Using 3x TV Barlow converted to a 2x by unscrewing the lens and inserting it into an empty barlow tube, with the DMK holding it in place... works a treat :-)
Ah ha! I just noticed that the entry below was dated 3rd June... more sleeeep.
Below is an image taken with my 2.5x TV barlow, I don't think the seeing was quite up to it. Remembering that in the UK Jupiter is very low to the horizon.