On an evening of superb seeing, I had a short session on Mercury before it got too low, after which I went across to Venus:
https://www.astrobin.com/i3t186/ I decided to use the Chroma Methane Band filter, mainly because, even with the narrowband (20nm), Mercury is so bright that there was no problem achieving the histogram and frame rate. As I see it, the advantage of the CH4 filter over an IR Band Pass filter, is that it obviates any atmospheric dispersion that will be occurring across the Band Pass wavelengths. Clearly with Mercury being low to the horizon, atmospheric dispersion is at its worst. I have generally found the Methane Band filter gives better clarity than say my 850nm or 642nm BP filters.
Clearly seen, is the prominent Kuiper crater, south of the Equator towards the Terminator.
Again the edge diffraction effect limits resolution near the limb, but the correlation with the WinJUPOS graphic and the Melown Technologies map (Version C) is quite good. It is pretty clear to me that the bright ray from crater Hokusai, which lies beyond the upper right limb, and transects Crater Kuiper can be seen in my image.
I also made a GIF animation of my image and the WinJUPOS graphic to make it easier to identify the features. Version B which can be accessed via the mouse over.
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