1 Reply Latest reply on Aug 12, 2007 11:56 AM by Bill_Janes

    ACR sharpening required in 4.1???

    jrsforums
      In other thread, Jeff Schewe made the following statement:

      "...And what I discovered is that comparing 4.0 and 4.1 with NO SHARPENING is kinda useless because the sharpening was designed to be used with the new smoothing in the demosaicing, ya know? What I'm seeing is better edge detail and less super high frequncy noise from 4.1..."

      Is it really necessary to use ACR sharpening to get the best out of 4.1 Demosaicing? Why do go (great??) PS capture sharpening practices such as PKS, Focal Blade, or Glenn Mitchell's new scripts not do as good or better job?

      If ACR sharpening is required, are these the default? If not, and the ACR sharpening is needed, why are detailed sharpening discussions not provided?

      Based on Thomas Knoll's statement that 4.1 provided much smoother (less noisy) images (it was relative to jpeg size), I reran my Noise Ninja calibration profiles for my 5D. Not surprising, I found that on average, ACR sharpened (default 25/1.0/25/0) images were 3 to 5 points more noisy than unsharpened. If I need to use NN, that probably means I would need to turn ACR sharpening off, before using it....but does that mean I will not have the best image from ACR.

      I would appreciate a better understanding of what is best.

      Thanks...JOHN
        • 1. Re: ACR sharpening required in 4.1???
          Bill_Janes Level 2
          >Based on Thomas Knoll's statement that 4.1 provided much smoother (less noisy) images (it was relative to jpeg size), I reran my Noise Ninja calibration profiles for my 5D. Not surprising, I found that on average, ACR sharpened (default 25/1.0/25/0) images were 3 to 5 points more noisy than unsharpened. If I need to use NN, that probably means I would need to turn ACR sharpening off, before using it....but does that mean I will not have the best image from ACR.

          Sharpening should be done after noise reduction, or else you will be sharpening the noise. The 5D has very good noise characteristics, and NR would normally be needed only for high ISO or severely underexposed images. If you want to use ACR's sharpening on noisy images, you should try to do NR in ACR. Use of the new masking feature in ACR may help by limiting the sharpening to the edges in the image and thus protecting the surface areas (e.g. clear blue sky) from the sharpening.

          If noise is still too high, then you might want to use Noise Ninja or another specialized NR program. In this case you should turn off sharpening in ACR. ACR's NR is reportedly improved, but I doubt that it can do as good a job as Noise Ninja. Furthermore, in Photoshop you can do NR through a surface mask (the inverse of an edge mask) so as to protect the edges. Choose the best tools for the job.