Reducing the number of colours in a chart

What you need

• Your photo or chart open in the converter
• The key, with the stitch count of each thread

Confetti, or why less is more

Stitchers call single stitches of one colour among another “confetti”. Each one means starting a thread, making one or two stitches, and ending it again. On a chart covered in them you spend more time changing thread than stitching, and it is one of the most common complaints from beginners who bought a chart made from a photo.

Three signs never lie: a key of more than 30 colours, most of them used for fewer than 20 stitches; a ten-by-ten block holding eight different colours; near-identical threads side by side in the key.

How many threads to keep

There is no single right number, but there are ranges that work. DMC's own photo-chart service tops out in practice at 20 to 35 colours; for a first piece, far fewer will do.

Tip. The size of the chart matters as much as the subject: under 50 stitches wide, stay under ten threads. The guide to choosing the size of a chart explains why.

Lower the slider, then look

In the converter, the “Thread colors” setting runs from 2 to 35. The safest method is to go down until something important disappears, then go back up a notch.

1. Start high, say 20, and look at the chart beside the photo.
2. Lower it two or three threads at a time. The chart redraws each time.
3. Stop as soon as a detail that matters goes: the glint in an eye, the shadow that gives a cheek its roundness, the stem of a flower.
4. Go back up one or two threads. That is your number.

Merge threads that look alike

The key gives the stitch count of each thread. A thread used for only a few stitches, beside a near-identical neighbour, is the first to replace. Tap it in the list to see where it falls on the chart, then use the wheel to swap it for its neighbour: its stitches take the other's colour.

Whites are the classic case. White, B5200, which is bluer and brighter, and the warmer Ecru and 3865 only really differ laid side by side. A chart rarely needs more than two of them. The same goes for very light beiges such as 739 and 738, or the greys from 762 to 415.

Each thread has its page in the colour chart, with its eight nearest shades: the right place to see whether two references are both worth keeping.

Keep the stitches that do work

Not every single stitch has to go. The glint in an eye, a star in a night sky, a cat's whisker, the speck of light on a cherry are confetti on purpose, and they are often what makes the piece. Ask of each one: if I take it out, will I notice? If not, it goes.

Removing the background frees colours

A busy background takes threads for itself. With “Remove the background”, the subject gets every colour back, and you can often drop three or four threads without losing anything. If the background has to stay, simplify it before converting: the guide to preparing a picture shows how to blur it.

Stitch with the threads you have

“Use my own threads” limits the chart to the references you enter, or to those in your thread box if you have an account. It is the most radical way to cut the palette: the photo is translated with your stash and nothing else. For a result that holds together, pick those threads as a palette, with the guide to choosing your DMC colours.

Tidy up by hand

A few pointless single stitches always remain. “Edit by hand” opens the chart in the pattern maker, where you repaint them in their neighbours' colour, square by square. Ten minutes of tidying saves dozens of thread starts.

Tip. If some confetti is still there when you stitch, do not cut the thread after every stitch. On the back, a thread can travel three or four squares without showing; beyond that, end it, as the guide to starting and ending a thread explains.

• Next guide: Choosing your DMC colours: building a palette
• All guides