Sun

I have previously taken partial eclipse pictures with a variable ND filter and the Pentax's kit lens:

But I wanted to use my 100-300mm Pentax lens, so I bought a variable ND filter for the 58mm size of that lens. This was 120mm I think:

 This was 300mm:

Not the detail of a picture I took with the 5" refractor, but sufficient to show the Moon-god eating the Sun-god on eclipse day, then the corona at totality.

Autofocus doesn't seem to do a good job, but I know it is at ∞.

Even with the filter these are 1/750th of a second.