Home Basic Knots Advanced Treatments Analysis Triangular Further Topics Sources Grids

# Knotwork Tutorial-Line Treatments

## Introduction

To this point we've been simply using black to cover up the construction marks (dots, circles, or diamonds at the grid points) and filling in the bands with colors.  The Celtic scribes certainly used this technique in the original manuscripts.   They also used many other techniques to decorate the bands.   Some of these are covered below.

## Band Width

Try increasing the circle diameters/diamond widths without changing the grid spacing to construct thinner bands, and making smaller circles/diamonds to help get wider bands.

 This pattern is from [Meehan2], originally from Durrow.  Here is the original grid size, and a band generated using this template. Here is a grid with larger diamonds generating a narrower band. This grid uses smaller diamonds and, consequently, wider bands.  Note that some spaces between bands disappear with wider band widths. Sometimes the bands will need to be adjusted to compensate for this effect.

## Band Edge Effects

Besides changing the width, bands themselves were often decorated.

 The band edges were often drawn in black, letting the background parchment show through. Bands often had lines or dots running down the middle... ...or two narrow bands running on the sides of the band. Finally, the knots were sometimes simply drawn with red dots alone against the parchment.

## Colors

Celtic work was incredibly colorful.   Some knots were light on dark (as most of the examples), but some were dark on light backgrounds.  Colored areas were used on the bands and in the middle areas (between the bands) as well.   Even if a band was continuous, often more than one color was applied.

# "Doubling" Interlace Patterns

"Doubling" can be considered a line treatment that forms a parallel double band from a broad interlace pattern; the two new bands do not cross except where the original broad band did.  This form of interlacing was quite popular with the scribes and was extensively used in Kells.

Original construction techniques (see [BainG]) involved building the original wide interlaced band, then converting the edges of these bands into new, narrow, parallel bands, then fixing up the interlacing.  This requires a lot of erasing and fixing.  Doubling can be supported with the cell structures we've been using by following the procedure below:

 1. Draw original pattern on double-sized cells compared to the desired final results.  This pattern is taken from [BainG] page 40, Plate E, and was originally from Kells.  I also used large (double-sized) diamonds to keep the ratio of band size to cell size fairly constant. 2. Build a set of "half-sized" cells between the original points.  I used smaller than half-size diamonds for band spacing here to reflect the Lindisfarne style of doubling.  See [BainI} pages 71-72 for further information and alternative construction techniques.  On the illustration, the new cell diamonds are in red and the new cell sides are in green. 3. Add interruptions to the new patterns based on the old: if the original template has a corner, add a smaller corner inside and a larger one outside (if possible); if the original template has a wall, add a new wall one smaller on the "inside" (towards the middle of the panel or border) and one larger on the "outside" (towards the edges of the panel or border); then add walls of single cell edge size to break up any further walls and keep the new strands/bands in parallel.  On the illustration, the new walls are in red 4. Interlace as usual. Curves will take a bit of extra planning in order to keep them parallel and a constant width.  In this example, the curves used could have been a bit smoother (i.e., larger radius)--this would have meant more adjustments in the corners, though... 5. Color the bands as desired.  The illustration is colored to show the continuity of the bands across the repeating, doubled pattern.

Also see other examples of doubling provided on the Celtic Art pages.