Silver Efex Pro 2 - image halos

Discussion in 'Image Processing' started by robbie36, Jan 24, 2013.

  1. robbie36

    robbie36 Mu-43 All-Pro

    Sep 25, 2010
    Bangkok
    rob collins
    I really like Nik's Silver Efex in that it allows you to very quickly make great B+W conversions in lots of different ways. I notice a lot of other people use it on this site.

    One problem I find though is that it is terribly prone to 'image halos' - white lines around images within the frame. These sort of halos are generally associated with 'oversharpening' which would mean pushing the 'sturcture' sliders too far to the right in silver efex. I certainly try not to do this but I still get these 'image halos' - I wonder if anyone knows what I am doing wrong.

    As an example I post below a pic I posted in the PP7 challenge - you can see the halos on the 'overhead wires', the 'top of the building on the left' and the 'legs of the person on the right'.

    PP71-2_1_of_1_.
     
  2. elavon

    elavon Mu-43 All-Pro

    Sep 1, 2012
    Tel Aviv Israel
    Ehud
    I found this also halo in Color Effex. It is probably a problem in the NIK software algorithmic. When I process and see this effect in a filter I try to lower the sharpness level, and if it does not help I do not use the filter.
     
  3. Silver Efex has some very strong filters that enhance edge contrast to varying degrees, and many seem to go too far. It's not always just a matter of moving the sliders either because the different filters seem to have inherent prooperties that can't really be changed. I tried out most of them and have settled on using a mild filter based on one of the film types that I use about 95% of the time.
     
  4. savvy

    savvy Mu-43 Top Veteran

    714
    Sep 28, 2012
    SE Essex, UK
    Les
    Yes, I find this with SFXPro2 too. I always have to try and tone it down, whilst still attempting to preserve the main "effect" of the preset involved, not always successfully.

    I find myself playing with the "Dynamic Brightness", "Soft Focus", and "Fine Structure" sliders to try and tame it.
     
  5. savvy

    savvy Mu-43 Top Veteran

    714
    Sep 28, 2012
    SE Essex, UK
    Les
    BTW, here is one way of removing halos if you can't get rid of them any other way.

    It requires Photoshop, and uses the Clone Stamp tool in Darken Mode. I like that you don't have to be that accurate, as going over pixels that are not lighter has no effect.

    It can be a bit time consuming, though, if you've got lots of halos, but useful if they are isolated.

    Sharpening Halos And How To Hide Them - Tutorials
     
  6. robbie36

    robbie36 Mu-43 All-Pro

    Sep 25, 2010
    Bangkok
    rob collins
    Thanks... that is a really useful tip.