| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| viechdokter | "I could re-scale but ... when everybody here gets the same minimum 2.55 increments here and you want reproducible spectral data then everyone shoul..." | Read more » | almost 8 years ago | |||
| stoft | "Hmmm, well the RAW data should have the same scale units which would be unsigned 8-bit integer from 000 to 255 -- so the Y axis should show noise h..." | Read more » | almost 8 years ago | |||
| viechdokter | "I took the data from the CSV files that Spectral Workbench provides with my spectra. I had a look at one of dhaffners spectrum CSV files and see th..." | Read more » | almost 8 years ago | |||
| stoft | "Well, except there's still a problem with the plot. The smallest increment looks to be '4 steps' per scale units of '10'. Either there was some mul..." | Read more » | almost 8 years ago | |||
| viechdokter | "Okay, here I combined the 4 channel max/min-difference curves in one diagram so they have the same vertical scale now: And here the combined dat..." | Read more » | almost 8 years ago | |||
| viechdokter | "Talking about bits and quantization: I also noticed that certain values (2.55 and multiples thereof like 5.1, 7.65 ...) appear in every spectrum's ..." | Read more » | almost 8 years ago | |||
| stoft | "Yes, it's called quantization; the camera only has 8-bits and the scale of the two plots is likely about 3-5x different. Take a look at the 'red' p..." | Read more » | almost 8 years ago | |||
| warren | "Hmm, very interesting -- without vertical scale its hard to say though - I believe the "plateaus" on the "average curve" are artifacts of the preci..." | Read more » | almost 8 years ago | |||
| viechdokter | "@warren:They would be low-noise green if you average them. ;-) @stoft: BTW, I noticed that curves that were averaged over two or more channels l..." | Read more » | almost 8 years ago | |||
| warren | "Would he be low-noise green? :-) I'd also love to see them plotted on the same graph, maybe with the graph lines themselves in appropriate colors...." | Read more » | almost 8 years ago | |||
| viechdokter | "Yeah, I think I could do it. Hmh, I must admit that I only pretty recently started to use Excel-like programs at all. To be honest, your research n..." | Read more » | about 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 » | about 8 years ago | |||
| viechdokter | "Yes, you are right. I, too, like comparable curves better. I used LibreOffice, a kind of public domain "Excel". It plots diagrams automatically and..." | Read more » | about 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 » | about 8 years ago | |||
| viechdokter | "@stoft : sorry I had to revise the research note as there was a big mistake in the red curve. I exchanged it with the new revised red curve and now..." | Read more » | about 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 » | about 8 years ago | |||
| viechdokter | "@stoft : RGGB like in this picture? " | Read more » | about 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 » | about 8 years ago | |||
| Joeri2 | "I read that. I tried anyway just to check if there was anything perhaps a small difference. And so far I noticed a completely different problem. I..." | Read more » | over 9 years ago | |||
| MrBumper | "I'm not at all sure you can measure what you seem to be talking about, or at least not in the way you seem to be going about it. As far I know the ..." | Read more » | over 9 years ago | |||
| mathew | "This sounds like a great idea! Getting the lighting conditions and reflections to a minimum will be crucial to making this work. some flat, diffus..." | Read more » | about 10 years ago |