thanks Bruce...

Matt and others,
I am a little lost fellows - see if I'm following this all... You are adjusting BF within each camera setup, and within each camera setup - each possible ND setting.

Yes. I've done that, but it may have been unnecessary work over Gerald's advice. I neglected to take before and after shots from the other modes before opening a rather nice Shiraz and going through all permutations. Sorry.

Now after setting new BF adjustments - is the camera electronics automatically adjusting the BackFocus according to which ND setting and which camera mode you are in...

From talk elsewhere, we're under the impression that the Back Focus adjustment is digital and uses a look-up table which may not have been calibrated to the lens or may not contain all permutations. It's all conjecture, so my initial FB cycle at all three ND settings appears to be a 'good thing'. The rest of my activity may only be the equivalent of waving a rubber chicken over the camera, but it passed a beautiful evening.

Or will you need to physically adjust backfocus everytime you make an adjustment to ND or camera mode or change the battery?

No - I am working under the assumption that you'd have to do a full hard reset to lose this information, certainly not a power cycle. I might re-check if I did a soft reset.

Another thought that passed my mind this evening is that Patio Doors may be the perfect answer, and the 9-12 star charts weren't strictly necessary. Just something with some contrasty lines both in close up (door handle) and wide (patio door). Just pontificating.

Thanks Matt - and long live a fine drink, lovely evenings, and British Humor...

The patio doors are essential. Its the ratio of backfocus charts to glass area that is the key.

Seriously though I suppose the auto back focus needs something bigger to work with. Whether the different settings are really needed is something that perhaps Sony could tell us. Having back focused Fujinon 2/3" lenses for years with just one chart the procedure now developed is intriguing.

Seriously though I suppose the auto back focus needs something bigger to work with. Whether the different settings are really needed is something that perhaps Sony could tell us. Having back focused Fujinon 2/3" lenses for years with just one chart the procedure now developed is intriguing.

Bruce

The key is 'auto' back focus. When you do your manual back focus, you know you want to focus on the chart. The camera's auto FB routine sets the zoom to wide and then focuses on the most contrasty thing in frame. If this happens to be a few feet further away than the now tiny backfocus chart, it is not surprising that the camera gets confused :-)

Nick