For the numismatists among us

[canonian]

Photographer Martin John Callanan is working on a project to photograph the coins of 166 countries titled "The Fundamental Units".
Read more at http://greyisgood.eu/units/

His extremely large prints took three days of processing 4000 stacked and stiched exposures and made with an Alicona infinite focus 3D optical microscope.
http://www.npl.co.uk/news/big-photos-of-little-coins
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Fred
Canonian@Flickr

[Craig Gerard]

Fred,

Excellent!

Thanks for the link.


Craig
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To use a classic quote from 'Antz' - "I almost know exactly what I'm doing!"

[Chris S.]

If it is taking three days of processing to stack and stitch 4,000 frames into a 400 megapixel image, something seems terribly inefficient. That photographer might benefit from joining this forum. . . .

--Chris

[canonian]

[canonian]

[Chris S.]

If that was the entirety of Martin John Callanan's response, it wasn't very informative.

I'd already perused the Alicona Website (though had not viewed this particular video). Alicona's hardware doesn't strike me as being all that innovative--basically a metallurgical microscope with an automated Z-axis, axial lighting, and a motorized x-y stage. Yawn. I did wonder whose objectives they are rebranding. They have a 100x with 3.5mm working distance; wonder what its NA is, and if it is apochromatic?

Their software might be well-executed, if perhaps not as innovative as their marketing suggests. But as a turnkey system, the whole setup seems nicely integrated for certain users--at least in this marketing video, which used a pretty easy example.

I'm curious about what is meant by "modulated" light. I wonder if this is just a branded term for a simple, gated (axial) light source, or something more? If I were doing what they are doing, I'd use continuous light behind a rotating disk with a hole in it. Coordinate the rotation of the disk with x,y,and z movement, and one could nicely gate the exposures on a shutterless sensor, without the delay or heat build up associated with flash fired from capacitors. Seems sort of obvious--is that all there is to it?

On quick glance, their patents look rather weak--but the claims are in German, which I don't read, so I'm getting only the abstracts, and may be missing a lot. If some of our German-speaking forum members get a chance to read the claims, it would be interesting to know if there is more going on here.

--Chris

[canonian]

[ChrisR]

They look like Nikon LU as here;
http://www.nikon.com/products/instruments/lineup/industrial/industrial-microscopes/accessory/objective.

Search found this which may go further...
http://www.alicona.co.uk/home/products/infinitefocus-standard/focus-variation.html

And may be related to this
http://www.microscopy-analysis.com/news/alicona-launches-infinitefocus-sl-3d-microscope-and-profiler-measuring-tool-materials-science

"The illumination is provided by a patent-pending dual ring LED concentrator optics system with segmental control allowing the optimum illumination of the object being scanned. "

I'm sort-of surmising that they're getting depth information as they focus through the surface.
We know that if you move the illumination the Out-Of-Focus blur moves, so perhaps they're moving the light ("Modulating" those leds?), and repeating the measurement, to get better accuracy.

I didn't come across a link to the German patent..?

[Chris S.]

[ChrisR]

I looked through three pages of search results as before, with Patent Applications plus various names, and it doesn't appear. (Time to change my IP address again!)

The (only) unique feature seems to be the "liquid lens" which is electrically controlled to refocus quickly.

[abpho]

Wow. Very cool. Wish I could play with that.
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I'm in Canada! Isn't that weird?