# What the hell flying thing did I record? **URL:** \ **Category:** Factual Questions\ **Created:** [August 22, 2021, 11:23pm UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332 "2021-08-22T23:23:22Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [August 22, 2021, 11:23pm UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332/1 "2021-08-22T23:23:22Z")
Early in the morning I was recording a video clip of a piece of acorn cap a spider was using as a [web anchor](https://www.iflscience.com/plants-and-animals/awesome-spider-dangles-rock-web/) (lifted around 4 feet off the ground) when a moth flew past the light. Except on the recorded video, it doesn’t look anything like–well, anything. Could this appearance of two sets of wings be the result of a CMOS rolling shutter artifact? Or more likely two of something mating? [![](https://img.youtube.com/vi/Q0lahZQL9N8/maxresdefault.jpg "Unidentified flying subject") ](https://www.youtube.com/watch?v=Q0lahZQL9N8) ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [August 23, 2021, 12:15am UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332/2 "2021-08-23T00:15:52Z")
No mystery. Shutter artifacts like this happen all the time. BTW–I have 25+ years in Aerial Photography. Yeah. Shutter artifact. The thing you shot was moving fat, & moving it’s wings even faster. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [August 23, 2021, 1:47am UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332/3 "2021-08-23T01:47:16Z")
Two cotton wood seeds flying in tandem? ---
**Author:** ![erysichthon](https://avatars.discourse-cdn.com/v4/letter/e/d07c76/32.png) [@erysichthon](https://boards.straightdope.com/u/erysichthon)\ **Post date:** [August 23, 2021, 2:08am UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332/4 "2021-08-23T02:08:08Z")
There’s an SD column about this phenomenon: > **[What’s up with “rods,” the mysterious insects that can be seen only on video?](https://www.straightdope.com/21342972/what-s-up-with-rods-the-mysterious-insects-that-can-be-seen-only-on-video)** > > A STAFF REPORT FROM THE STRAIGHT DOPE SCIENCE ADVISORY BOARD There’s also a Wikipedia article about it: > **[Rod (optical phenomenon)](https://en.wikipedia.org/wiki/Rod_(optical_phenomenon))** > > Pages for logged out editors learn more > > In cryptozoology and ufology, "rods" (also known as "skyfish", "air rods", or "solar entities") are elongated visual artifacts appearing in photographic images and video recordings. > Most optical analysis to date have concluded that the images are insects moving across the frame as the photo is being captured. > Robert Todd Carroll (2003), having consulted an entomologist (Doug Yanega), identified rods as images of flying insects recorded over sev... ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [August 23, 2021, 6:30am UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332/5 "2021-08-23T06:30:11Z")
Here is a 7-minute YouTube video that explains the “rolling shutter” artifact very thoroughly, with a whole lot of slow-motion simulations, featuring lots of airplane propellers and guitar strings and other fast-moving stuffs. Mindblowing! [![](https://img.youtube.com/vi/dNVtMmLlnoE/maxresdefault.jpg "Why Do Cameras Do This? | Rolling Shutter Explained - Smarter Every Day 172") ](https://www.youtube.com/watch?v=dNVtMmLlnoE) ---
**Author:** ![Kron](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kron/32/12444_2.png) [@Kron](https://boards.straightdope.com/u/Kron)\ **Post date:** [August 23, 2021, 6:39am UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332/6 "2021-08-23T06:39:25Z")
Thanks for that, fascinating! ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [August 23, 2021, 12:54pm UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332/7 "2021-08-23T12:54:41Z")
I appreciate your posting that. I knew about the effect, but his explanation simplifies it so I’ll be able to explain it to others. Thanks ---
**Author:** ![DesertDog](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/desertdog/32/11503_2.png) [@DesertDog](https://boards.straightdope.com/u/DesertDog)\ **Post date:** [August 23, 2021, 12:57pm UTC](https://boards.straightdope.com/t/what-the-hell-flying-thing-did-i-record/949332/8 "2021-08-23T12:57:24Z")
I’ve watched a number of flight deck videos and every time there’s a [Greyhound](https://en.wikipedia.org/wiki/Grumman_C-2_Greyhound) idling nearby – about the only aircraft with visible propellers – they look curvy. When being launched or coming for a landing they’re spinning too fast and just blur, like people expect. Generations ago the [focal plane shutter](https://en.wikipedia.org/wiki/Focal-plane_shutter) had a similar effect on still images, to the point where artists would draw a fast moving vehicle [leaning forward](https://en.wikipedia.org/wiki/Focal-plane_shutter#/media/File:Bundesarchiv_Bild_183-1991-1209-503,_Autorennen_im_Grunewald,_Berlin.jpg) to indicate it was speeding.