Re: Lena's Birthday Question: Neatest Optical Hacks

Dave Schaack wrote:

Yes, folks, that's right! Once again, this Friday (March 31) is the birthday of Lena Sjooblom, the November 1972 Playboy model whose face is so familiar from so many bad image processing papers.


Are you saying that if a paper includes this image, it is bad?

I wish it were that simple. No, I don't mean that--only that image processing is not in general the panacea that it's sometimes cracked up to be--so that a great many image processing papers are in fact bad, whether Lena and her ostrich feather are in there or not. We talked about that on last Lena's Birthday, as you can read in Google Groups. I'm not down on the entire field, but I'm sick of reading about how the Latest And Greatest Technique can make blurred pictures of ugly people into sharp pictures of pretty people, or in general how postprocessing can be used as a substitute for good data. It can't. Like a Crescent wrench, postprocessing has its place in the toolbox, but it isn't for everything.

Since it's now officially Friday, and because I still want to have a conversation about good stuff rather than bad stuff, I'll post a few of my favourites. We're talking *hacks* here, so I'm leaving out Maxwell's equations, the laser, and so forth.

1. The achromatic lens. Optical instruments basically wouldn't exist without it--and it's all done by kluging together the properties of glass made with and without lead oxide. Having three surfaces instead of two then made possible better monochromatic aberration correction, but it's still a hack.

2. Pitch polishing. Who'd have thought that you could sustain nanometre precision over tens of centimetres using a potter's wheel, tree sap and rouge?

3. The ruling engine. Long before laser interferometers, mechanical averaging made possible the construction of grating devices accurate to a small fraction of a wavelength of light, in the Victorian era no less.

What are some of your favourites?

Cheers,

Phil Hobbs
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