{"id":7181,"date":"2022-02-07T16:06:30","date_gmt":"2022-02-07T16:06:30","guid":{"rendered":"https:\/\/www.pmstudios.co.uk\/blog\/?p=7181"},"modified":"2022-02-07T16:06:30","modified_gmt":"2022-02-07T16:06:30","slug":"starting-with-infra-red-photography-part-7-testing-modern-lenses","status":"publish","type":"post","link":"https:\/\/www.pmstudios.co.uk\/blog\/?p=7181","title":{"rendered":"Starting with Infra-Red Photography Part 7 &#8211; Testing modern lenses"},"content":{"rendered":"\n<p>I am aware that modern lenses are not necessarily suitable for infra-red photography as they often produce hotspots &#8211; I have read that this is due to the type of glass used in modern lenses. So, before I get my camera converted, I thought I would undertake some testing of my lenses.<\/p>\n\n\n\n<p>First up is my 10-24mm wide-angle zoom. The presence and intensity of the hotspot varies with the wavelength passed by the filter:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0079-600x400.jpg\" alt=\"\" class=\"wp-image-7182\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0079-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0079-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0079-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0079-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0079.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>10mm focal length, 720nm filter, no discernible hotspot<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0088-600x400.jpg\" alt=\"\" class=\"wp-image-7183\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0088-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0088-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0088-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0088-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0088.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>10mm focal length, 760nm filter, visible hotspot<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0094-600x400.jpg\" alt=\"\" class=\"wp-image-7184\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0094-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0094-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0094-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0094-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0094.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>10mm focal length, 850nm filter, definite hotspot<\/figcaption><\/figure>\n\n\n\n<p>Other tests of this lens with different apertures showed the same problem. A similar result is for the 18-55mm lens:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0106-600x400.jpg\" alt=\"\" class=\"wp-image-7185\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0106-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0106-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0106-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0106-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0106.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>18mm focal length, 720nm filter no discernible hotspot<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0112-600x400.jpg\" alt=\"\" class=\"wp-image-7186\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0112-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0112-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0112-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0112-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0112.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>18mm focal length, 760nm filter, visible hotspot<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0118-600x400.jpg\" alt=\"\" class=\"wp-image-7187\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0118-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0118-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0118-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0118-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0118.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>18mm focal length, 850nm filter, strong hotspot<\/figcaption><\/figure>\n\n\n\n<p>The best lens proved to be the 55-200 telephoto zoom:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0154-600x400.jpg\" alt=\"\" class=\"wp-image-7188\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0154-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0154-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0154-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0154-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0154.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>200mm focal length, 720nm filter, no discernable hotspot<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0169-600x400.jpg\" alt=\"\" class=\"wp-image-7189\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0169-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0169-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0169-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0169-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0169.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>200mm focal length, 850nm filter, no discernable hotspot<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"400\" src=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0175-600x400.jpg\" alt=\"\" class=\"wp-image-7190\" srcset=\"https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0175-600x400.jpg 600w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0175-300x200.jpg 300w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0175-150x100.jpg 150w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0175-768x512.jpg 768w, https:\/\/www.pmstudios.co.uk\/blog\/wp-content\/uploads\/2022\/02\/F22_0175.jpg 1000w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption>200mm focal length, 950nm filter, there might just be signs of a hotspot<\/figcaption><\/figure>\n\n\n\n<p>At least I have some idea what to expect from my modern lenses&#8230;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I am aware that modern lenses are not necessarily suitable for infra-red photography as they often produce hotspots &#8211; I have read that this is due to the type of glass used in modern lenses. So, before I get my camera converted, I thought I would undertake some testing of my lenses. First up is &hellip; <a href=\"https:\/\/www.pmstudios.co.uk\/blog\/?p=7181\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Starting with Infra-Red Photography Part 7 &#8211; Testing modern lenses&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[126,65],"tags":[],"class_list":["post-7181","post","type-post","status-publish","format-standard","hentry","category-infra-red","category-technical"],"_links":{"self":[{"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/posts\/7181","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7181"}],"version-history":[{"count":2,"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/posts\/7181\/revisions"}],"predecessor-version":[{"id":7192,"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=\/wp\/v2\/posts\/7181\/revisions\/7192"}],"wp:attachment":[{"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7181"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7181"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.pmstudios.co.uk\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7181"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}