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

[Craig Gerard]

Fred,

Excellent!

Thanks for the link.


Craig

[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]

...That photographer might benefit from joining this forum.

Definately, we could learn him a trick or two, or he could learn us?
Wonder how he did this, I can only imagine he stitched 200 pictures, each of a 200 shot deep stack... or something?
Or maybe rented the microscope 1 hour a day?
Numerous scenarios spring to mind but I'm very curious, I might even ask him.

[canonian]

If it is taking three days of processing to stack and stitch 4,000 frames into a 400 megapixel image, something seems terribly inefficient.

Well, I wrote Martin John Callanan, asking him about the number of shot and the methodes involved, and he was kind enough to answer my questions:

"We were wondering about the technical details of the "Fundamental Units" exhibit and the way --or the workflow-- how these photos are taken, especially the way it took 3 days and 4000 shots interests me."

Mr. Callanan replied:

"The article mis-quotes the time involved. We use a system based on this:"
http://www.youtube.com/watch?feature=player_embedded&v=GXJmixXi6ao

[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]

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

Yes, that was his responce. No more, no less. But I was glad he took the time to answer and gave us a small lead.

Yawn.

I'm a bit of a hardware geek so I'm easily impressed. I had the opportunity to play with the Hirox KH-8700 3D Digital Microscope and the operator showed me the same principle of measuring depth by focal plane and produced the same 3D mesh/wireframe/textured object, resulting in a freely rotatable 3D-object and stored the information for off-line (without the subject present) calculations and measurements. The resolution was somewhere within the microns. In the video it is a bold claim that Alicona could do measurements withing the resolution of 10nm.

Their software might be well-executed, if perhaps not as innovative as their marketing suggests.

'Innovative' is a marketing term that wears of soon. Compared with what I have seen in the video the possibilities I've experienced with the Hirox KH-8700 however were IMO innovative, very versatile, and all with a great ease of use.
We did a couple of surface measurements and were able to distingues the different chemical layers of a 19th century daguerrotype plate. Within a minute. Pretty amazing.

I'm curious about what is meant by "modulated" light.

These flashes could very well explain the claim of 4000 exposurees I guess?

I wonder if this is just a branded term for a simple, gated (axial) light source, or something more?

Whatever it is I'm always interested in unfamiliar lighting techniques and will dig in their site some more.

[ChrisR]

They look like Nikon LU as here;
http://www.nikon.com/products/instrumen ... /objective.

Search found this which may go further...
http://www.alicona.co.uk/home/products/ ... ation.html

And may be related to this
http://www.microscopy-analysis.com/news ... ls-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.]

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

I should have said, "patent applications." And today, Google Patents is translating for me--something it wasn't doing last night.

Here is one European patent application. There are other versions (though with a lot of overlap) available by clicking on the names of the inventors or applicant. There may be more out there--my search was by no means exhaustive:

http://www.google.com/patents/EP2132524 ... CDoQ6AEwAQ

--Chris

[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.