No announcement yet.

FFT making transparent images

  • Filter
  • Time
  • Show
Clear All
new posts

  • FFT making transparent images

    Hi everyone! Photo restoration is a hobby of mine, so I'm happy I found this place. I've been restoring some old photos of a family friend and thought to try the FFT filter on the harsh texture of the paper. Come to find out FFT only works on patterned texture, not frog skin texture. It's kind of charming anyway, so I suppose I'll leave it.

    Anyhoo, I decided to just play around with the filter with some images I found in tutorials. When I run the IFFT at the end of my dotting process I get images that are at about 50% opacity, maybe less. I'm scratching my head on this one. I make sure there is only one layer - the one I'm trying to edit. The image is in RGB mode, and everything seems to be going "as intended" until I run IFFT. I've tried on two different images and still got the same result.

    Does this sound like a PEBKAC error or is there a known issue of this sort with a fix?

    (PEBKAC meaning problem exists between keyboard and chair, hehe)

    Thanks for any insight someone might have!


  • #2
    Re: FFT making transparent images

    Hi Habs welcome to RetouchPro. Have you followed This Tutorial ?


    • #3
      Re: FFT making transparent images

      Hi Tony, thanks for getting back to me. Yes, that tutorial is actually how I found this site. I even tried the method on the textured half of the image, cropped so that the cleaned half wouldn't throw it off. Here's a screenshot of the result.


      • #4
        Re: FFT making transparent images

        I think the problem is likely to be that you are applying to a layer. The image needs to be flattened to be a "Background" image - it is this that you perform FFT.

        So if you duplicate your image first and apply flatten to the duplicate, then use your FFT filter. Copy the filtered version and paste it into the original as a new layer set to luminosity.


        Related Topics


        • Gerald McClaren
          Using the FFT filter to remove photo paper texture
          by Gerald McClaren
          Hi! Can someone please explain to me in the thread "Using the FFT filter to remove photographic paper texture", in the section "Put the colours back".
          Slide, with shift pressed (to align), your (now un-textured) luminosity back layer on top of the original(that's the one we...
          12-28-2014, 01:19 PM
        • AWAIS400
          fft filter..
          by AWAIS400
          Dear all hi.. I am awais from lahore pakistan.

          I am using cs3 on win xp and trying to repair my old photo. But i have a problem that when i scan this photo the photo paper texture is very visible .then i read about fft filter. But when i download and use it my system hang and not responding....
          05-04-2010, 01:33 AM
        • Liz
          Help: FFT Filter
          by Liz
          I've been using FFT for quite some time now. I sometimes have erratic results, but more so today. Despite re-installation of FFT, none of my problems were resolved. I'm using it on black and white wedding photos from the 70's, full of honeycomb. Lovely B&W's slightly discoloured through...
          07-01-2008, 03:17 AM
        • SPR
          Applying FFT Filter - Problems with IFFT
          by SPR
          Trying to remove print texture from an old photo (image 1). Applying FFT and brushing out white stars in red channel (image 2) Applying IFFT to RGB yields black border around objects in print. What am I doing wrong?

          Thank for help!...
          11-02-2016, 08:48 AM
        • Nicksfan
          Fast Fourier
          by Nicksfan
          I'm trying the FFT Tutorial and it's all good until I apply the IFFT. I get these crazy blotchy patterns. Can anyone help?
          02-06-2007, 05:46 PM