| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| stoft | "Hmmm.... The noise appears significant enough that to do amplitude comparisons between filter settings I'd suggest taking at least 3 separate sets ..." | Read more » | over 8 years ago | |||
| stoft | "My guess is that the wavelength transmission curve of the glass (depending on type) softly "rolls off" for shorter wavelengths -- i.e. the glass is..." | Read more » | over 8 years ago | |||
| stoft | "I believe both Excel and Quattro Pro provide for multiple plots. I suspect your's may as well -- in Quattro it's under the specialty xy plotting. I..." | Read more » | over 8 years ago | |||
| stoft | "Not to worry, I too find bits to revise after I publish; what counts is fixing the details as they appear. One thought on visualization. When I do ..." | Read more » | over 8 years ago | |||
| stoft | "Right. That's the Bayer filter pattern which sits in front of the imager chip and gives double the signal sensitivity for Green -- a simulation of ..." | Read more » | over 8 years ago | |||
| stoft | "Good observations! Remember that the AGC is likley based on the sum total over the entire image; not per pixel. If there were independent AGC per c..." | Read more » | over 8 years ago | |||
| stoft | "Jeff, I have a local supplier call Tap Plastics but I assume laser-cut plastics are now available in most metropolitan areas. Ok, that's fine to k..." | Read more » | over 8 years ago | |||
| stoft | "@viechdokter, yes, it was just an experimental baffle for stray light. Keeping reflections low inside the space between slit and grating is necessa..." | Read more » | over 8 years ago | |||
| stoft | "Actually, you need several additional pieces for SWB: 1) average 3-5 parallel lines, 2) monitor stability and take data until it IS stable or times..." | Read more » | over 8 years ago | |||
| stoft | "Ideally, the user would select a "stable" ('smooth' or 'broad peak') region to monitor and then the software would take samples (and average) while..." | Read more » | over 8 years ago | |||
| stoft | "You mean something like this? (from https://publiclab.org/notes/stoft/03-02-2015/plab-3-spectrometer-upgrade-prototype): Yes, mine could be simp..." | Read more » | over 8 years ago | |||
| stoft | "This is and interesting observation and thought experiment. And I'd agree that controlling a light source's intensity while monitoring the camera's..." | Read more » | over 8 years ago | |||
| stoft | "@viechdokter yes, having a stable source helps isolate the noise source. I chose the Solux as I could measure the current as an independent check o..." | Read more » | over 8 years ago | |||
| stoft | "I believe the configuration with 45 and 20 deg was extracted from physically experimenting on the first PLab design. ( I think they were having dif..." | Read more » | over 8 years ago | |||
| stoft | "Yes, I'd agree that time averaging would help and, if possible, it sould be the default to reduce this noise component. I do not have 30 fps data, ..." | Read more » | over 8 years ago | |||
| stoft | "Hmmm... a few counter thoughts. 1) To match the camera optics with the grating to keep the spectral band spread across the pixels seems to require..." | Read more » | over 8 years ago | |||
| stoft | "Jeff; I'm glad I was clear. The mechanics is like the rest; it starts with the objective / spec that it is an optical device. That immediately rule..." | Read more » | over 8 years ago | |||
| stoft | "@viechdokter:, thanks; just a lot of years of practice. Not to worry, your's are logical and thoughtfully organized. Jeff, thanks. Yes, new observ..." | Read more » | over 8 years ago | |||
| stoft | "Jeff, I have doubts about "current bleeding" between the quantum wells as they are isolated from each other with silicon and the conversion to data..." | Read more » | over 8 years ago | |||
| stoft | "Interesting observations. My guess is that IF the camera's sensor responded in a purely linear fashion, the over exposure would be white as you'd e..." | Read more » | over 8 years ago | |||
| stoft | "Unfortunately, LED wavelength does not change with applied voltage or current -- their center peak wavelength is not variable or controllable and P..." | Read more » | almost 9 years ago | |||
| stoft | "Sure ... what's the LED's packaging style/type? SMD, leaded, ...? " | Read more » | almost 9 years ago | |||
| stoft | "BTW .... the comments about LED 'voltage' perspective do not seem inline with LED parameters. With LEDs, it's not the voltage, it's the current you..." | Read more » | almost 9 years ago | |||
| stoft | "Note: Their UV source was a PTI LS-100 fluorescence spectrophotometer -- no longer sold. From a google books print, it sounds like a variable-wavel..." | Read more » | almost 9 years ago |