November 22, 2012

Prevent image deformation of analog projector

Airbrush artists often project a reference image onto the surface on which they are airbrushing to trace the image with a pencil before they begin to spray. Many use an analog projector that radiates light on the image that is reflected by mirrors to a lens. Besides a flood of light, this lamp produces a lot of heat. This heat deforms the photo or printed reference image that gradually expands as a result of the energy induced to it. These deformations often show in the completed art work; most notable is that one eye is placed higher than the other. Tracing fast minimizes the image deformation but it almost always shows that an artist has been using a projector. There is a simple solution to this.

Glass plate supported by foam strips

I taped two foam strips to the side of a thick glass plate that I place on top of the projector as can be seen in the image below. Glass lets light pass through it, but it is an excellent isolator of heat. The space below the plate is filled with air which is an other isolator of heat. The photo or print of the reference image is placed on top of the plate. A book or an other flat bottomed, heavy object can be place on top of the photo or print to fixate it on one place.

Glass plate on projector

This set-up will allow the artist a lot more time to trace the image before it starts to deform. Having more time also means they can trace more detail without having to worry about deformation. The reference image of a Giger art work that I used as explained in my previous blog entry shows an example of the deformation by the heat generated by a projector. Take a look at the image of it below.

The eye on the right is placed higher

The image subject's left eye (the right one to the observer) is placed higher than the other one. Typically, artists start tracing the left eye, then other facial parts like the nose, mouth etc. and then the right eye. In the time it takes them to trace these parts the reference image expands due to the induced heat and the other eye moves away from where it was when the image was still at room temperature. Go ahead and google airbrushed portraits; you will see that many right eyes (from the observer's point of view) are sprayed a little higher than the left one ....

This oddity applies to analog projectors only. Digital projectors do not suffer from heat deformation. Nor does the light box projection method I described in an earlier blog entry. Happy tracing!