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atik 414EXC vs ASI1600MC

using M82 for comparison, here is the picture from ATIK414 EXC ( CCD) colour and ASI 1600MC(CMOS)

both are cropped and re-sized to make them to same pixel sizes as close as possible

ATIK414EXC:


ASI1600MC:

If at 100 % magnification, ATIK414EXC is definitely better. By getting the statistics using AstroImageJ, histogram on ASI1600MC shows truncation on values, not sure if it is due to stacking.


 ATIK414EXC:

ASI1600MC


If the scale is reduced, then they are closer in image quality

this is histogram of ASI1600MC after reducing the picture size:



Noise level on background: ATIK414EXC is better
Dynamic range: ASI1600MC is better

The galaxy is more prominent on ASI1600MC,and thus higher contrast to the eye. But the stars on ATIK414EXC looks more natural in brightness. Might be ASI1600MC's stacking is bit overdone

So ATIK414EXC, though a CCD at a much lower resolution ( 1384 x 1032) , but based on ExView HAD, is still very competent overall, if you can accept a bit higher level on noise levels, ASI1600MC needs longer integration time to achieve similar levels, taking darks , and bias calibration to remove the artifacts( Amp glow, FPN), but the final result is slightly better.

as CCD is using a single amplifier on chip for pixels, it is free of FPN(Fixed Pattern Noise)
And this version is actively cooled, blooming can be avoided, and bias frames are not necessary

However flats are defiinitely needed for both CCD and CMOS to to correct vignetting, dust, or smudges in your optical train


All the images are from DonBoy's flicker
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