6 MP cooled CCD colour camera!!
ISO in the DSLR , I think corresponds to setting the white point. (Because ISO restricts the dynamic range) Thats why astronomical CCD cameras never have or need gain settings because you can do the stretching in the software.
Photo Album:
http://www.flickr.com/photos/14113965@N03/
http://www.flickr.com/photos/14113965@N03/
Anyone knows who designed this camera?
The specs may look great but I have my doubts about their expertise... I think it is not easy to just build a camera... I'd rather go for more established names (but lower specs) at that price.
The specs may look great but I have my doubts about their expertise... I think it is not easy to just build a camera... I'd rather go for more established names (but lower specs) at that price.
[80% Steve, 20% Alfred] ------- Probability of Clear Skies = (Age of newest equipment in days) / [(Number of observers) * (Total Aperture of all telescopes present in mm)]
some thoughts...especially in comparison with the QHY8 which is getting quite popular nowadays...
firstly before everyone goes on cloud nine, the published spec of 1.8" for the chip DOES NOT refer to the diagonal size of the chip. It refers to the lens image circle coverage. The actual diagonal size is smaller. Someone else has also noted that this is a "single-shot" colour chip. It has a RGB Bayer matrix that has twice the sensitivity to sodium light pollution, than it does at "precious" hydrogen alpha where the emissitivity of emissive nebulae lies. On the contrary the Kodak colour chips used by popular established astronomical CCD manufacturers set the minimum gap in the sodium at the hydrogen alpha is closer to the peak of the red pixels, which is similar (matched) to the RGB filters used in monochrome imagers. As for the differences between the SS Pro and the QHY8, the former uses the Sony 413 chip while the latter uses the 435. Note that unlike the Kodak chips, the Sony chips are generally optimized for consumer use, and is more sensitive to daylight subject characters (even though you will start barking at why it is then used in the SS Pro), city lights in the night, while the Kodak one-shot ones happens to be similar in filtration spectrum to an off-the-shelf good set of LRGB filters, with the corresponding peaks closer to astronomical object entities. Note also that Kodak chips has excellent sensitivity to the blue in galaxies, clusters and reflective nebulae.
A little more about the Orion camera, it is manufactured in Canada, and certainly not the same design as the QHY8, although impending rumours seem to indicate this trend. The electonics, drivers, firmware and outer case design are original. However, one good thing is that the cooling performance is 30 degrees below ambient temperature. Note that having a cooled camera is good, but it is no point having a cooled camera without it being able to stay cooled stably at a given specified temperature. You need to take darks in consistent with the light frames at the same temperature for effective noise removal. So how stable is the cooling? I guess it is still early to say. The price you pay is what you get. I have learnt it the hard way in the past. If it is too good to be true, it probably is, otherwise the big brothers of astronomical CCDs will wake up and lower their prices or find lower costs of production. Nevertheless, it is still a fascinating option to consider if one has the dough to experiment and let us all know in this forum!
two cents!
firstly before everyone goes on cloud nine, the published spec of 1.8" for the chip DOES NOT refer to the diagonal size of the chip. It refers to the lens image circle coverage. The actual diagonal size is smaller. Someone else has also noted that this is a "single-shot" colour chip. It has a RGB Bayer matrix that has twice the sensitivity to sodium light pollution, than it does at "precious" hydrogen alpha where the emissitivity of emissive nebulae lies. On the contrary the Kodak colour chips used by popular established astronomical CCD manufacturers set the minimum gap in the sodium at the hydrogen alpha is closer to the peak of the red pixels, which is similar (matched) to the RGB filters used in monochrome imagers. As for the differences between the SS Pro and the QHY8, the former uses the Sony 413 chip while the latter uses the 435. Note that unlike the Kodak chips, the Sony chips are generally optimized for consumer use, and is more sensitive to daylight subject characters (even though you will start barking at why it is then used in the SS Pro), city lights in the night, while the Kodak one-shot ones happens to be similar in filtration spectrum to an off-the-shelf good set of LRGB filters, with the corresponding peaks closer to astronomical object entities. Note also that Kodak chips has excellent sensitivity to the blue in galaxies, clusters and reflective nebulae.
A little more about the Orion camera, it is manufactured in Canada, and certainly not the same design as the QHY8, although impending rumours seem to indicate this trend. The electonics, drivers, firmware and outer case design are original. However, one good thing is that the cooling performance is 30 degrees below ambient temperature. Note that having a cooled camera is good, but it is no point having a cooled camera without it being able to stay cooled stably at a given specified temperature. You need to take darks in consistent with the light frames at the same temperature for effective noise removal. So how stable is the cooling? I guess it is still early to say. The price you pay is what you get. I have learnt it the hard way in the past. If it is too good to be true, it probably is, otherwise the big brothers of astronomical CCDs will wake up and lower their prices or find lower costs of production. Nevertheless, it is still a fascinating option to consider if one has the dough to experiment and let us all know in this forum!
two cents!
the thing about the limitation of the modified DSLRs are the rather short sub-exposure times that one can get when TAKEN IN SINGAPORE before sky fog limit sets in. But this is not to say that they are not good, you still need respectably good dark skies to go long exposures. Faint details will never surface unless you go long exposures, no matter how much one stacks the image. What's not there, will never appear. One can still be happy using a modified DSLR to take DSOs in light polluted environment, colours would be a little skewed, but this is the way it is. Additionally, using a monocrhome camera opens a plethora of choices in colour channel combinations. You are not restricted to the bayer matrix. You can take narrow band filtered images, and it does that pretty well as long as the right choice of chip is chosen.