Pepper's ghost

Pepper's ghost is an optical illusion that takes place thanks to the technicalism used in it.

It is an illusion that generates a lot of attractiveness in the theater, houses of terror and magical acts, but, more than "magic", what entails is a technique.

The name of this illusion is given thanks to his inventor, scientist John Henry Pepper, although many attribute creation to others.

Well, It is a technique that was very novel in the 16th century, So it is also pointed out that the alchemist, philosopher, comediograph and Italian researcher Giovanni Battista della Porta is his real inventor.

Battista Della Porta is also attributed to invented "The Dark Chamber" and, in fact, has a book written in 1584 that is titled "Magic Naturalis", which includes a section where it explains how it can be seen in A dark room things that are not.

In any case, the works of Giovanni Battista could be classified as the first steps, not only towards the invention of Pepper's ghost, but also of the cinema itself.

Pepper's ghost: an illusion with technicalism

In many optical illusions we can find the explanation to it in different reasons; For example, in some illusions the explanation will be in our retina, while in another the perception will be responsible for making us see what we observe.

But, in the illusion of Pepper's ghost, although we are deceived, The explanation is found in the use of a technique.

It should be noted that, although Henry Pepper is the scientist who almost everyone considers the inventor of the illusion, next to him also worked another inventor called Henry Dircks.

In 1862, Dircks developed a proposal that consisted of a visual effect called PhantasMagoria, However, this idea did not have a good reception in the theaters, especially because of all the expenses it implied, since, in order to implement it, a complete transformation of the site was necessary.

But, Dircks did not give up his idea, but presented her to John Henry Pepper, who realized that the entire Dircks system could be modified by something easier.

So that the changes were implemented and the effect was shown in a scene of HAUNTED, of Charles Dickens, with results that were applauded by many.

Since then, Pepper is attributed to Pepper, although he tried to give the credits to Dircks. In any case, today everyone knows the effect with Pepper's ghost name, then, so has endured.

What is the visual effect of Pepper's ghost?

Pepper's ghost continues to be widely used, not only in horror houses, but also in the theater.

Indeed, the author Paula Rojas Amador, in her study on the Pepper ghost device: the intermediality and the presence effect, it emphasizes that this technique is precursor in the use of the virtual image in the scene, which opens a debate Today about the relationship between virtual and "real" presence in the theater.

But, beyond these discussions, Pepper's ghost is to apply a trick with a stage that, in turn, is divided into two rooms.

One of these rooms is visible to the public, while the other -subject to the side -remains hidden and is called Blue Room.

The "magic" of this trick, or rather technical, is that, Between these two rooms, there is a glass sheet, transparent film or plexiglass, which is what allows the reflection to be projected to the spectators. Of course, the angle in which this layer is placed must be necessary.

In addition, the crystal or sheet must be invisible, in the largest possible measures. Therefore, in many scenarios, the edge is simulated with a decoration, making many times it seems part of the same ground.

Likewise, It is important to have a light source, or "magic flashlight". Other details are equally relevant.

The actor who will give life to the ghost must be located under the stage and must be positioned behind a black background.

Under the platform there is also a technician, who is the one who works with the light source.

The lighting is vital for Pepper's ghost to be reflected; The space must be semi-obscure or dark.

In summary, You should always take into account the place where the spectators will be, The space under the stage, in which both the actor and the technician will be, and the luminosity.

All this mechanism will come into operation when the actor who plays the ghost is illuminated by the coach. At this time, what is produced is a ray of reflection in the sheet.

The movements must be careful about what you want to interpret. If the actor wants the right hand to look in motion, then it may be used to use the left, so that the right is the one that is projected on the reflective surface.

The actor should not wear any garment, but of white tone to help with the projection of the image. Some actors also use skeleton costumes.

Finally, it can be mentioned that This optical illusion can be seen thanks to the reflection and refraction of light.

Today, this technique continues to be improved and therefore more novel technologies have been used, such as hologram. But, the essence remains the same.

ILLUSION OF MACH BANDS

Bibliography

• Amador, p. R. (2017). Pepper's ghost device: intermediality and presence effect.  Arts Magazine, 28-44.
• Chaves Filho, G. (2020). "Pepper's Ghost": how to ensure/learn Physics Councils through UMA simple optics illuside.
• Miranda Silva, V. AND., Santos Almeida, M. W., Teixeira, J. M., & Teichrieb, V. (2014, November). Tridimensional Visualization Through Optical Illusion. In Proceedings of the 20th brazilian symposium on multimedia and the web(pp. 163-166).
• Rodríguez, a. R. M., Santana, e. R. TO., & Guerrero, I. TO. C. Holographic visualization.