How much of an ND filter for Venus transit?
I also use the Baader solar film, ordered a sheet and made a holder that slips over the end of my telescope. Good stuff, and you'll get any visible sunspots in your pictures too. I definitely would not trust ND filters for optical viewing. As far as shooting with only the LCD, not sure how well that would work. If you can get the solar film, I think that's the way to go. It's effective and safe. And, when I got a sheet, I had enough to cut out filters for both my telescope and binocular lenses.