Monday, November 16, 2015
Replacement camera for my Lu055M
Since the death of my Lu055M, I had been trying my ASI 120mc on H-alpha imaging but the result is acceptable at best. I had an ASI 120mm before, but the newton's ring is too annoying so that I sold it soon. The image taken with a 120mm is great, however. I was impressed from the image on the real time screen, not to say the stacked version! I had been looking at those CMOS camera again, and I had one in mind and it features a CMOS sensor which should have newton's ring problem! The chip size is bigger, big enough to fit in the whole solar disc with my Ranger and it has 5 mega pixels and so I have no more need to make mosaic. With my Ranger which has 480mm focal length, the solar disc image would be smaller than 4.2mm but of course, with the prominences at the edge and it might exceeds the size of the CMOS sensor a bit. To elminate the newton's ring, the simplest way is to let the solar disc to drift round the sensor while capturing. Flat field might not work since the pattern of the newton's ring might change rather rapidly even if the solar disc moves a little bit in the field. Let me see how it works out, and the bottomline is that, it's going to be a fine lunar camera.