8 Replies Latest reply on Apr 27, 2011 8:20 PM by Tai Lao

    Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta

    ajp9000

      The lens distortion correction on an AFS DX Nikkor 18-105mm seems to INCREASE Barreling instead of decreasing it. To get rid of the barreling I have to cut back on the Distortion correction. Anybody else experiencing this?

        • 1. Re: Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta
          areohbee Level 5

          ACR lens vignette correction for my 18-200 leaves a lot to be desired. Some people say theirs is "OK" - not sure why some people notice imperfections yet others do not. DxO and Nx2 correct the same photos perfectly, so I know in my cases, ACR is the problem... Not just 6.4 though. Dont have the 18-105.

          1 person found this helpful
          • 2. Re: Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta
            ajp9000 Level 1

            Thanks for the advice. I'll test other profiles with similar focal lengths. By the way, if you don't have the lens look around before getting it - it's the weak point of the D7000 kit. I just needed a VR lens and was hoping ACR would snap it up.

            • 3. Re: Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta
              Hudechrome Level 2

              I use that lens on a D90 and find it quite acceptable. It's not a weak point, as I have found by comparing output to dedicated lenses (comparing F/L to F/L, of course). However, I only use DXO for this job, as I cannot be confident in the corrections in ACR because of Adobe's policy concerning acquisition of the individual lens model data. I found the difficulty you mention when the ACR corrections first appeared. When I posted my objections to the process, feedback from people who were in the data supplier loop said the corrections were "good enough".

               

              My, oh my! What a way to run a correction system.

              • 4. Re: Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta
                ajp9000 Level 1

                When it comes to correcting inherent flaws in lenses today, it seems that we're all at the the mercy of of software engineers. I hope Adobe tweaks the profile in the final release of ACR 6.4, but I'll just pull the Distortion slider down to 30 or use a different profile for the mean time. Thanks for your input.

                Here's why I think that the 18-105 lens is the weak point of the D7000 kit. The camera is excellent and can be used for some professional work. The lens, on the other hand, has a plastic lens mount that screams "have backup ready" at me. In addition, I go fully manual at certain points when shooting an event [ie: reception money shots] and there is no distance scale to enable "zone focusing" and it is not a constant aperture lens - which isn't a prerequisite but I just prefer it to make sure that I'm not a stop or 2 under. In other, more casual, situations the lens, like you said, the lens can be very usable.

                • 5. Re: Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta
                  MadManChan2000 Adobe Employee

                  Do you have sample NEFs that demonstrate the problem?

                  • 6. Re: Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta
                    Hudechrome Level 2

                    What you say about overall usability is true (and unfortunate; all my film camera lenses, no matter how humble, had full control of all pertinent information), but I was referring to the corrections only.

                     

                    So far as software is concerned, it won't perfectly make a silk purse ... but it comes damn close! Years ago, I did lens testing, for oscilloscope cameras, and the rigor even for that was very demanding. What I know about the conditions necessary for obtaining repeatable results during such testing cannot change unless you are willing to accept less than optimum results. The penchant to "Let software correct it" has some painful connotations!

                     

                    Of course, the major source should be the lens makers themselves, but I fear this is a pretty guarded secret. No one wants to admit their failings, and because of the software correction capability, I suspect that certain parameters are of less concern at the lens tradeoff level. But Nikon or Canon isn't likely to tell you that!

                    • 7. Re: Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta
                      ajp9000 Level 1

                      Sent 20MB NEF and XMP file to this address but received an over limit

                      message - did you get them?

                       

                      Al

                      • 8. Re: Lens Distortion for 18-105 Nikkor increases in ACR 6.4 beta
                        Level 4

                        ajp9000 wrote:

                         

                        Sent 20MB NEF and XMP file to this address but received an over limit

                        message - did you get them?…

                         

                        Use the free yousendit.com service and post the download link here or email it to the recipient of your choice at that person's regular email address.

                         

                        You cannot attach or send files to the forum by email.

                         

                         

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                        Wo Tai Lao Le

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