{"id":2951,"date":"2026-05-15T09:00:00","date_gmt":"2026-05-15T16:00:00","guid":{"rendered":"https:\/\/cinemagear.com\/blog\/?p=2951"},"modified":"2026-05-14T15:19:56","modified_gmt":"2026-05-14T22:19:56","slug":"balancing-arri-16-st-mirrored-shutters","status":"publish","type":"post","link":"https:\/\/cinemagear.com\/blog\/2026\/05\/15\/balancing-arri-16-st-mirrored-shutters\/","title":{"rendered":"Balancing ARRI 16-ST Mirrored Shutters"},"content":{"rendered":"\n

My friend Daniil Nevskiy is developing a Super 16 conversion for ARRI 16 S and ST cameras, and he asked if I could help him balance the mirrored shutters for the cameras he is working on. If you are unfamiliar, the mirrored shutter is a key part of the through-the-lens reflex viewfinding system for many cameras, including these ARRIs. Mirrored shutters in most reflexed cameras have a tolerance of .00003\u201d of flatness and parallelism to the shutter shaft. <\/p>\n\n\n\n

\"Balancing<\/figure>\n\n\n\n

If the mirrored shutter is not within these tolerances, the camera operator will see the image through the viewfinder bouncing around, which needless to say is very disturbing, and in some cases nauseating. This does not affect the image being photographed, it only affects the image in the viewfinder. <\/p>\n\n\n\n

\"Balancing<\/figure>\n\n\n\n

To begin this long and tedious process, I took an old fixture I had made to balance ARRI 2C shutters and modified it to work with the 16 S\/ST shutters. I had to design and 3D print a bearing block to support the shutter and shutter shaft, and I also had to design and 3D print a wrench to remove the screw that holds the shutter to the shutter shaft. The fixture is a stand that holds a precision dial indicator that measures in .00001\u201d increments, as well as the 3D printed bearing block that holds the mirrored shutter and shutter shaft. <\/p>\n\n\n\n

\"Balancing<\/figure>\n\n\n\n

The process I used is pretty straightforward: using the dial indicator, I measure the four corners of the mirrored sections of the shutter, making a sketch of where the errors are. Once the low spots have been determined, I remove the shutter from the shutter shaft, put a piece of gold leaf on the back of the mirror in those low spots, reinstall the shutter on the shutter shaft, and measure the four corners once again. The rest of the process is just chasing the errors until you get a reading that is within .00003\u201d total runout tolerance. In most cases, that means there is about a .00001\u201d error as the shutter turns, and that is nearly impossible to see. My plan is to work on these shutters one at a time in between other jobs, and then send them back to Daniil once they are all balanced.<\/p>\n","protected":false},"excerpt":{"rendered":"

My friend Daniil Nevskiy is developing a Super 16 conversion for ARRI 16 S and ST cameras, and he asked if I could help him balance the mirrored shutters for the cameras he is working on. If you are unfamiliar, the mirrored shutter is a key part of the through-the-lens reflex viewfinding system for many […]<\/p>\n","protected":false},"author":1,"featured_media":2947,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[4],"tags":[34,85,215,15],"class_list":["post-2951","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cameras","tag-16mm","tag-arri","tag-arri-s","tag-arriflex"],"_links":{"self":[{"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/posts\/2951","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/comments?post=2951"}],"version-history":[{"count":1,"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/posts\/2951\/revisions"}],"predecessor-version":[{"id":2952,"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/posts\/2951\/revisions\/2952"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/media\/2947"}],"wp:attachment":[{"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/media?parent=2951"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/categories?post=2951"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cinemagear.com\/blog\/wp-json\/wp\/v2\/tags?post=2951"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}