Why resolution matters for giclée prints (and how to get it right)

You've made something you're proud of, a painting, a photograph, a digital illustration, and you want it printed large, rich and gallery ready. More often than not, the single thing that decides whether that's possible is resolution.

It's also the thing most people find confusing, and the most common reason we have to go back to a customer and ask for a better file. Once you understand it, though, it's simple to get right, and it comes down to one number and a bit of easy arithmetic.

What "resolution" really means for printing

A digital image is a grid of tiny coloured squares called pixels. When we print, those pixels are spread across the paper. The more pixels packed into each inch of print, the finer and sharper the detail.

We measure that as ppi (pixels per inch). For fine art printing, the number that matters isn't the "dpi" tag buried in your file's settings. It's how many pixels you actually have relative to the size you want to print. That's your effective resolution, and it's what we look at first.

The target: 300 ppi at final size

For giclée printing on our Canon imagePROGRAF, the sweet spot is 300 ppi at your final print size. At 300 ppi, every bit of detail your eye can resolve at a normal viewing distance is there on the paper, crisp edges, smooth gradients, no softness or blockiness.

Work it out with one simple sum:
Effective ppi = long edge in pixels ÷ long edge in inches

So a file that's 3,000 pixels along its longest edge gives you 300 ppi at 10 inches (3,000 ÷ 10 = 300). Print that same file bigger, and the pixels have to stretch further apart, so the effective resolution drops:

Same 3,000 px file, printed at…	Effective resolution	Result
10" × 8"	300 ppi	Perfect - full detail
15" × 12"	200 ppi	Very good
20" × 16"	150 ppi	Noticeably soft
30" × 24"	100 ppi	Visibly pixelated

Nothing about the file changed. Only the size did. The bigger you go, the thinner those pixels are spread.

This is also why a photo can look pin-sharp on screen and still disappoint on paper. A typical computer monitor shows only around 100 pixels per inch, a third of what a fine print needs and it usually displays your image shrunk to fit the screen rather than at full size. So you're looking at far fewer pixels than the print will actually demand. The screen is forgiving in a way the paper isn't.

How big can my file print?

Turn the sum around. Take the size you want, multiply each side by 300, and that's roughly the pixel dimensions you need:

• A 12" × 8" print wants about 3,600 × 2,400 px
• A 24" × 16" print wants about 7,200 × 4,800 px
• A 40" × 30" print wants about 12,000 × 9,000 px

Phones are worth a special mention, because their headline megapixel numbers are misleading. A phone sold on its 48-megapixel or even 200-megapixel camera almost always saves a far smaller file by default, usually around 12 megapixels (roughly 4,000 × 3,000 pixels), sometimes 24 on newer models. It does this on purpose, merging groups of pixels together to produce a cleaner, less grainy image. That 12-megapixel photo prints beautifully up to about 13 × 10 inches at 300 ppi. Ideal for smaller prints, but short of a large piece.

If you want to print bigger from a phone, look in your camera settings for a "high resolution," "full resolution" or RAW mode, which saves the sensor's full detail. Those files are much larger to store and send, but they give you the pixels to work with.

We can print any size up to 43 inches wide, and considerably longer than that for panoramic work so it's rarely the printer that's the limit. It's usually the pixels.

"Can't you just upscale it?"

Sometimes, a little. Upscaling software including the newer AI based tools can enlarge an image and tidy up the edges. But it's important to understand what it's really doing. It's inventing new pixels based on the ones around them, not recovering detail that was never captured in the first place. It can smooth, but it can't genuinely sharpen something that isn't there.

For a modest stretch it can be worth trying, and we're happy to judge the result together on a proof before committing to a full size print. It's just no substitute for starting with a properly sized file.

The canvas exception

Canvas is more forgiving than fine art paper. The texture of the weave naturally masks a degree of softness, so on the right image we can sometimes get a good result from around 180 ppi. It genuinely depends on the picture, though, so we'll always take an honest look and tell you what we think rather than promise it blind.

Working from an original rather than a file?

If your artwork exists as a physical piece, an original painting, drawing or photograph, you don't need to worry about any of the above. Our in-house scanning service captures work at up to 1,200 ppi, more than enough to reproduce it at large sizes with every brushstroke and texture intact. 

The simple way to be sure

You don't have to do the maths yourself. Email your file, and the size you'd like it printed, to info@saxonprint.com we'll check the effective resolution, tell you the largest size it'll print well at, and give you a quote. Or, if you already know your file is up to it, you can order directly through the website.

Not sure which paper suits your work, or want to see the quality before you commit? Order our giclée sample pack, or take advantage of our discounted A4 proof to see your own image on your chosen stock first.

We're a small studio in Winchcombe, near Cheltenham in the heart of the Cotswolds, and we treat every print with the care it deserves. Get the resolution right, and there's very little between your artwork and a print that does it full justice.