need to put some context to it all if this ..." | Read more » about 7 years ago
warren "Wow @khufkens, I think your graphs and notes merit a new research note... We could link it to this note as a followup? " | Read more » about 7 years ago
khufkens "Related, I found this post, discussing in part the asymmetry in the current desktop spectrometer design. I'm designing a symmetrical layout similar..." | Read more » about 7 years ago
straylight "thanks khufkens, interesting graph and really well presented. On a qualitative level, you can see this by shining the red laser through a DVD grat..." | Read more » about 7 years ago
khufkens "I'm making a simple spectrometer to extract the spectral response curves of an imaging sensor. To this end I made some calculations to help me desi..." | Read more » about 7 years ago
mathew "thank you for these conversion details and trying to get to the bottom of this problem. " | Read more » over 7 years ago