Although this my best image of the moon ever, it was a big struggle involving many shots.
Main problems were:
Sigma 70-300mm lens with quite a loose barrel, no extension rings.
Sigma SD1 AF was not at it's finest so I used manual focus bracketing.
No extension rings or converter, so final crop was less than 700px square.
The Giottos 'Silk Road' tripod had the column extended all the way up (duh, I should have sat down).
At 300mm, the lens seems a bit soft.
Workflow.
The SD1 was set up for IR shooting, so I used the Foveon "blue" top layer.
I used the 'mirror-up' function which, on the Merrill has a timer option.
Exported from Sigma Photo Pro as a monochrome 16-bit TIFF.
Labored in RawTherapee to get a decent contrast and sharpness.
Ran it through Piccure+ for even more acutance.
Here we are, for what it's worth, C&C welcome: