Why is fabric so hard to judge from a photo?
A camera captures an outline sharply. It captures the way a fabric moves, weighs and behaves only indirectly, through hints that most people never learn to read.
That imbalance runs through the whole of online shopping. Two dresses cut to the same pattern, one in a heavy crepe and one in a thin polyester, are nearly indistinguishable in a product shot and are plainly different garments in your hands. Learning the hints is what closes that gap before you have paid for it.
What can you actually read about fabric in a photo?
Ignore the fibre for a moment. These four are visible in almost any photograph, and together they narrow the possibilities a long way.
- Drape. How the cloth falls when nothing is holding it. Look at the hem and at the fabric between the arm and the waist. Stiff cloth makes angles, soft cloth makes curves.
- Sheen. How it takes light. Natural fibres spread a highlight softly across a fold. Cheap synthetics put a hard white line along the top of one and nothing either side of it.
- Wrinkle. Where and how it creases. Linen creases sharply and at random. Wool barely creases at all. Polyester holds almost nothing, which is its own kind of clue.
- Weight. Whether the garment hangs from the shoulders or clings. Heavy cloth stands away from the body and holds a shape after the wearer has moved.
Look at the folds rather than the flat areas. A flat panel of cloth tells you its colour. A fold tells you what it is.
What is drape, and why does it matter most?
Of the four, drape carries the most information, because it is the thing the designer was choosing when they picked the fabric.
Look at the hem when the wearer is standing still, and at the cloth between the arm and the waist. Stiff fabric makes angles: it breaks into flat planes with clear edges between them. Fluid fabric makes curves: it collapses into rounded folds that run into each other.
A garment designed around fluid drape and then made in a stiffer cloth reads as boxy and cheap, and it is the single most common way a copy fails. If the version you are looking at makes angles where the original made curves, it is a different garment.
How does the shine on a fabric tell you the price?
Every fabric reflects light, and how it does so is close to a fingerprint. Silk and good synthetics spread a highlight gradually across a fold, so the bright area has soft edges and the colour stays believable through it.
A cheap synthetic does the opposite. It puts a hard white streak along the top of a fold with a sharp edge and almost no transition, and the colour disappears inside the highlight. Once you have noticed this you cannot stop noticing it, and it is the fastest way to sort a rail of satin dresses by price without reading a single tag.
Matte fabrics carry the same signal in reverse. A good matte cloth shows subtle variation across a surface, while a poor one photographs as one dead flat colour with no life in it at all.
Is denim a fibre, a weave or a garment?
A lot of confusion here comes from three different kinds of word being used as though they were the same kind.
Fibres are what the thread is made of: cotton, wool, linen, silk, polyester, viscose, elastane. This is what a composition label lists.
Weaves and knits are how the thread was turned into cloth: satin, twill, poplin, jersey, rib, crepe. These describe structure and say nothing about the fibre, which is why a satin dress can be anything from luxurious to unwearable.
Finishes are what was done afterwards: brushed, washed, sandwashed, coated, mercerised. These change how a fabric feels and looks without changing what it is.
Searching gets much better once you use the right kind of word for what you actually care about. If the drape is the point, search the weave. If durability is the point, search the fibre.
How do you read a composition label?
A composition label is a list of percentages, and you only need two things from it.
First, which fibre holds the majority, because a blend behaves mostly like its largest component. Second, whether there is any elastane at all, because that single detail changes how the garment is meant to fit and therefore which size you should order.
Everything else is refinement. A few per cent of one fibre added to another usually exists to fix a manufacturing problem rather than to change how the garment wears.
What does the care label tell you about the fabric?
Care instructions are the maker telling you, in advance, what the fabric will not survive. Read them before buying rather than after.
Dry clean only means water will damage it: shrinkage, dye movement, or an internal structure that will collapse. That is expected on tailoring and on silk. On a casual piece you intended to wear weekly, it is a real running cost.
Wash cold and do not tumble usually means shrinkage is likely. Wash separately means the dye is not fully fixed and will move onto something else at least once. Each of these is a fact about the garment that the product description was never going to volunteer.
How do you recognise each fabric in a photo?
Each chapter takes one material, gives the visual tell that identifies it in a photo, and lists the words a shop is likely to have typed in the listing. Nothing appears in a chapter here unless it can be read from a picture.