Comments on: The Camera Obscura and a neat optical illusion

By: anamorphic images! « Dance4

anamorphic images! « Dance4 — Fri, 13 Nov 2009 09:22:25 +0000

[...] just the right angle, snap into an illusion of geometric shapes floating in the air. Care for an explanation of the effect? If photo-realism is more your thing, then you should check out Gillian Brown’s [...]

By: skullsinthestars

skullsinthestars — Tue, 17 Mar 2009 02:56:24 +0000

Shawn: I've been a little hesitant to try and describe the technique in detail, because I'm not completely sure how it was done! It seems that one could use a projector to project an image onto a curved surface, paint it, and then place the pinhole in the position where the projector was. It may be a little more subtle than this, though, because of the optics of the projector, but I'm guessing that this is the basic idea. I made my own crude 'piecewise' anamorph some time ago, to make sure I understood the ideas; you can see the results here.

By: Shawn

Shawn — Mon, 16 Mar 2009 16:38:15 +0000

Very fascinating! Could you explain a little more how the camera obscura can be used to project onto a more complex geometry (ie, not just a flat surface)? I keep staring at the Gillian Brown picture and I can’t seem to figure out how she accomplishes this! It’s truly wonderful!
Any additional insight would be very much appreciated.

Cheers, Shawn

By: Skulls in the Stars

Skulls in the Stars — Thu, 10 Apr 2008 01:45:47 +0000

Making anamorphic images, part 1: Piecewise images…

In my recent post on the camera obscura, I discussed the optical illusion produced by so-called anamorphic images, i.e. images which only appear normal from a particular point of view. One can readily understand such images from the point of view of g…

By: Personal Demon

Personal Demon — Fri, 07 Mar 2008 23:06:19 +0000

And there I go, screwing up my HTML so that I have multiple links to the same page…

Cruel, cruel, irony.

By: Personal Demon

Personal Demon — Fri, 07 Mar 2008 23:05:07 +0000

Egad, Bradley! Your comment is excellent, and the book sounds great, but why all the hyperlinks pointing to the same page? You don’t want to be mistaken for a crackpot , do you?

Seriously, though, thanks for the extra info on Ibn al-Haytham. I look forward to reading your book.

By: skullsinthestars

skullsinthestars — Fri, 07 Mar 2008 20:22:42 +0000

Bradley: Thanks for the comment! You’re certainly right about al-Haytham’s origins; I glossed over it for brevity and just gave a ’summary of a summary’. I am definitely interested in learning more about the man, so I may have to pick up a copy of your book myself!

By: Bradley Steffens

Bradley Steffens — Fri, 07 Mar 2008 16:56:49 +0000

I enjoyed your essay on the camera obscura. I am happy that you mentioned Ibn al-Haitham’s contributions to the field of optics, but I would like to add a couple of points. You describe him as "of Egypt," and it is true that he did some of his most important work there. However, he was born in Basra, a city located in what is now Iraq. As you point out, he was the first person to devise and explain the principles of the camera obscura. What is interesting is that he created the device to test his hypothesis that "lights and colors do not blend in the air." Using pinhole technology, he "forced" light rays to intersect at an aperture and recorded the results in his massive study of light and vision, Kitāb al-Manāzir (Book of Optics). As the first person to systematically test hypotheses with experiments, Ibn al-Haytham deserves recognition not only as the “father of optics” but also as the first scientist. If your readers would like to know more about him, I would like to recommend my new book, Ibn al-Haytham: First Scientist. Written for young adults, it is the world's first full biography of the eleventh-century Muslim scholar known in the West as Alhazen or Alhacen.