HoopsideConverting
How to convert a DST to PES — and why renaming the file fails
You bought a design in DST and your Brother wants PES. The fix is a real conversion — and the thing that looks like a fix, renaming the file, is what breaks it.
Why renaming cannot work
An embroidery format is an encoding, not a label. DST stores each movement as a small relative step; PES wraps a different stitch block in its own header with a thread list. Renaming roses.dst to roses.pes changes three letters and leaves every byte inside untouched. The machine opens it, finds a header it does not understand, and refuses — or worse, reads it as garbage.
What a real conversion has to do
Three things, and the third is the one cheap converters skip.
- Decode the source. Turn the DST's relative steps back into an ordered list of stitches, jumps, trims and colour changes.
- Rebuild the file in the target format, with whatever header, thread table and end marker that format requires.
- Re-encode the stitches within the target's limits. Every format caps how far a single command may travel, and the caps are different.
| Format | Longest single command |
|---|---|
| DST | ±121 units |
| EXP, JEF | ±127 units |
| XXX | ±124 units |
| VP3 | 255 units |
| PES, PEC | ±2047 units |
Units are tenths of a millimetre. So a single stitch that is perfectly legal in a VP3 design can be more than twice what a DST command can express. A converter that ignores this either fails outright or silently writes a shorter stitch — which is a design that stitches wrongly, and you only find out with fabric in the hoop.
Done properly, an over-long stitch is split into a run of legal ones along the same path. The needle goes to the same places; the file just says so in smaller words.
Converting on your phone
- Open the design in Hoopside.
- Tap Convert and pick the format your machine reads — PES for Brother and Babylock, JEF for Janome, VP3 for Husqvarna and Pfaff, EXP for Melco and Bernina, XXX for Singer.
- Choose where to save it. The original is never touched.
If you have a whole folder to move to a new machine, convert the folder in one go rather than file by file — and check the list of files it could not do, which a good batch converter will name for you instead of quietly skipping.
What conversion cannot fix
Colour, quality and size
Colour. Converting a DST to PES does not recover thread names the DST never held. The new file will have a thread list, but its colours are stand-ins.
Quality. A badly digitized design is still badly digitized in another format. Conversion moves stitches; it does not improve them.
Size. Converting does not resize. A 200 mm design converted to PES is still 200 mm and still will not fit a 100 × 100 mm hoop.
What "re-encoding" means, concretely
Take one stitch that travels 18 mm. In VP3 that is a single legal command. In DST, where the cap is about 12 mm, it is not — so a correct converter emits two commands along the same line, each within the cap, landing the needle in exactly the same place. The design is unchanged; the file simply describes it in smaller steps.
The same is true of long jumps between areas of a design. Get this wrong and the stitches land somewhere else, which on fabric means a line across your work.
Colour, converting in both directions
Converting from DST to PES gives you a file with a thread table, but the names in it were not in the DST — they are stand-ins, because a DST had nowhere to record them. Converting from PES to DST discards names that really were there. Neither is a bug; it is what the formats can hold.
The colour stops survive in both directions, which is the part that matters at the machine: it still pauses in the right places and the same number of times.
How to check a conversion actually worked
Open the converted file — not the original — in a viewer and compare four things.
- Size should be identical, to within a tenth of a millimetre.
- Colour stops should be the same number, in the same order.
- Stitch count may rise slightly, because splitting one long stitch makes two. It should never fall.
- The shape should look the same. A design that has shifted or scaled is a failed conversion, however plausible the numbers.
If all four match, the conversion is sound. If the stitch count dropped, the converter truncated something and the file is not safe to stitch.
Keep the original. Convert to a new file rather than over the top of what you bought. If the machine ever refuses the converted version, you want the source to try again from — and if you later buy a different machine, you will want it again.
Related
- Embroidery file formats explained — Which machine reads which format, what each one stores, and which of them carry colour at all.
- What is a JEF file, and how do you open one? — Janome's format: what it stores, how to view one, and how it differs from PES and DST.
- Why your machine rejects an embroidery file — Six reasons a design will not load, in the order worth checking.
Convert a design for the machine you own
Hoopside converts a design to DST, PES, JEF, VP3, EXP or XXX, re-encoding the stitches for the format you pick rather than just renaming the file. Viewing every design is free; converting is a one-time unlock.
