Observations About Patterns

Your pumpkin can have four tones of natural color.

• Black - where nothing was carved away.
• White/Yellow - where everything was carved away.
• Light orange - remove the skin and some of the pumpkin meat. This is how very detailed lines are done.
• Dark orange - remove the pumpkin meat from the rear, leaving the skin intact.

Shape is typically more important than color; this means that you can obtain the best results with a pumpkin of high contrast.

Your patterns will always be the negative of the image you're trying to produce.

Simple patterns consist of solid shapes, with the areas around them cut out. This is exactly like how a shadow gets cast on the wall or even how something looks when there is a bright light behind it. Imagine someone behind a shower curtain; if this particular excercise doesn't help you, it's still fun to do.

More complex patterns consist of a back ground, which will be cut out, minus another pattern that is in the foreground.

All pattern shapes must be connected to the edge of the pumpkin, or, obviously, they will be disconnected and fall in the pumpkin.

To see where pieces should connect, squint at the pattern or redesign the pattern to show the same image from a different perspective.

Great patterns use light (cut out areas) for the moon, stars, fire, smoke, house lights, and evil looking eyes.

This areas of light can often convey the area in the negative space. Viewers will use Gestaultism to imagine where connecting lines go.

Patterns make high use of negative space.

The use of perspective adds to the illusion and helps patterns leap out of the pumpkin.

Exageration of a pattern's focal length gives character to the design.

For very complex images, like faces, they must be done very contrasty to enhance attention to areas of shape. Light areas should be cut out, dark areas should be left.

Casting Rear Projections

Patterns are smaller than front patterns.

Patterns are above the light source.

Making a Simple Pattern

Cut this pattern out

of this pumpkin

and you'll see this.

Adding a Foreground

Starting with this background

we can add this forground

and you'll produce this pattern

resulting in this carving.

Use a black and white image in Adobe Photoshop for the background and the foreground. Then use Image/Calculations. Source 1 should be the background image. Source 2 should be the foreground image. Select Invert for Source 2. Blending should be Add. And Result should be New Document.

This new document will be a Multichannel document, so you'll need to select the resulting document and goto Image/Mode/Grayscale to change the document type.

What's happening is that the background represents negative space that you will carve away. We then take the inverse of the forground image, which shows what you don't want to cut away, and we add that to the background. By adding, the pixels are summed, finding all the white areas where you shouldn't cut the pumpkin away on your pattern.

Adding more foreground objects is as simple as performing this process over and over again.

However, we might want some foreground objects to be negative space as well, and to complicate matters they might intersect with other negative spaces.

Using this image

another foreground object is added

points are whited out so that no white piece floats in the middle of a black piece.

Again the Calculations tool is used. The original image is Source 1. The new foreground object is Source 2. Source 2 should have Invert checked, and Blending is now set to Difference. Result should be set to New Document.

This takes the foreground object and does an exclusive-or on the original pattern. At points where the the images change from positive space to negative, we have to make sure all positive-space (uncut pumpkin) pieces are attached.

One this pattern is cleaned up

it looks like individual solid black pieces, with no white pieces in black

and it results in this pumpkin carving.

Example from Clip Art

The background will be uncut pumpkin, so we darken that. Anywhere there's white will be where light will shine through. (Note that when we make the pattern, the reverse will be true.)

Since we want the ghosts to be light, they can't have any facial features "floating" in the light. For now we'll remove their faces and come back to them later.

Ok, I just spent 20 minutes with the pencil tool coloring in areas. Here are the progressive steps to prove it.

 

Remember, since in our picture, white represents candle light, you can't have pieces floating in space. We use the opportunity to color in areas by the flames. Look under the handles, and you'll see the flame is all a cut out. We leave a little bit of the cauldren shape showing. The viewer's mind fills in the rest.

Now we attack the two dark spots in the flame. We simply connect them to other dark spots that look right. If we couldn't, we'd just erase them.

Too bad we can't keep the inside of the handles. Oh well, but what we can do is make the two parts of the handle distingished by making the uncut areas more prominent. We do this above and below where the handle attaches.

Now we make the dark part of the opening connected to the background. Well shaped narrow slits help define objects more than absolute detail. We also use this time to make the edges around the bubbles thicker, in the process deliberately eliminating some of the bubbles.

Now it is time to clean up the ghosts. We can use the background dots to divide the ghost into more shapes, making the pumpkin stronger. Notice the line gets thickened.

And boy did that look bad, although, technically, it would work. Backing up to step five and trying again. This time let's elminate the line.

We also filled in the hands that were in the foreground, and made connection points bolder, to hold the pumpkin together better.

All that's left are faces, if we want them. These will have to connect to the sides of the ghosts' faces.

They'll do.

Now we invert the picture to show us where to cut. It's a lot easier to trace around a small amount of black pieces than white. Plus we save toner in our printers.

Now that things are inverted, a quick double check is in order... are there any white areas floating in a black area? We can check by doing a black flood fill in the white area. If the whole image goes black, we're done. You might want to save before doing this.

Now it is just a matter of scaling this to fit our pumpkin.

Download this Ghost Pattern

Making a Pattern from a Photograph