{"id":21304,"date":"2025-10-07T11:39:03","date_gmt":"2025-10-07T10:39:03","guid":{"rendered":"https:\/\/johnjohnston.info\/blog\/?p=21304"},"modified":"2025-10-07T13:04:52","modified_gmt":"2025-10-07T12:04:52","slug":"black-and-white-magick","status":"publish","type":"post","link":"https:\/\/johnjohnston.info\/blog\/black-and-white-magick\/","title":{"rendered":"Black and White Magick"},"content":{"rendered":"\n<figure data-wp-context=\"{&quot;imageId&quot;:&quot;69db259905280&quot;}\" data-wp-interactive=\"core\/image\" data-wp-key=\"69db259905280\" class=\"wp-block-image size-large wp-lightbox-container\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" data-attachment-id=\"21305\" data-permalink=\"https:\/\/johnjohnston.info\/blog\/black-and-white-magick\/img_2545-threshold-25\/\" data-orig-file=\"https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25.png\" data-orig-size=\"2400,1800\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"IMG_2545-threshold-25\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25-1024x768.png\" data-wp-class--hide=\"state.isContentHidden\" data-wp-class--show=\"state.isContentVisible\" data-wp-init=\"callbacks.setButtonStyles\" data-wp-on--click=\"actions.showLightbox\" data-wp-on--load=\"callbacks.setButtonStyles\" data-wp-on-window--resize=\"callbacks.setButtonStyles\" src=\"https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25-1024x768.png\" alt=\"High-contrast black and white image of a forest with tall trees and dappled sunlight.\" class=\"wp-image-21305\" srcset=\"https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25-1024x768.png 1024w, https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25-620x465.png 620w, https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25-768x576.png 768w, https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25-1536x1152.png 1536w, https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25-2048x1536.png 2048w, https:\/\/johnjohnston.info\/blog\/wp-content\/uploads\/2025\/10\/IMG_2545-threshold-25-668x501.png 668w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><button\n\t\t\tclass=\"lightbox-trigger\"\n\t\t\ttype=\"button\"\n\t\t\taria-haspopup=\"dialog\"\n\t\t\taria-label=\"Enlarge\"\n\t\t\tdata-wp-init=\"callbacks.initTriggerButton\"\n\t\t\tdata-wp-on--click=\"actions.showLightbox\"\n\t\t\tdata-wp-style--right=\"state.imageButtonRight\"\n\t\t\tdata-wp-style--top=\"state.imageButtonTop\"\n\t\t>\n\t\t\t<svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"12\" height=\"12\" fill=\"none\" viewBox=\"0 0 12 12\">\n\t\t\t\t<path fill=\"#fff\" d=\"M2 0a2 2 0 0 0-2 2v2h1.5V2a.5.5 0 0 1 .5-.5h2V0H2Zm2 10.5H2a.5.5 0 0 1-.5-.5V8H0v2a2 2 0 0 0 2 2h2v-1.5ZM8 12v-1.5h2a.5.5 0 0 0 .5-.5V8H12v2a2 2 0 0 1-2 2H8Zm2-12a2 2 0 0 1 2 2v2h-1.5V2a.5.5 0 0 0-.5-.5H8V0h2Z\" \/>\n\t\t\t<\/svg>\n\t\t<\/button><\/figure>\n\n\n\n<p>I&#8217;ve been messing about with the simplest ImageMagick scripts again. <\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>magick  \"$file\"  -threshold 25% -fill white +opaque black  \"${file%.*}bw25.gif\"\n<\/code><\/pre>\n\n\n\n<p>Sort of thing. Changing the threshold repeatedly. A few more on <a href=\"https:\/\/www.flickr.com\/photos\/troutcolor\/albums\/72177720329513757\/\">Flickr<\/a>. I am not sure why I like these but I do.<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>I&#8217;ve been messing about with the simplest ImageMagick scripts again. Sort of thing. Changing the threshold repeatedly. A few more on Flickr. I am not sure why I like these but I do.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"status","meta":{"mf2_syndication":["https:\/\/social.ds106.us\/@johnjohnston\/115332454071021589","https:\/\/bsky.app\/profile\/johnjohnston.info\/post\/3m2lwsase5x2d"],"advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"webmentions_disabled_pings":false,"webmentions_disabled":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[953],"tags":[662,332],"post_format":[642],"class_list":{"0":"post-21304","1":"post","2":"type-post","3":"status-publish","4":"format-status","6":"category-posse","7":"tag-imagemagick","8":"tag-photo","9":"post_format-post-format-status","10":"kind-article","12":"h-entry","13":"hentry"},"better_featured_image":null,"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p57zFQ-5xC","jetpack_likes_enabled":false,"jetpack_sharing_enabled":true,"kind":false,"_links":{"self":[{"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/posts\/21304","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/comments?post=21304"}],"version-history":[{"count":2,"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/posts\/21304\/revisions"}],"predecessor-version":[{"id":21307,"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/posts\/21304\/revisions\/21307"}],"wp:attachment":[{"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/media?parent=21304"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/categories?post=21304"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/tags?post=21304"},{"taxonomy":"post_format","embeddable":true,"href":"https:\/\/johnjohnston.info\/blog\/wp-json\/wp\/v2\/post_format?post=21304"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}