Playing with post focus and stacking

[davidedric]

Panasonic has introduced a new mode in it's latest cameras with 4K video and DFD focusing, called "Post Focus". The camera looks at the scene, then produces a two second video in which it progressively focuses from the nearest thing it can find to the furthest. The different frames can then be extracted as 8mp stills using, in my case, Lightroom. (You can do all of it in-camera, too, but I find it easier on a big screen.) The general idea is that you can pick the frame with what you want in focus, but I wondered what would happen if you took a bunch of frames, and then stacked them.

It's going to take a lot of experimentation to see if this is worth doing, but it's darn clever!. The stills don't have any exif, so I'm going to have to menu diving to try and fathom what settings are being used. But any way, here's a play with about a dozen frames loaded into a trial copy of Zerene. Nearest frame, furthest frame, and stacked result.

Dave

[Shadowman]

Nice, did it look like it ever focused on the wall?

[Black Pearl]

Thats a very clever feature and a superb result too.

[John 2]

I guess it had to wait for 4K video to achieve a level of quality Dave but it's a great idea.

[DanK]

A very interesting development. I had read about (but hadn't tried) extracting stills from 4K video, but I hadn't heard of a camera that makes use of this by varying focus automatically. Very handy if it turns out to work well. The stack seems to have worked out well. However, it looks as though you may have too few slices for whatever aperture you used because there are some areas that appear not to be fully in focus. It's hard to tell at this resolution, but looking at it in the lightbox, it looks like some of the petals are soft. Or am I imagining this?

[davidedric]

This was very much a first fumbling. I selected one in three frames, for no very good reason. I was using a m4/3 lens (obviously) with a maximum aperture of 2.8, so I figured the Dof could not be too shallow.

I don't know how the 4K mode sets aperture, need to do some experimenting. I guess it's worth doing some, though.

Dave

[Dave Humphries]

Interesting Dave, thanks for sharing.

[dem]

This is neat. I am surprised that Panasonic have not provided focus stacking option as part of their software.

[DanK]

Dave,

My tiny stick-it-in-the-bag-and carry-it-everywhere camera is a Lumix LX100. It can extract 8 MB photos from 4K video, but it doesn't have post focus capabilities. Sigh.

Dan

[davidedric]

May be interesting, or scary, that Panasonic delivered this capability with a firmware update

[tao2]

Or....

Instead of 8 fames in 2 seconds then choosing one, say another 5 mins. - ye could just focus on what ye want and take ...say..1/250th of a second?

Not wishing tae rain on parades...

[davidedric]

Not raining on anyone's parade!

More an illustration of what possibilities may open with new technology, and how technologies developed for one purpose can be put together and combined for another (and in this case via firmware).

I still sometimes see posts (not here!) saying that mirrorless cameras are slow to focus. Not any more they ain't.

Dave

[IzzieK]

Interesting new concept, Dave...thanks for sharing...