{"product_id":"cto-025","title":"CTO-025 Warming color-correction filter","description":"\u003cnav aria-label=\"Product family\"\u003e\u003cp\u003e\u003ca href=\"\/collections\/all-products\"\u003eAll optics\u003c\/a\u003e \/ \u003ca href=\"\/collections\/color-temperature-orange-warming-filter\"\u003eColor Temperature Orange Filters\u003c\/a\u003e\u003c\/p\u003e\u003c\/nav\u003e\u003cstyle\u003e\n.ko-reviewed{color:#222;font-family:inherit;line-height:1.65;overflow-wrap:anywhere}\n.ko-reviewed *{box-sizing:border-box}.ko-reviewed h2,.ko-reviewed h3{color:#005F96;line-height:1.3}\n.ko-reviewed h2{font-size:24px;margin:0 0 1rem}.ko-reviewed h3{font-size:19px;margin:1.7rem 0 .65rem}\n.ko-reviewed p{margin:.6rem 0 1rem}.ko-reviewed ul{padding-left:1.25rem;margin:.6rem 0 1rem}\n.ko-reviewed li{padding-left:.15rem;margin:.55rem 0}.ko-reviewed .ko-note{border-left:3px solid #c9dae4;padding:.65rem 1rem;background:#f7fafc;font-size:.95em}\n.ko-reviewed a{color:#005F96;text-decoration:underline}\n\n@media(max-width:480px){.ko-reviewed h2{font-size:22px}.ko-reviewed h3{font-size:18px}.ko-reviewed .ko-note{padding:.65rem .8rem}}\n\u003c\/style\u003e\u003csection class=\"ko-reviewed\"\u003e\u003ch2 class=\"ko-catalog-description-title\"\u003eWarming color-correction filter (CTO-025)\u003c\/h2\u003e\n\u003cp\u003eCTO-025 is listed as a warming color-correction filter. The supplied factory files contain different curves for this ID. Ask KUPO to confirm which version matches your sample or order before choosing the wavelength and transmission specifications.\u003c\/p\u003e\n\u003ch3\u003eOptical performance\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSource selection:\u003c\/strong\u003e Multiple factory versions are available. The comparison chart presents them separately; no numerical version is approved here.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCustomization:\u003c\/strong\u003e We can customize stock and sample-book designs. Tell us the wavelength response, size and operating conditions you need.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"ko-note\"\u003eThese values come from the measured samples and help you choose a starting design. We will agree the final specification for your order. Custom versions have their own specifications and measured curves.\u003c\/p\u003e\n\u003ch3\u003eApplications to consider\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication development:\u003c\/strong\u003e Use the available curves to discuss the required source, detector and wavelength response with KUPO. Confirm the product version before finalizing the application.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eChoosing this filter\u003c\/h3\u003e\n\u003cul\u003e\u003cli\u003eConfirm which factory version matches the sample you already have.\u003c\/li\u003e\u003c\/ul\u003e\n\u003ch3\u003eCustom options\u003c\/h3\u003e\n\u003cp\u003eStart with this stock or sample-book design, then tell us what you need to change. We can discuss the wavelength bands, transmission, blocking, angle, glass material, size and operating conditions with you, and agree a specification for your custom filter.\u003c\/p\u003e\u003c\/section\u003e\u003ch3\u003eTransmission spectra: unconfirmed versions\u003c\/h3\u003e\u003ciframe src=\"https:\/\/charts.kupooptics.com\/CTO-025.html\" title=\"CTO-025 transmission spectrum with wavelength readout\" loading=\"lazy\" width=\"100%\" height=\"880\" style=\"border:0;width:100%;height:clamp(850px,calc(43vw + 350px),940px);\" referrerpolicy=\"no-referrer-when-downgrade\"\u003e\u003c\/iframe\u003e\u003csection class=\"ko-reviewed ko-product-faq\" aria-label=\"Product questions\"\u003e\u003ch2\u003eQuestions about CTO-025\u003c\/h2\u003e\n\u003ch3\u003eWhich CTO-025 curve should I use?\u003c\/h3\u003e\n\u003cp\u003eThe factory files contain two different versions under this reference. Neither has been selected as the order specification. Send us your sample-book edition, an existing sample or the specification you need so we can identify the matching version.\u003c\/p\u003e\n\u003ch3\u003eCan I still use CTO-025 as a starting point for a warming filter?\u003c\/h3\u003e\n\u003cp\u003eYes, as a discussion reference. The two curves are shown separately above so you can explain which response you need. Confirm the version before comparing transmission values or choosing dimensions for an order.\u003c\/p\u003e\u003c\/section\u003e\u003cp\u003e\u003ca href=\"\/pages\/contact\"\u003e\u003cstrong\u003eDiscuss this filter with KUPO\u003c\/strong\u003e\u003c\/a\u003e - include the product reference, source wavelength, working angle and required dimensions.\u003c\/p\u003e\u003cstyle\u003e#MainContent .ko-reviewed\u003eh2.ko-catalog-description-title{font-size:27px;font-weight:500;line-height:1.4;letter-spacing:-.01em;color:#0c324b;background:#f0f6f9;padding:20px 24px;}#MainContent .ko-reviewed\u003eh2.ko-catalog-description-title+p{border-bottom:0;}@media(max-width:650px){#MainContent .ko-reviewed\u003eh2.ko-catalog-description-title{font-size:24px;}}\u003c\/style\u003e","brand":"KUPO Optics","offers":[{"title":"Color Temperature Orange (Warming) Filter \/ 3\/4 CTO","offer_id":48516667244799,"sku":"CTO-025","price":0.0,"currency_code":"TWD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0818\/8651\/1359\/files\/cto-025-spectrum.jpg?v=1778712861","url":"https:\/\/kupooptics.com\/products\/cto-025","provider":"KUPO Optics","version":"1.0","type":"link"}