New Pepper's Ghost art toy

[P.T.Widdle]

http://shop.crayola.com/toys/creative-a ... 00000.html

[Richard Kaufman]

I don't believe this qualifies as a Pepper's Ghost: no glass or mirror.

It seems more like a "Lucy" to me.

But it's very cool!

[Travis]

I see a piece of glass, or plastic, of some sort positioned at an angle in front of the viewing instrument.

[Dustin Stinett]

It's not The Ghost. This "projects" a two dimensional image onto a flat surface (in this case a piece of paper). That is not at all the kind of thing created by the optics of Pepper's Ghost.

[Brandon Hall]

I thought this was more closely related to the camera obscura allegedly used by Vermeer, but I could be wrong...

[Dustin Stinett]

Good call Brandon; that's exactly what it is (without the pesky box).

[John Signa]

This looks very similar to an art toy that I had as a kid.

No projection is involved. You're looking at the object to be drawn through a darkened piece of plastic at an angle that reflects your drawing.

[Bill Mullins]

Not to get all physics/optics on you, but . . .

This is much closer to Pepper's ghost than a camera obscura. Pepper's ghost uses a partially reflective surface so that when you look in a particular direction, you see the object behind the surface, and another object reflected in the surface, and both appear to be in the same direction from you. This toy does the same thing -- the green frame has a hole to constrain your eye to be in a specific place, and behind it is a small partially reflective surface. When you look through the hole, you see (through the surface) the object you want to draw, and you also see (on the surface) a reflection of your hands and the drawing. Since the reflective glass is so much smaller than one that would be used in a theatrical PG, it has to be much closer to your eye so that it covers your entire field of view, and your eye has to be in the exact spot behind the hole for it to work.

Richard said it has no glass or mirror, but you can see that it does on the illustration on the front of the box.

A camera obscura is a lens assembly (or possibly a curved, imaging mirror) that projects an image of a real object onto a drawing or painting surface. This toy does not project any images.

[Jonathan Townsend]

the retina is a surface.
the eye can be thought of as a camera obscura.

agreed, that ad reminded me of the drawing as advertised in old comic books.

[Dustin Stinett]

This toy does not project any images.

Yes, it does. It says that it does. It even uses those words ("projects" and "reflects") it its descriptions. Furthermore, the Pepper's Ghost image is in three dimensions. This is in two dimensions on a flat surface--just like camera obscura (http://en.wikipedia.org/wiki/Camera_obscura : "The image can be projected onto paper, and can then be traced to produce a highly accurate representation."). That fact alone completely sets this apart from Pepper's Ghost.

[Jonathan Townsend]

There's a video link on the ad with a moment viewing through the eyepiece to see the doubled image of paper and target object.

http://www.youtube.com/embed/9DBD7wTp3cw?autoplay=1

reflects image onto (view of) paper.

[Jim Riser]

This is nothing new. In my youth such things were made from squares of wood, wooden dowels, and a small angled piece of glass mounted within one of the wooden blocks. The reflecting glass need not be very large if it is close to the eye. On the old ones you looked into a hole in the top wooden block and your eye was probably no more than 1/2" from the angled glass.

There was a movie released a year ago or so based upon such a device and a famous painting. I can not recall which painting at the moment. Bill Mullins will probably know
Jim

[GlennWest]

Despite the ad copy, the image isn't projected. If it were projected, you wouldn't need the viewer.

[John Signa]

Glenn is correct in that there is no projection. Check out the video at :30 when overhead view of drawing in action... no projected image on the paper.

This is a variation of a camera lucida. http://en.wikipedia.org/wiki/Camera_lucida.

[Bill Mullins]

John is correct that the Sketch Wizard is a camera lucida. "In the simplest form of camera lucida, the artist looks down at the drawing surface through a half-silvered mirror tilted at 45 degrees. " It is optically equivalent to Pepper's Ghost (with the possible exception of an eyepiece that inverts the mirror-flipped image).

This toy does not project any images.

Yes, it does. It says that it does. It even uses those words ("projects" and "reflects") it its descriptions.

Rather than say that a toy manufacturer would LIE to separate a child's parents from their money (see: X-Ray Specs, Sea Monkeys, etc.), I'll generously suggest that they are using the word "project" in a very haphazard fashion. But they are wrong -- there is no projection (in the optical sense) going on here, as there is in a camera obscura.

Furthermore, the Pepper's Ghost image is in three dimensions. This is in two dimensions on a flat surface--just like camera obscura (http://en.wikipedia.org/wiki/Camera_obscura : "The image can be projected onto paper, and can then be traced to produce a highly accurate representation."). That fact alone completely sets this apart from Pepper's Ghost.

Their demonstration of the toy only is using two dimensions on a flat surface -- but it would work in 3D just as well (the language on the box evens says so "Draw . . . 3-D objects"). Put a matchbox car where the iPad sits, and some modeling clay where the drawing is made. You could use the same device to assist in shaping the clay into the form of the car. And while you are looking through the viewer, your hands will appear in 3-D (at least, to the extent anything does while you are looking at it with only one eye).

The partially reflective mirror is the important optical element, and it is the same optical element that is in PG. A camera obscura directs light from the object being painted through a lens (key point) to make an image on the paper. The artist then traces over the real image (term of art in optics) to make a picture. There has to be a lens. In this toy, the light doesn't go from the object to the paper and there is no real image. You are looking at a virtual image (term of art in optics) of your drawing of the image, it is overlaid on the object, and you try and make them match.

"Image" and "project" have specific technical meanings that the Crayola people are handwaving around here.


Jim -- the movie you are thinking of is "Tim's Vermeer". There are a couple of threads on it in the Forum over the last year. It's an excellent movie and well worth seeing. Tim Jenison didn't use a camera obscura in it; what he used was more like a camera lucida. The film talks about the differences between the two, and what his optical device is. Here is some speculation that the whole film is a hoax by Penn and Teller (he later agrees that it isn't, but it's still interesting to read).

GlennWest -- the viewer is for: making sure your eye is in the right place relative to the mirror, original, and copied drawing; and for (possibly) correcting the left-right (or up-down) flip that a mirror gives.

[Jim Riser]

Since a camera obscura was mentioned (though not the principle behind the toy), I will note that there used to be a wonderful camera obscura at the Garden of the Gods in Colorado Springs. You went into a building with a 10 foot diameter viewing screen about waist high. The roof mounted 13' focal length lens focused a beautifully clear "high res" image onto this screen. The view could be changed to project 360 degrees of colorful Colorado scenery. This was magical! The optics were superb.

In the 1980's, I believe, it was dismantled and the building razed. Whereabouts of the camera today is a mystery. There was also one at Lookout Mountain - also lost.

These cameras were similar in some ways to a periscope in that the top of the camera had a mirror which could be rotated 360 degrees. This top mounted first surface mirror reflected the light into the projection lens. Having played with lenses and mirrors since childhood, seeing the Colorado Springs camera obscura was of primary importance. It was well worth the visit.
Jim

P.S. Here is a rough idea of the facility:
http://www.geog.ucsb.edu/~jeff/115a/his ... bscura.gif
http://www.guillaumedorne.com/wp-conten ... ECTION.jpg
http://www.aip.org/history/newsletter/s ... ics_lg.jpg
http://web.up.ac.za/sitefiles/Image/48/ ... btable.jpg
http://media-cdn.tripadvisor.com/media/ ... bscura.jpg
http://www.rmg.co.uk/whats-on/exhibitio ... bscura.jpg
http://web.comhem.se/dagurre/CO-1lens.jpg

And here is the Colorado Springs camera:
http://brightbytes.com/cosite/coimages/GOG2.jpg

[Richard Kaufman]

There is a beautiful camera obscura at Tokyo DisneySea.

[John M. Dale]

If you're ever in San Francisco:
http://www.giantcamera.com

JMD

[GlennWest]

GlennWest -- the viewer is for: making sure your eye is in the right place relative to the mirror, original, and copied drawing; and for (possibly) correcting the left-right (or up-down) flip that a mirror gives.

I was considering the mirror to be part of the viewer, but I gotcha. Thanks.

[Dustin Stinett]

I had never heard of a camera lucida until now, so thanks to John for that.

John is correct that the Sketch Wizard is a camera lucida. "In the simplest form of camera lucida, the artist looks down at the drawing surface through a half-silvered mirror tilted at 45 degrees. " It is optically equivalent to Pepper's Ghost (with the possible exception of an eyepiece that inverts the mirror-flipped image).

Yes, like a camera obsura and lucida, the image must be flipped to be seen upright. It does NOT have to be flipped in the Pepper's Ghost illusion. That's because neither of these are Pepper's Ghost!

I recommend reading Steinmeyer's Science Behind the Ghost so you can see why the camera lucida--which you now admit is what this thing is--is not Pepper's Ghost, which was my (and Richard's) point from the beginning.

[John Signa]

Actually, in Peppers Ghost, the image is reversed and the "ghost" needs to be reversed to take that into account. If the ghost is supposed to raise his right hand, the actor raises his right.

If you don't, you might wind up with ghosts waltzing in the wrong direction...

[Dustin Stinett]

It's a progressive group of 999 ghosts: the ladies are leading.
(And don't you mean that the actor raises his left hand?)

[John Signa]

Yes, I meant left/right, not right/right. I had one too many ginger ales after dinner.

[Daniel Z]

Perhaps not magic but quite magical. http://tinyurl.com/qyc6kaf
a contemporary photographers approach to camera obscura