[{"data":1,"prerenderedAt":202},["ShallowReactive",2],{"marketing-blog-blog\u002Fscanning-in-bright-sun-and-low-light":3,"marketing-blog-related-blog\u002Fscanning-in-bright-sun-and-low-light":182},{"id":4,"title":5,"author":6,"body":7,"category":161,"date":162,"description":163,"draft":164,"extension":165,"image":166,"imageAlt":167,"imageCredit":168,"imageCreditUrl":169,"meta":170,"navigation":171,"path":172,"readTime":173,"seo":174,"stem":175,"tags":176,"__hash__":181},"blog\u002Fblog\u002Fscanning-in-bright-sun-and-low-light.md","Scanning in bright sun and low light","The CheckInHub team",{"type":8,"value":9,"toc":153},"minimark",[10,14,17,22,25,28,44,47,51,54,57,113,116,120,123,129,143,147,150],[11,12,13],"p",{},"You tested the scanning indoors, under even office light, and every pass read first time. Then doors opened at an outdoor festival in July, the afternoon sun came over the gate, and suddenly half the phone screens in the queue were unreadable mirrors. Or the opposite: an evening launch in a dark warehouse foyer, mood lighting only, and the camera could not find enough contrast to lock onto the code. Both failures feel like the software has broken. Neither has. It is light, and light is something you can plan for.",[11,15,16],{},"A QR scan is a camera reading a pattern of dark and light squares. Anything that destroys the contrast between those squares, or stops the camera focusing, breaks the read. Bright sun and deep gloom break it in opposite ways, and because most testing happens in pleasant indoor light, neither failure shows up until the day. The good news is that the causes are predictable and the fixes are cheap.",[18,19,21],"h2",{"id":20},"why-bright-sun-is-the-harder-problem","Why bright sun is the harder problem",[11,23,24],{},"Direct sunlight causes two separate problems at once. On a phone screen, the sun reflects off the glass, and the reflection sits on top of the code like a bright smear, hiding the squares underneath. On a printed pass, strong sun can wash the whole thing out and throw hard shadows across it from a hand or a lanyard. Either way, the camera is looking at a code that is no longer high-contrast, and it cannot read what it cannot see.",[11,26,27],{},"The instinct is to crank everyone's brightness up, and that helps a little with phone screens, but it does not solve the reflection. The reliable fix is to control the light at the scan point rather than fight it across the whole site. A few measures, in rough order of effectiveness:",[29,30,31,35,38,41],"ul",{},[32,33,34],"li",{},"Put the scan point in shade. A gazebo, an awning, or simply siting the lane on the shaded side of the gate removes most of the problem for free.",[32,36,37],{},"Angle the scanner away from the sun, so the guest tilts their phone into shadow rather than into glare.",[32,39,40],{},"Ask guests to lift screen brightness while they queue, on the email and on the signage, so they arrive ready.",[32,42,43],{},"For printed passes, use a matte stock rather than glossy, which throws far less reflection.",[11,45,46],{},"Shade is the big lever. If you take one thing from this piece, it is that a scanning lane in direct afternoon sun is a problem you can usually design away by moving it two metres into shadow.",[18,48,50],{"id":49},"why-low-light-is-gentler-but-still-bites","Why low light is gentler but still bites",[11,52,53],{},"Dim conditions are more forgiving than bright sun, because most phone screens are their own light source. A QR code on a phone glows in the dark, and a modern camera will read it from a lit screen in a near-black room. The trouble starts with printed passes, which have no light of their own, and with cameras that cannot focus when there is not enough light to see by.",[11,55,56],{},"Here the fixes flip. You are adding light rather than removing it.",[58,59,60,76],"table",{},[61,62,63],"thead",{},[64,65,66,70,73],"tr",{},[67,68,69],"th",{},"Condition",[67,71,72],{},"Symptom",[67,74,75],{},"Fix",[77,78,79,91,102],"tbody",{},[64,80,81,85,88],{},[82,83,84],"td",{},"Phone screen in dim foyer",[82,86,87],{},"Usually fine; occasional focus hunt",[82,89,90],{},"A small task light at the lane helps the camera focus",[64,92,93,96,99],{},[82,94,95],{},"Printed pass in dim foyer",[82,97,98],{},"Code too dark to read",[82,100,101],{},"Lamp angled at the scan surface, not at the guest's eyes",[64,103,104,107,110],{},[82,105,106],{},"Very dark, atmospheric venue",[82,108,109],{},"Camera cannot focus at all",[82,111,112],{},"Bright scan zone, even a single downlight, marks the lane",[11,114,115],{},"The principle is the same as the sunlight case in reverse: control the light at the one square metre where the scan happens, rather than re-lighting the venue. A single well-placed lamp at the lane fixes a problem that no amount of fiddling with phones will.",[18,117,119],{"id":118},"the-pass-design-does-half-the-work","The pass design does half the work",[11,121,122],{},"Lighting is the environment, but the pass itself decides how much margin you have. A code that fills more of the pass, sits on a clean white field, and carries plenty of quiet space around it survives poor conditions that would defeat a small, cramped, low-contrast code. A pass designed for the worst light you will face is a pass that reads everywhere.",[124,125,126],"blockquote",{},[11,127,128],{},"A code with generous size and a clean white border forgives bad light. A small code crammed into a busy design has no margin to give.",[11,130,131,132,137,138,142],{},"When you generate passes, favour a high error-correction level, which lets the code still read even when part of it is obscured by glare or a smudge, and never print the code reversed, light on dark, because many cameras struggle with inverted codes. We cover the wider set of pass-design choices in ",[133,134,136],"a",{"href":135},"\u002Fblog\u002Fdesigning-a-ticket-people-can-actually-scan","designing a ticket people can actually scan",", and the failure modes more broadly in ",[133,139,141],{"href":140},"\u002Fblog\u002Fwhat-goes-wrong-with-qr-check-in-and-how-to-avoid-it","what goes wrong with QR check-in, and how to avoid it",".",[18,144,146],{"id":145},"rehearse-in-the-actual-light","Rehearse in the actual light",[11,148,149],{},"The reason these problems surprise people is that nobody tests in the conditions that cause them. The fix is almost insultingly simple: go to the venue, at roughly the time of day doors will open, and scan a few real passes where the lane will actually be. If it is an outdoor afternoon event, test in the afternoon sun. If it is an evening event in a dark room, test in the dark. Five minutes of this finds problems that would otherwise find you live, in front of a queue.",[11,151,152],{},"CheckInHub will read a code in a wide range of conditions, on phones, tablets, and dedicated scanners, but no scanner can read contrast that is not there. The job that is yours, not the software's, is to make sure the light at the lane gives the camera something to work with. Get the shade or the lamp right, design the pass with margin to spare, and test in the real conditions, and the queue moves at the same eight-second pace whether the sun is blazing or the room is dim.",{"title":154,"searchDepth":155,"depth":155,"links":156},"",2,[157,158,159,160],{"id":20,"depth":155,"text":21},{"id":49,"depth":155,"text":50},{"id":118,"depth":155,"text":119},{"id":145,"depth":155,"text":146},"QR codes & scanning","2024-06-28","QR scanning that works perfectly in the office can fall apart in direct sun or a dim foyer. The fix is mostly physics, and mostly avoidable.",false,"md","https:\u002F\u002Fimages.unsplash.com\u002Fphoto-1662729429587-b3d05e230f8e?ixlib=rb-4.1.0&w=1600&q=80&auto=format&fit=crop","A crowd in front of a building with a large clock","Samuel Regan-Asante","https:\u002F\u002Funsplash.com\u002F@reganography?utm_source=checkinhub&utm_medium=referral",{},true,"\u002Fblog\u002Fscanning-in-bright-sun-and-low-light",5,{"title":5,"description":163},"blog\u002Fscanning-in-bright-sun-and-low-light",[177,178,179,180],"qr codes","scanning","passes","lighting","yZli2kFuUeaWZElgOYYgHS9ElJjL9oJvBWIBBa-wRdA",[183,190,196],{"to":184,"title":185,"description":186,"date":187,"category":161,"image":188,"readTime":189},"\u002Fblog\u002Fthe-eight-second-check-in-explained","The eight-second check-in, explained","What actually happens in the eight seconds a guest spends at the door, step by step, and why most of that time has nothing to do with scanning.","2026-06-19","https:\u002F\u002Fimages.unsplash.com\u002Fphoto-1662383729882-e03ce8e00887?ixlib=rb-4.1.0&w=1600&q=80&auto=format&fit=crop",6,{"to":191,"title":192,"description":193,"date":194,"category":161,"image":195,"readTime":189},"\u002Fblog\u002Fwhat-happens-in-the-moment-a-code-is-scanned","What happens in the moment a code is scanned","Between holding up a phone and the door turning green, a lot happens in well under a second. A plain-language look at the scan itself.","2026-02-20","https:\u002F\u002Fimages.unsplash.com\u002Fphoto-1706759755782-62bc9a0b32e1?ixlib=rb-4.1.0&w=1600&q=80&auto=format&fit=crop",{"to":197,"title":198,"description":199,"date":200,"category":161,"image":201,"readTime":173},"\u002Fblog\u002Freading-any-code-phones-tablets-and-wedge-scanners","Reading any code: phones, tablets and wedge scanners","The device that reads the code matters as much as the code itself. Phones, tablets and wedge scanners each suit a different door.","2025-10-24","https:\u002F\u002Fimages.unsplash.com\u002Fphoto-1595079834934-b78552e04b10?ixlib=rb-4.1.0&w=1600&q=80&auto=format&fit=crop",1782495583953]