9 Replies Latest reply on Feb 21, 2016 10:54 PM by Marwan.Harmouche

    Manual lens correction not working properly.

    Marwan.Harmouche

      I am trying to correct the perspective of a image in lightroom and the vertical and horizontal manual lens corrections are not working properly, they are stretching the image in a weird way. I have used these sliders many times but I am not sure why sometimes they stretch the image. Here's a video that shows the effect of the sliders: Lightroom: Manual lens correction not working properly - YouTube. I would love to get your feedback on this is you know how I can solve this. Thank you,

        • 1. Re: Manual lens correction not working properly.
          trshaner Adobe Community Professional & MVP

          The LR Vertical and Horizontal Lens Correction controls are designed to "fix" perspective distortion. So what is "normal" perspective?

           

          Normal lens - Wikipedia, the free encyclopedia

           

          Wide angle lenses move the vanishing points further away and telephoto lenses pull them in closer.

           

          https://en.wikipedia.org/wiki/Perspective_distortion_%28photography%29

           

          LR's Vertical and Horizontal controls use the image file's focal length and camera metadata and adjust the image based on it's effective focal length. A 200mm lens if on a 1.5 crop factor body has an effective focal length of 300mm, which produces extreme telephoto perspective. That is why you see more "stretching" of the image when adjusting the Vertical control, than with lower focal length lenses (<100mmm).

           

          The YouTube video image file has very slight vertical converging verticals, slight clock-wise rotation, and slight pincushion distortion. You should be able to correct the image for parallel verticals with small Vertical and Rotation adjustment values. I suggest using 'Enable Profile Corrections' (Profile tab) to correct the small amount of lens distortion.

           

          If still having issues please post the image file to Dropbox or other file sharing site and I'll take a look at it. Thank you.      

          • 2. Re: Manual lens correction not working properly.
            Marwan.Harmouche Level 1

            @trshaner thanks a lot for your reply. I was using a full frame camera at 200mm, I tried to do a minor vertical perspective correction, it doesn't work because the picture is already highly stretched before I can get the line of the wall strait.

             

            You can download the picture from this link: Dropbox - Picture perspective correction

             

            Thank you,

            • 3. Re: Manual lens correction not working properly.
              trshaner Adobe Community Professional & MVP

              To be honest I've never used the LR Transforms tools with telephoto pictures. This 200 mm focal length raw image file has only 3 or 4 degrees of correction with the Vertical or Horizontal controls and merely "stretches" the image when pushing them further. Three things you can try:

               

              1) Use the Lens Corrections> Basic> Upright> Full control to "automatically" correct Level, Vertical, and Horizontal. It works quite well with this image, which is not always the case.

               

              Using Upright to Remove Lens Distortions in Lightroom 5 > Applying Upright Corrections

               

              2) Export the image file as a full-size 16bit ProPhoto RGB TIFF with the Export> Metadata panel set to 'Copyright Only. The TIFF will behave similar to shorter focal length images since it does not contain EXIF Focal Length data. Unfortunately you cannot fully correct Horizontal perspective with most images.

               

              3) Use Edit in Photoshop with Transform> Distort, which will allow full correction of the image.

               

              Transform Issue 200mm Focal Length.jpg

              • 4. Re: Manual lens correction not working properly.
                ssprengel Adobe Community Professional & MVP

                This is pretty close using just the lens correction area of Camera Raw filter, starting with Upright-Full, then tweaking the Transform parameters, which would be equivalent to LR's capability:

                I personally like it better with just the vertical perspective corrected, leaving a slant to the left for horizontal lines:

                • 5. Re: Manual lens correction not working properly.
                  DdeGannes Adobe Community Professional

                  I agree the third photo "Basic upright full" in trshaner's post, just does not look natural. Viewing from below there will be some natural distortion that is not anything to with the lens itself.

                   

                  Correcting for defects of the lens is one thing, changing the perspective of the natural angle of the view is going too far. Just my humble opinion.

                  • 6. Re: Manual lens correction not working properly.
                    trshaner Adobe Community Professional & MVP

                    DdeGannes wrote:

                     

                    I agree the third photo "Basic upright full" in trshaner's post, just does not look natural. Viewing from below there will be some natural distortion that is not anything to with the lens itself.

                     

                    Correcting for defects of the lens is one thing, changing the perspective of the natural angle of the view is going too far. Just my humble opinion.

                    It really depends on what "view" you are trying create. If the view is from the ground looking up it looks more natural to only apply Vertical correction. If you want the view as seen from a window in an adjacent building at the same height. then you need to use both Vertical and Horizontal correction.

                     

                    BTW- What's your take on the Vertical & Horizontal controls limited range (3 to 4 degrees) with a 200 mm focal length image? Doesn't seem right to me especially the stretching when set to more than about + or -20.

                    • 7. Re: Manual lens correction not working properly.
                      DdeGannes Adobe Community Professional

                      My opinion is that the correction applied should be what you would expect to physically see from the viewing location. The problem is deciding how much correction to apply to correct the distortion caused by the lens defects/ limitations, wide angle, telephoto etc. Or are you trying to correct to make it appear as if you are viewing at right angles both vertical and horizontal.

                      • 8. Re: Manual lens correction not working properly.
                        Marwan.Harmouche Level 1

                        Thank you Trshaner, I got to learn that perspective correction is linked to the file focal lens metadata. I didn't know that.

                        • 9. Re: Manual lens correction not working properly.
                          Marwan.Harmouche Level 1

                          Thank you all for your feedback.