Raster vs vector art: which should you use for products?

Raster or vector is one of those choices that feels academic until a design lands on the wrong product and either turns to mush or loses everything that made it worth printing. The two formats aren’t rivals competing to be “better” — they’re built on completely different ideas about what an image is, and each is genuinely the right tool for some jobs and the wrong one for others. Understanding the difference takes about five minutes and saves a lot of reprints. Here’s how each works, what file types belong to each, and how to pick for a given product.

Pixels versus maths: two ways to describe a picture

A raster image is a grid of coloured squares. Each pixel stores one colour value, and the picture exists only as that fixed mosaic — a 2000×2000 image is exactly four million little decisions about colour, no more and no less. Photographs are inherently raster because a camera sensor samples light at a grid of points. The format excels at continuous tone: subtle gradients, soft shadows, the millions of slightly different colours in a face or a sky.

A vector image stores no pixels at all. Instead it holds mathematical instructions: “draw a path from this point to that one, curving by this amount, fill it with this colour.” Because the shapes are equations rather than samples, the software can re-draw them at any size on demand. A vector circle is the idea of a circle, computed fresh to fit whatever canvas you give it — a postage stamp or the side of a van — with edges that stay mathematically perfect at both.

The core difference: resolution-dependence vs infinite scalability

This is the distinction that matters for product work. A raster image is resolution-dependent: it has a finite number of pixels, and asking it to fill a bigger space means each pixel must grow. Enlarge it far enough and the squares become visible — the dreaded blocky, blurry result — because there’s no extra detail hiding inside the file to reveal. The software can only stretch or interpolate what’s already there.

A vector image is resolution-independent. Scale it up and the maths simply recomputes the same crisp paths at the new size; there are no pixels to enlarge and nothing to go blurry. The very same SVG can print sharp on a business card and a billboard. That single property — scale once, use everywhere — is why brand assets that must appear at wildly different sizes are almost always built as vectors.

The file types that belong to each

Knowing which family a file belongs to is half the battle, because the extension usually gives it away:

• Raster formats: PNG (lossless, supports transparency — great for clean graphics and logos exported flat), JPG/JPEG (lossy compression, small files, ideal for photographs but no transparency), TIFF (lossless, high-quality, the workhorse for professional photo printing), and PSD (layered Photoshop working files).
• Vector formats: SVG (open, web-native, text-based and easy to edit), AI (Adobe Illustrator’s native working format), EPS (a long-standing print-and-exchange standard), and PDF (which can carry vector paths, raster images, or both — the common safe handoff for print).
• A catch worth knowing: a PDF or EPS can contain a raster image embedded inside it. The wrapper being a “vector” format doesn’t make a photo inside it scalable — the embedded pixels still have a fixed resolution.
• Another: exporting a vector to PNG or JPG “flattens” it to pixels at one fixed size, discarding the scalability. Keep the editable vector master; treat the raster export as a one-size copy.

When each format suits a product

The rule of thumb follows directly from how each works. Vector is the home of anything built from clean shapes and defined edges: logos, monograms, icons, line art, badges and — crucially — typography. Text rendered as vector stays razor-sharp at any size and prints with hard, clean edges, which is why a slogan, a brand mark or a single-colour illustration belongs in vector wherever possible. It also produces small files for simple shapes and recolours cleanly.

Raster is the home of tonal richness. Photographs, digital paintings, watercolour and gouache scans, and detailed illustration full of texture and gradient simply can’t be expressed as a handful of flat-filled paths — they need the millions of independent colour values only a pixel grid provides. Forcing such artwork into vector (by auto-tracing) usually flattens its subtlety into posterised bands. For these pieces, a high-resolution raster file at the right print size is exactly what you want.

This is the heart of how Realform thinks about creators’ work. A painter’s artwork is raster by nature — every brushstroke and gradient lives in the pixels — and that finished file is the creator’s, full stop. Realform’s agents compose that existing artwork onto products at the correct size and resolution; they never auto-trace it into a flat vector, never regenerate it, and never “stylise” it into something new. The format stays faithful to what the artist made, and the AI’s job is the production around it, not the picture itself.

Converting between the two (and why it isn’t symmetrical)

Converting vector to raster is easy and lossless-in-spirit: you “rasterise” by rendering the paths to a pixel grid at a chosen resolution. Pick a size big enough for the job and the result is faithful — you’re just freezing the maths into pixels at that scale. The only catch is that you lose future scalability, so always keep the vector master.

Going the other way — raster to vector — is fundamentally harder and often disappointing. Auto-tracing software guesses at paths to approximate the pixels, which works tolerably for simple, high-contrast line art (a black logo scanned from paper) but produces garbage for photographs: it can’t meaningfully reduce a face to flat-filled shapes, so you get muddy blobs or thousands of jagged fragments. There’s no mathematical structure to recover because none was ever there. If you need a logo as vector, redraw or rebuild it; don’t expect a trace of a photo to behave like a true vector.

A quick decision guide

• Logo, icon, monogram, badge, single-colour mark → vector (SVG/AI/EPS/PDF).
• Typography or a text-led design that must stay crisp at any size → vector.
• Photograph or product shot → raster (TIFF for print masters, JPG for delivery).
• Painting, detailed or textured illustration, anything with rich gradients → raster (high-resolution PNG or TIFF).
• Need one asset usable from business card to banner → vector if the artwork allows it; otherwise a raster master sized for the largest use.
• Handing off to a printer and unsure → a PDF is the safest container, but make sure any embedded raster is high enough resolution for the final size.