epaperpress PTLens

There are two version to this very useful, inexpensive and constantly updated program: a stand-alone version, and a plugin for photoshop. I have the stand-alone version, and it has allowed me to correct multiple distortions from different lenses given that it provides you with a HUGE data base of cameras and lenses from different companies. For example, the high barrel distorions of my Canon 17-85 IS USM ----specially at 17mm--- were easily corrected in a matter of seconds. But the program not only allows for corrections such as barrel distorion, it likewise allows for correction of Chromatic Aberrations in lenses such as the Canon 85 1.8 which ---though a true gem--- suffers from high chromatic abberation at 1.8.

Perhaps the only drawback of the stand-alone version is that you cannot correct raw files. The plugin does allow for this type of correction in RAW. However, thanks to Tom Niemann's generosity this program is extremely inexpensive (now $15) and for many years it was absolutely free! If you compare it to the cost of DxO, then there is really no competition. Niemann even compares his program to DxO on this site! He writes:

" Question. How does PTLens compare with DxO Optics Pro?

Answer. For distortion correction of distant objects (10 feet to infinity) results obtained from PTLens are similar to results from DxO. Both PTLens and DxO can process fisheye images, correct perspective distortion, and complex lens distortion such as moustache distortion. DxO has automatic corrections for vignetting and chromatic aberration (CA). PTLens has manual adjustments for vignetting and CA. DxO offers additional features including raw conversion, adjustments for distance, exposure compensation, noise reduction, and volume anamorphosis. DxO costs $79 (prosumer), $149 (SLR), and $299 (full frame SLR). PTLens costs $15."

Cost, generosity of creator, ease of use, constant updates for life.

Stand-alone version cannot process RAW files.

Excellent

wonderful tool for distortion, CA and vignetting correction for Photoshop. the plugin reads out the exif data of each photograph, i.e. lens, focal length, f-stop, and looks in the internal database for the paramters for correction. it uses internal panatools from Helmut Dersch. Highly recommended as dayly tool for each digital photographer!

very easy to handle, most of actual lenses and cameras are stored in the internal database. meanwhile also defishing for fiseye lenses and correction of chromatic aberrations (CA). easy to install. Freeware!

none

panatools itself, you will pay a lot of time for trying YOU correct parameters! Photoshop CS2 has the posbility of distortion correction. But with ptlens you have no trial and error, it works simply and straightforward.

very good, a lot of uoptdates, actual version 6.3.