Nothing very special about this image, taken under a nearly full moon, apart from the beauty of this celestial duo. I am trying to optimise the backspace and tilt in my Samyang 135mm f2 lens and Altair 183C Hypercam. Using a T2 backplate, 15mm adaptor and Altair filter draw, gives a backspace of 44.5mm. I also added 2 x 0.1mm M42 washers total = 44.7mm. This places the focus point bang in the middle of the 'L' near infinity for this lens, which I am led to believe is optimal.
Tilt (rev B) is much better at 12% on a single image, but it looks as if backspace is still a bit off from the aberration inspector (rev C). Interestingly Rev D (mouseover) is the 8 point tilt and HFD value diagram of the final tif image, which looks pretty good at only 6%. The curvature may just be a feature of the lens and/or sub-optimal backspace. What do you think? Any tips/ideas welcome. I can live with this at f2, and use deconvolution and/or astrosharp to improve the stars, or keep fiddling... is it becoming an obsession!
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