![ptlens database ptlens database](http://www.pindelski.org/Blog/Hearst_Defish.jpg)
For example, I found my main camera, the Casio EX-P600 in there, but not my newer Fujifilm F31. The only other limitation is that the camera database does not seem to have been updated in a while. I’ll post another example later that shows the vignetting correction. Click on the pictures to view them in Flickr and then select “All Sizes” to see the effect of the barrel distortion and correction better at larger sizes. It’s a little tricky to get the database set up and to figure out the correct string to use, but from then on out it’s dead simple to use. The extra cool feature of this tool is that it can read the camera make and model from the EXIF data and look up the necessary coefficients in a database (just some flat text files) stored in your home directory. It sounds like it can correct for some types of chromatic aberration as well. I mostly use it to correct for the barrel distortion and vignetting that occurs using my zoom lens at the widest setting. “Apply radial or flatfield vignetting correction as well as geometrical radial distortion and transversal chromatic abberration correction.” (sic)
#Ptlens database install
I installed it on Ubuntu easily by: $ sudo apt-get install hugin-tools It uses the panorama tools library (yes, the same excellent one by Helmut Dersch, now a full open source project) to do lens corrections based on (my research is weak here) mathematical models for optimal lens behavior.
![ptlens database ptlens database](https://www.epaperpress.com/ptlens/images/shift3.gif)
I’d like to draw your attention to a little command-line tool that I’ve run across that is very good at doing one thing: lens correction.