Autofocus for Large Format

[John Jarosz]

But it's after the fact

http://tinyurl.com/232okya

[Nathan Potter]

Also known as a fly eye lens - an array of tiny, usually simple lenses where each microlens sees the same scene but from a slightly different angle. Neat idea to use the array to reconstruct an in focus image from out of focus COC. Huge software problem though, so a lot of signal processing required, not to mention other limitations such as poor image quality from the presumably simple microlens. Can't quite figure out how to extract a sharper image from overlapping Circles Of Confusion though, then return a sharp image that approaches the original scene reality.

Nate Potter, Austin TX.

[feppe]

Not sure if this is related.

[BetterSense]

I designed an autofocus system for my Speed Graphic that used an ultrasonic distance transducer thing that could work out to 25 feet. I never implemented it though because it would be pretty pointless.

[Struan Gray]

http://graphics.stanford.edu/papers/...era-150dpi.pdf

This is another take on Lippman's 1908 direct imaging camera, and is related to screen-based and lenticular autostereograms and colour processes like the early Kodacolor movie film. In all cases you give up spatial resolution at the focal plane to record spectral or angular data.

This page has a useful set of historical documents for download:

http://www.umiacs.umd.edu/~aagrawal/...eldCamera.html

[feppe]

Oh, and also plenoptic cameras.

[ignatiusjk]

NEVER !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! That's the choices you make when you go LF. Using a loupe,manual f stops,etc that's all of the fun of LF.