{"course":{"slug":"vector-and-print","title":"Vectors, Logos and Things That Get Printed","url":"https://addaly.com/learn/vector-and-print","level":"beginner","track":"create"},"lesson":{"slug":"large-format-and-distance","title":"Signage, viewing distance and the seams","url":"https://addaly.com/learn/vector-and-print/large-format-and-distance","position":73,"of":73,"minutes":8,"answer":"Large-format resolution is set by viewing distance (20 to 40 ppi at full size for a hoarding seen from 30 m) and the constraints that actually decide the design are where the panel seams fall.","keyIdea":"Large-format resolution is set by viewing distance (20 to 40 ppi at full size for a hoarding seen from 30 m) and the constraints that actually decide the design are where the panel seams fall, the hem and eyelet allowance, and cap height of about 25 mm per 3 m of viewing distance."},"body":{"format":"markdown","text":"## The resolution question answered properly\n\n\"What resolution for a hoarding?\" is the wrong question, and the answer people give (300 dpi) is wrong by an order of magnitude.\n\nWhat matters is the **angular** size of a detail at the viewing distance. The working figures used in the trade:\n\n- Viewed at **1 m** (an exhibition panel, a poster): 150 ppi at final size.\n- Viewed at **3 to 5 m** (a shop board, a pull-up banner): 100 ppi.\n- Viewed at **10 m** (a building sign): 50 ppi.\n- Viewed at **30 m or more** (a hoarding, a motorway sign): **20 to 40 ppi** at full size.\n\nA 6 × 3 m hoarding at 30 ppi is 7087 × 3543 pixels. That is an ordinary camera file. The image everybody panics about is usually already sufficient.\n\nThe other way to say it: build the artwork at **one-tenth scale at 300 ppi**, which is the same number of pixels and a document your machine can handle.\n\n**Vector artwork has no resolution at all** and needs none of this. Only placed photographs do.\n\n## Legibility, and the rule with its caveats\n\nThe commonly quoted rule is **25 mm of capital height for every 3 m of viewing distance**: roughly one inch per ten feet. It comes from readability research and it is a floor for *legibility*, not a target for *impact*.\n\nThe caveats matter:\n\n- It assumes good contrast, a clear typeface and a stationary reader.\n- A **moving** reader needs considerably more. Traffic signage standards use far larger letters for exactly this reason.\n- A **condensed** face at the same cap height is harder to read.\n- **Reversed** type on a dark ground needs a slightly heavier weight at distance.\n\nSo: 25 mm per 3 m as a minimum, doubled for anything read from a moving vehicle, and checked by printing a sample letter and walking away from it. That last test takes five minutes and settles every argument.\n\n> Figure: How big a capital has to be. Line chart of Minimum cap height, mm against Viewing distance, metres: A standing reader (3, 25) (10, 83) (20, 167) (30, 250) (50, 417); Read from a moving vehicle (3, 50) (10, 167) (20, 333) (30, 500) (50, 833). Twenty-five millimetres of cap height for every three metres, which is a floor for legibility rather than a target for impact. It assumes good contrast, a clear face and a reader standing still; double it for anything read from a moving vehicle.\n\n## Panels and seams\n\nA hoarding is almost never one piece. Flex or vinyl comes on rolls of a limited width (commonly 1.6 m, 2.2 m or 3.2 m), so a 6 m banner is printed in panels and welded or overlapped.\n\n**Find out where the seams fall before you design.** Then keep off them:\n\n- Faces, especially eyes and mouths.\n- The logo.\n- Any text.\n- A precise geometric alignment that will visibly step at the join.\n\nTwo or three questions to the fabricator (roll width, seam position, overlap or weld) and you can place your elements in the panels rather than across them.\n\n## Substrates and finishing\n\n- **Flex / PVC banner**: the standard hoarding material. Needs **eyelets** every 500 mm or so and a **hem** (a folded, welded edge) for strength. Add **100 mm of extra material** all round for the hem, and keep artwork out of it.\n- **Mesh**: perforated, for windy sites and building wraps. Passes wind, so the image is seen through holes and loses about 30% of its density; design for it.\n- **Self-adhesive vinyl on ACP**: shop boards.\n- **Foam board / Sunboard**: interior only, light, cheap.\n- **Backlit flex**: translucent, for lightboxes. Colours behave differently with light passing through them; ask for a sample lit from behind.\n\n## The things that are not your job but are your problem\n\n- **Wind loading** on a large sign is an engineering question and a legal one in many places. Not your decision, and worth asking about, because a sign that comes down is everybody's problem.\n- **Planning permission and local rules** on sign size, illumination and position exist in most jurisdictions and vary enormously. Ask the client whether they have it; do not advise on it.\n- **Installation access**: a sign 8 m up needs a ladder, a scaffold or a cherry picker, and the cost of that can exceed the sign.\n\n## What to send\n\n1:1 if the RIP takes it, otherwise 1:10 with the scale in the filename. Vector for everything except photographs. CMYK, with a profile if the shop names one. Bleed of **25 to 50 mm** rather than 3 mm, because large-format trimming is coarser. Hem and eyelet allowance marked on a separate layer. And a low-resolution reference JPEG so the operator can see what it should look like."},"check":{"question":"A 6 × 3 m hoarding is to be printed from a photograph that is 7000 × 3500 pixels. The designer refuses the image as too low resolution and asks the client for a larger file. Is this correct?","options":[{"text":"No: 7000 pixels across 6 m is about 30 ppi, which is normal for a hoarding read from 30 m.","correct":true},{"text":"Yes: any printed image below 300 ppi at final size will show visible pixellation regardless of distance.","correct":false,"tempting":"The 300 ppi figure applies at reading distance. At 30 m the eye cannot resolve anything close to that level of detail."},{"text":"Yes, but only because large-format RIPs upsample to 150 ppi internally and the source must exceed that figure.","correct":false,"tempting":"RIPs do not impose a source resolution floor, and internal upsampling adds no detail that would justify rejecting the file."},{"text":"No: the file should instead be resampled up to 150 ppi at full size before printing, which is what the RIP expects.","correct":false,"tempting":"Reaches the right verdict on the refusal and then prescribes an upsample that adds interpolated pixels and no detail."}]},"prev":{"slug":"garment-printing-processes","title":"DTF, DTG, sublimation and heat transfer","url":"https://addaly.com/learn/vector-and-print/garment-printing-processes"},"next":null,"authorship":"Founder and series editor: Dr Mustafa Mun. Written by AI models to a written standard. Exam keys checked blind by a second model: 3,665 of 3,666 agreed. Academic review invited.","review":{"status":"Draft, open for academic review"},"cite":"Addaly (2026) 'Signage, viewing distance and the seams', in Vectors, Logos and Things That Get Printed. Edited by M. Mun. Addaly. Available at: https://addaly.com/learn/vector-and-print/large-format-and-distance (Accessed: 13 October 2026).","licence":{"name":"CC BY-NC-SA 4.0","url":"https://creativecommons.org/licenses/by-nc-sa/4.0/"},"reader":{"schema":1,"title":"Signage, viewing distance and the seams","courseTitle":"Vectors, Logos and Things That Get Printed","module":{"index":8,"slug":"machines-that-make-things","title":"Machines that cut, stitch and burn"},"answer":null,"keyIdea":"Large-format resolution is set by viewing distance (20 to 40 ppi at full size for a hoarding seen from 30 m) and the constraints that actually decide the design are where the panel seams fall, the hem and eyelet allowance, and cap height of about 25 mm per 3 m of viewing distance.","hero":{"kind":"figure","figure":{"t":"figure","label":"Figure","figure":{"type":"line","title":"How big a capital has to be","series":[{"label":"A standing reader","points":[[3,25],[10,83],[20,167],[30,250],[50,417]]},{"label":"Read from a moving vehicle","points":[[3,50],[10,167],[20,333],[30,500],[50,833]]}],"xLabel":"Viewing distance, metres","yLabel":"Minimum cap height, mm","caption":"Twenty-five millimetres of cap height for every three metres, which is a floor for legibility rather than a target for impact. It assumes good contrast, a clear face and a reader standing still; double it for anything read from a moving vehicle."},"alt":"Figure: How big a capital has to be. Line chart of Minimum cap height, mm against Viewing distance, metres: A standing reader (3, 25) (10, 83) (20, 167) (30, 250) (50, 417); Read from a moving vehicle (3, 50) (10, 167) (20, 333) (30, 500) (50, 833). Twenty-five millimetres of cap height for every three metres, which is a floor for legibility rather than a target for impact. It assumes good contrast, a clear face and a reader standing still; double it for anything read from a moving vehicle."}},"blocks":[{"t":"h2","id":"the-resolution-question-answered-properly","runs":[{"text":"The resolution question answered properly"}]},{"t":"p","runs":[{"text":"“What resolution for a hoarding?” is the wrong question, and the answer people give (300 dpi) is wrong by an order of magnitude."}]},{"t":"p","runs":[{"text":"What matters is the "},{"text":"angular","b":true},{"text":" size of a detail at the viewing distance. The working figures used in the trade:"}]},{"t":"ul","items":[[{"text":"Viewed at "},{"text":"1 m","b":true},{"text":" (an exhibition panel, a poster): 150 ppi at final size."}],[{"text":"Viewed at "},{"text":"3 to 5 m","b":true},{"text":" (a shop board, a pull-up banner): 100 ppi."}],[{"text":"Viewed at "},{"text":"10 m","b":true},{"text":" (a building sign): 50 ppi."}],[{"text":"Viewed at "},{"text":"30 m or more","b":true},{"text":" (a hoarding, a motorway sign): "},{"text":"20 to 40 ppi","b":true},{"text":" at full size."}]]},{"t":"p","runs":[{"text":"A 6 × 3 m hoarding at 30 ppi is 7087 × 3543 pixels. That is an ordinary camera file. The image everybody panics about is usually already sufficient."}]},{"t":"p","runs":[{"text":"The other way to say it: build the artwork at "},{"text":"one-tenth scale at 300 ppi","b":true},{"text":", which is the same number of pixels and a document your machine can handle."}]},{"t":"p","runs":[{"text":"Vector artwork has no resolution at all","b":true},{"text":" and needs none of this. Only placed photographs do."}]},{"t":"h2","id":"legibility-and-the-rule-with-its-caveats","runs":[{"text":"Legibility, and the rule with its caveats"}]},{"t":"p","runs":[{"text":"The commonly quoted rule is "},{"text":"25 mm of capital height for every 3 m of viewing distance","b":true},{"text":": roughly one inch per ten feet. It comes from readability research and it is a floor for "},{"text":"legibility","i":true},{"text":", not a target for "},{"text":"impact","i":true},{"text":"."}]},{"t":"p","runs":[{"text":"The caveats matter:"}]},{"t":"ul","items":[[{"text":"It assumes good contrast, a clear typeface and a stationary reader."}],[{"text":"A "},{"text":"moving","b":true},{"text":" reader needs considerably more. Traffic signage standards use far larger letters for exactly this reason."}],[{"text":"A "},{"text":"condensed","b":true},{"text":" face at the same cap height is harder to read."}],[{"text":"Reversed","b":true},{"text":" type on a dark ground needs a slightly heavier weight at distance."}]]},{"t":"p","runs":[{"text":"So: 25 mm per 3 m as a minimum, doubled for anything read from a moving vehicle, and checked by printing a sample letter and walking away from it. That last test takes five minutes and settles every argument."}]},{"t":"h2","id":"panels-and-seams","runs":[{"text":"Panels and seams"}]},{"t":"p","runs":[{"text":"A hoarding is almost never one piece. Flex or vinyl comes on rolls of a limited width (commonly 1.6 m, 2.2 m or 3.2 m), so a 6 m banner is printed in panels and welded or overlapped."}]},{"t":"p","runs":[{"text":"Find out where the seams fall before you design.","b":true},{"text":" Then keep off them:"}]},{"t":"ul","items":[[{"text":"Faces, especially eyes and mouths."}],[{"text":"The logo."}],[{"text":"Any text."}],[{"text":"A precise geometric alignment that will visibly step at the join."}]]},{"t":"p","runs":[{"text":"Two or three questions to the fabricator (roll width, seam position, overlap or weld) and you can place your elements in the panels rather than across them."}]},{"t":"h2","id":"substrates-and-finishing","runs":[{"text":"Substrates and finishing"}]},{"t":"ul","items":[[{"text":"Flex / PVC banner","b":true},{"text":": the standard hoarding material. Needs "},{"text":"eyelets","b":true},{"text":" every 500 mm or so and a "},{"text":"hem","b":true},{"text":" (a folded, welded edge) for strength. Add "},{"text":"100 mm of extra material","b":true},{"text":" all round for the hem, and keep artwork out of it."}],[{"text":"Mesh","b":true},{"text":": perforated, for windy sites and building wraps. Passes wind, so the image is seen through holes and loses about 30% of its density; design for it."}],[{"text":"Self-adhesive vinyl on ACP","b":true},{"text":": shop boards."}],[{"text":"Foam board / Sunboard","b":true},{"text":": interior only, light, cheap."}],[{"text":"Backlit flex","b":true},{"text":": translucent, for lightboxes. Colours behave differently with light passing through them; ask for a sample lit from behind."}]]},{"t":"h2","id":"the-things-that-are-not-your-job-but-are-your-problem","runs":[{"text":"The things that are not your job but are your problem"}]},{"t":"ul","items":[[{"text":"Wind loading","b":true},{"text":" on a large sign is an engineering question and a legal one in many places. Not your decision, and worth asking about, because a sign that comes down is everybody’s problem."}],[{"text":"Planning permission and local rules","b":true},{"text":" on sign size, illumination and position exist in most jurisdictions and vary enormously. Ask the client whether they have it; do not advise on it."}],[{"text":"Installation access","b":true},{"text":": a sign 8 m up needs a ladder, a scaffold or a cherry picker, and the cost of that can exceed the sign."}]]},{"t":"h2","id":"what-to-send","runs":[{"text":"What to send"}]},{"t":"p","runs":[{"text":"1:1 if the RIP takes it, otherwise 1:10 with the scale in the filename. Vector for everything except photographs. CMYK, with a profile if the shop names one. Bleed of "},{"text":"25 to 50 mm","b":true},{"text":" rather than 3 mm, because large-format trimming is coarser. Hem and eyelet allowance marked on a separate layer. And a low-resolution reference JPEG so the operator can see what it should look like."}]}],"check":{"question":[{"text":"A 6 × 3 m hoarding is to be printed from a photograph that is 7000 × 3500 pixels. The designer refuses the image as too low resolution and asks the client for a larger file. Is this correct?"}],"options":[{"text":[{"text":"No: 7000 pixels across 6 m is about 30 ppi, which is normal for a hoarding read from 30 m."}],"correct":true,"tempting":null},{"text":[{"text":"Yes: any printed image below 300 ppi at final size will show visible pixellation regardless of distance."}],"correct":false,"tempting":[{"text":"The 300 ppi figure applies at reading distance. At 30 m the eye cannot resolve anything close to that level of detail."}]},{"text":[{"text":"Yes, but only because large-format RIPs upsample to 150 ppi internally and the source must exceed that figure."}],"correct":false,"tempting":[{"text":"RIPs do not impose a source resolution floor, and internal upsampling adds no detail that would justify rejecting the file."}]},{"text":[{"text":"No: the file should instead be resampled up to 150 ppi at full size before printing, which is what the RIP expects."}],"correct":false,"tempting":[{"text":"Reaches the right verdict on the refusal and then prescribes an upsample that adds interpolated pixels and no detail."}]}],"order":[1,2,3,0],"why":null},"prev":{"slug":"garment-printing-processes","title":"DTF, DTG, sublimation and heat transfer","minutes":8},"next":null}}