Lens distortion removal can help "flatten" images with a "fisheye" or barrel distortion, and make it easier for them to be used in creating maps. This is especially helpful when using photos from smaller cameras like the #mobius-action-cam and most #gopro cameras. Nathan Craig says: > Also, lens calibration is useful to consider when creating surfaces. In building large surfaces lens error can accumulate and result in distortion. Agisoft, the makers of PhotoScan, provide a free lens calibration program on their website. **** ## Questions [questions:lens-distortion] **** ## Activities There are a number of ways to remove lens distortion, including #fisheyegl, [**LensFun**](http://lensfun.sourceforge.net/), and **Agisoft Lens**. We're collecting guides on using these here; please add one if you can! [activities:lens-distortion] **** ## Lens databases Databases collecting lens geometries are available, for use with programs like this one: http://www.agisoft.ru/products/lens/ ### LensFun database The LensFun database is an open source database of lens models for correcting distortion. It'd be great to get the Canon A490 and SD 1300 series in there, and the format is: You can read more about how to calculate this and generate other types of camera model stuff here: http://lensfun.berlios.de/lens-calibration/lens-calibration.html...
| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| jhondue123456 | "https://www.google.com/ " | Read more » | 8 months ago | |||
| warren | "OK, we just did the GitUp 1 -- https://jywarren.github.io/fisheyegl/example/#a=0.989&b=0.98&Fx=0.05&Fy=0.14&scale=1.036&x=1.00..." | Read more » | over 5 years ago | |||
| stevie | "This is Awesome!!! Just getting to test it out now. Thanks so much for putting this together and posting the walk through :) " | Read more » | over 6 years ago | |||
| warren | "Folks on the #nasa #aren project sent in this image and we corrected it on the call: Lightdow LD6000 WiFi 1080P HD Sports Action Camera https://w..." | Read more » | about 7 years ago | |||
| warren | "Ah! And i realized another feature i forgot to mention -- you can now see the model of camera used to take the photos, which is extracted from the ..." | Read more » | about 7 years ago | |||
| warren | "Thanks, Pat. Also, I found a good example of lens distortion with straight lines (a parking lot) on MapKnitter just now: https://mapknitter.org/ma..." | Read more » | about 7 years ago | |||
| patcoyle | "Thanks Jeff, I did my test on iMac (24-inch, Early 2009) with Graphics shown as: NVIDIA GeForce GT 120 256 MB. " | Read more » | about 7 years ago | |||
| warren | "And a more final version of FisheyeGL is up here now! https://publiclab.org/n/14792 " | Read more » | about 7 years ago | |||
| warren | "Awesome! I'll just copy in your notes so they're searchable on the site: I saw Jeff Warren’s note, so gave it a try. I’ve used some of the other t..." | Read more » | about 7 years ago | |||
| patcoyle | "Nice Jeff. Here is a replication, but didn't think it warranted a note, see results in slides " | Read more » | about 7 years ago | |||
| warren | "Actually i'm pretty jazzed for the possibility of some of actually doing the lens correction for the Raspberry Pi cameras folks are using, onboard ..." | Read more » | over 7 years ago | |||
| cfastie | "Right click -- got it! I added the corrected version above. Yes, I think most point and shoot cameras correct for lots of lens artifacts before t..." | Read more » | over 7 years ago | |||
| warren | "OK, I've just updated with a change that stores the settings in the URL, so you can pass a URL to someone else with the current settings. For examp..." | Read more » | over 7 years ago | |||
| warren | "Hm, so the PowerShot S100 actually fudges pixels to correct lens distortion? But you turned that off for this test picture? Or was this precorrecte..." | Read more » | over 7 years ago | |||
| cfastie | "I tried with a photo from a PowerShot S100. That's the only camera I have other than the Mobius that has a fairly wide angle lens (24mm equiv.). Bu..." | Read more » | over 7 years ago | |||
| warren | "But be aware this is pretty beta software! It can crash! " | Read more » | over 7 years ago | |||
| warren | "The interface is really minimal at the moment, but i'm planning to make it save settings soon. But by "batch at the bottom" i mean that if you drag..." | Read more » | over 7 years ago | |||
| cfastie | "What do you mean it will batch them at the bottom? Is the information saved? Or do we have to write it all down? " | Read more » | over 7 years ago | |||
| warren | "@xose if you're testing any fisheye-lensed cameras please give it a try as well! " | Read more » | over 7 years ago | |||
| warren | "Hi, @patcoyle - managed (with some help) to get the web-based lens distortion removal system working, and worked out some rough settings for Mobius..." | Read more » | over 7 years ago | |||
| warren | "OK - the GoPro clones can be corrected with: a: 1, b: 1, Fx: 0.16, Fy: 0.16, scale: 1.087, x: 1, y: 1 Before: After: The Mobius (with defau..." | Read more » | over 7 years ago | |||
| warren | "This was solved today by SpaVec! https://github.com/jywarren/fisheyegl/issues/3#issuecomment-315491151 The demo is updated: https://jywarren.gi..." | Read more » | over 7 years ago | |||
| warren | "I've added more detail to the issue here; https://github.com/jywarren/fisheyegl/issues/3 Would be GREAT to get this figured out! " | Read more » | over 7 years ago | |||
| FrankA | "I found this very interesting: I use NVDI Modded Mobius.. Blue filter Lens for Mobius ActionCam - 6mm for $6.00 each from public labs I get very li..." | Read more » | over 7 years ago |