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GuillermoBarrancos

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  1. I already have a list of 3 potential CCD candidates. G2-8300, G2-4000 and 460EX.
  2. Man Man.... what a work! The more I read..... the more I keep saving up for a Nice mono CCD camera instead.
  3. I'm stunned and speechless! What an amazing piece of work! This is pro-level stuff, going beyond amateur level! The dedication you put into this is really inspiring!
  4. But not all photosites will collect for example Ha during a real exposure of a target, or you would get a completely uniform red block as image. No?So I don't think it's that absolute. At least that is how I interpret all this. Otherwise all sensor QE graphs would show a 75% higher QE in red band for Mono compared to OSC. Some sensors QE graphs don't show any difference in the red band at all! Like the KAI 11002. I stand fully corrected if I'm wrong in the end, when real imaging tests of a Ha region gets imaged 4 times as fast with a debayered DSLR than a normal fully astro modified DSLR. Proof will be in the pudding as they say.
  5. For those interested and not read up on it before. This is a nice image showing the effect of the microlens array on a sensor and why it has such an impact on the QE / sensitivity of the sensor: The microlens basically enlarges the light gathering surface for each pixel, increasing the amount of light reaching each photodiode (pixel) significantly and so increasing the QE / Sensitivity of the sensor. Which reflects in the Sensor QE graphs we see. Removing the microlens array during the debayer process decreases the light gathering capacity of each photodiode (pixel) significantly and so decreasing the QE / Sensitivity. So while, after the debayering, you utilize all pixels when for example using a Ha filter, you will get a higher resolution, but due to the decreased QE / sensitivity, your imaging time (total integration time?) will NOT be shorter than before the debayering. It will be the same or even longer.
  6. How can sensitivity in red pixels for Ha increase by removing micro lens and CFA filter, when sensor QE graphs show the complete opposite? I don't follow. Pretty much all sensor QE graphs I have seen show that a Mono sensor without micro lens has the exact same QE in the red band as an OSC sensor with bayer Matrix. Some actually show even lower sensitivity due to absense of micro lensing! Below graph of the KAI 11002 is such an example. This sensor (both OSC and Mono have micro lensing) shows no difference in QE in red band between OSC and Mono Version: As Canon doesn't produce Mono CMOS sensors of the Digic series, we don't know if a Mono will have a higher QE than a OSC at all and that it might have the same graph as above example of the KAI 11002 sensor. Which would mean removing the micro lensing might have an even more profound impact on QE in the red band with debayering. You end up with a much lower sensitivity. The only gain again being an increased resolution with narrowband.
  7. It was what I feared and why I have been skeptical about the whole debayering. I think we all have been ...how to say.... maybe too enthousiastic too quickly perhaps? Jumping on the hype after seeing some pretty mono Pictures from the first debayered cameras. I think the effect of micro lensing has been (most likely accidently) overlooked and impact it has on QE / sensitivity underestimated. Tho I don't think we immediately have to completely dismiss debayering. If you are after serious Narrowband imaging with a DSLR, then debayering might still be worthwhile risk to take, as you will be able to illuminate all pixels during exposures, instead of just 25%. Getting increased resolution with narrowband filters. But I Guess it's pretty safe to say that if you are just after extra QE / sensitivity, then debayering is a Complete waste of time and not worth the risk!
  8. You have to look at the blue line with the crosses. That is the monochrome without micro lensing.Which is more or less equal to the RGB version with micro lensing. An important clue me thinks as to the effect of DeBayering.
  9. That is for this example CCD sensor. In this case the KAF8300. It seems to be impossible tho to find similar graphs for the Canon CMOS sensors. So then it´s all speculation in how much effect the microlensing has across the spektrum. The only graph I could find is this one from the 40D (which peak QE unmodded seems to be similar to 1100D (36%): So following the trend of the average 10% drop by removing lensing at the 650nm, the effective QE would end up at around 20% in Ha. Fascinating stuff! Really brushing up my Google search skills lately with all these interesting discussions.
  10. I think this is a very nice example of just how much impact that extra 40% in sensitivity has : http://stargazerslounge.com/topic/214878-leo-triplet-tidal-tail-in-2-hours/
  11. In response to the lensing discussion. If you look at the QE graphs of Mono CCD´s. Here is an example of the KAF8300, then you will see that the micro lenses can increase QE sensitivity up to over 40% in the visible spektrum. That´s almost double. Tho in the far red, in general the effect is less to about 20-30% or so. Depending the sensor. Drop off is more in one sensor, less in the other. PS. As note. An unmodified Canon 1100D has a peak QE of about 36%.
  12. Original image by james_screech. I had a go at processing it.
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