Although the planets were slowly climbing higher again, the maximum altitude for Jupiter was still only 40 degrees above the horizon in the Summer of 2022 (Saturn only got up to 20 degrees!). So when I ordered my ASI462MC color camera, I also added a ZWO Atmospheric Dispersion Corrector. The ADC increased the distance between my barlow and camera sensor, which led to an increased focal ratio of about F/17. This higher sampling should be better for the small 2.9um pixels.
The tests on my first light indicated I had to move the primary mirror forward to reach focus with the ADC in the imaging train. So the next day I unscrewed the primary mirror cell, moved it to the next set of holes in the carbon tube, and re-collimated the mirrors. I think I finally have a good understanding of both Newtonian collimation and how to properly use my high-quality tools to dial in that collimation. That should definitely help with getting the best possible image resolution from that 20 cm primary mirror.
Long image train: ASI462MC – nosepiece – 1.25" filter – ADC – 3x barlow – 1.25″ concentric adapter – 2″ extension tube – focuserTo adjust the ADC levers, I slewed to Jupiter and used the handy 1-click ADC tool in FireCapture. The RGB data was immediately so much sharper than my first light with the ASI462MC!
I also swapped out the luminance filter for an Astronomik 742 nm IR-pass to test the near-IR capabilities of this camera. The raw IR images came out purple with the default WBlue=95 and WRed=52 settings because the IMX462 Bayer filter transmission only equalizes
past ~825nm. Color balance was adjusted in post-processing to achieve a neutral color in IR.
RGB single 60 second capture @ 200 fps. Best 50% stacked.
IR742: 60 second captures per stack @ 50 fps. Best 50% stacked. 3 stacks derotated in WinJUPOS.
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