Page 1 of 2 12 LastLast
Results 1 to 10 of 20

Thread: sharpening high resolution film scans

  1. #1

    Join Date
    Sep 2011
    Location
    San Francisco
    Posts
    92

    sharpening high resolution film scans

    Now that I have the luxury of working with very good scans of my film images, I'm encountering a new problem. Most of the newer sharpening routines such as the detail group in LR are not working well with these high resolution scans - they just pronounce the grain or do weird things to the grain, but not sharpen the parts of the image I want. I feel like I need to go back to old PS techniques like find edges, or frequency separation to do the image justice. I wish I could take advantage of the newer software such as inside LR or C1 that recover some loses due to diffraction or shake but unfortunately the results are all that pleasing. I'm curious to know what others here are doing with their high resolution scans?

  2. #2

    Join Date
    Jul 2016
    Posts
    4,566

    Re: sharpening high resolution film scans

    Hello,

    A very good sharpening job (IMHO) may require sometimes the local application of the sharpening filters. In a portrait we may want a different sharpening strategy for eyes that for a cheek. Not wanting to be intrussive aganist the image with PS, but local application may have a lot of sense. This requires working with masks and layers.

    Sometimes we adjust sharpening with a few clicks, and LR is enough for it, sometimes we may want a certain refined job and Ps is the right tool.

    There is another important thing: resizing algorithm, in the Ps image size dialog (at bottom) you select the algorithm, "bicubic ideal for reductions" is not the default one, but the interesting one, for pixel level acutance.

    Regards

  3. #3
    Steven Ruttenberg's Avatar
    Join Date
    Sep 2017
    Location
    Mesa, AZ
    Posts
    2,779

    Re: sharpening high resolution film scans

    I use mid-tone sharpening unsharp mask. I can paint out the areas I don't want sharpened oe want a different sharpening or sharpening technique. I love layer masks and paint on them.

  4. #4
    Peter De Smidt's Avatar
    Join Date
    Jan 2001
    Location
    Fond du Lac, WI, USA
    Posts
    8,954

    Re: sharpening high resolution film scans

    One way is to use high radius low amount unsharp masking. This increases mid-tone contrast, including macro details, without going nut's on really fine detail. I do also use high pass sharpening quite a bit. There are fancier ways, but I've found that the better my original, the less I need sharpening, and over-sharpening is way worse than undersharpening.
    “You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
    ― Alexander Den Heijer, Nothing You Don't Already Know

  5. #5

    Join Date
    May 2016
    Location
    Licking County, Ohio
    Posts
    340

    Re: sharpening high resolution film scans

    I have not tried it in your specific use case, but you might want to try a the high-pass sharpening technique. Duplicate the layer (or make stamp visible layer if you have a stack of layers). De-saturate the new layer. Set the blending mode to Soft Light. Convert the layer to a Smart Object (this allows you to change your radius on High Pass to see what works best). Apply the High Pass filter (Filters>Other>High Pass). You probably want to pick a larger radius on a high-resolution scan to ensure that it gets to the point of sharpening image detail (which covers many pixels). Create a layer mask and set it to all black (so the high pass sharpening is not applied anywhere in the image). Then use the paint brush to paint white into the layer mask where you want sharpening applied (say, paint the mask white over the eyes but leave the mask black over the out-of-focus background areas). Once happy, Rasterize the layer to save space and processing overhead before saving the file.

  6. #6
    David Lobato David Lobato's Avatar
    Join Date
    Feb 2011
    Location
    Baltimore MD
    Posts
    1,054

    Re: sharpening high resolution film scans

    Try doing noise reduction before sharpening. In photoshop use the Camera Raw Filter up on the menu. Zoom to 100% and observe the effects of grain while slowly adding luminance noise reduction. Then still at 100% do the sharpening on the magnified image. Observe the effects on the image while sharpening is added. Adjust both the Amount and the Radius in sharpening.You may need to go back to re-adjust the noise reduction. You will learn a balancing act to get the best of noise reduction and sharpening working together.

  7. #7
    Steven Ruttenberg's Avatar
    Join Date
    Sep 2017
    Location
    Mesa, AZ
    Posts
    2,779

    Re: sharpening high resolution film scans

    Quote Originally Posted by williaty View Post
    I have not tried it in your specific use case, but you might want to try a the high-pass sharpening technique. Duplicate the layer (or make stamp visible layer if you have a stack of layers). De-saturate the new layer. Set the blending mode to Soft Light. Convert the layer to a Smart Object (this allows you to change your radius on High Pass to see what works best). Apply the High Pass filter (Filters>Other>High Pass). You probably want to pick a larger radius on a high-resolution scan to ensure that it gets to the point of sharpening image detail (which covers many pixels). Create a layer mask and set it to all black (so the high pass sharpening is not applied anywhere in the image). Then use the paint brush to paint white into the layer mask where you want sharpening applied (say, paint the mask white over the eyes but leave the mask black over the out-of-focus background areas). Once happy, Rasterize the layer to save space and processing overhead before saving the file.
    This is a bit more detailed than I do for high pass. I generally make a duplicate layer, then choose soft light or overlay, etc. Choose high pass apply the radius and observe the effect. I have also found it takes a lot more radius to effect a sharpening than for a true digital file. I am gonna try this method of sharpening.

  8. #8
    Steven Ruttenberg's Avatar
    Join Date
    Sep 2017
    Location
    Mesa, AZ
    Posts
    2,779

    Re: sharpening high resolution film scans

    Quote Originally Posted by Peter De Smidt View Post
    One way is to use high radius low amount unsharp masking. This increases mid-tone contrast, including macro details, without going nut's on really fine detail. I do also use high pass sharpening quite a bit. There are fancier ways, but I've found that the better my original, the less I need sharpening, and over-sharpening is way worse than undersharpening.
    Agree too much sharpening makes the image look, well, like a horror show.

  9. #9
    Steven Ruttenberg's Avatar
    Join Date
    Sep 2017
    Location
    Mesa, AZ
    Posts
    2,779

    Re: sharpening high resolution film scans

    Quote Originally Posted by David Lobato View Post
    Try doing noise reduction before sharpening. In photoshop use the Camera Raw Filter up on the menu. Zoom to 100% and observe the effects of grain while slowly adding luminance noise reduction. Then still at 100% do the sharpening on the magnified image. Observe the effects on the image while sharpening is added. Adjust both the Amount and the Radius in sharpening.You may need to go back to re-adjust the noise reduction. You will learn a balancing act to get the best of noise reduction and sharpening working together.
    Interesting. I generally try to avoid noise reduction if possible.

  10. #10

    Join Date
    Sep 2011
    Location
    San Francisco
    Posts
    92

    Re: sharpening high resolution film scans

    Hi All,
    Thanks for all the tips. I have also heard from others via e-mail that they don't sharpen their film scans at all. I'm not using the sharpening in the scanner software so feel I do need to sharpen somewhat, particularly for larger prints.

    Here's a summary of what I've tried so far:
    LR - with and without noise reduction - the settings have to be so low - about 35 sharpening, and threshold about 25 or higher to avoid sharpening the grain too much. I still think this filter works better with lower res images.
    PS - smart sharpen, and unsharp mask
    Topaz InFocus - this was very gentle and using low settings some detail is coaxed out but not really enough - higher settings and the image became overly crunchy.

    The best results from a simple plugin/filter so far seem to come from the new photoshop cc filter - Shake Reduction
    But I think my best results have come from using the graphic equalizer/frequency separation technique where I apply the high pass on duplicate layers using scaled radius settings - these layers then set to linear light blend mode. I just vary the opacity of each layer and this could be painted in selectively too.

    I haven't tried the old school method of finding edges yet or the new diffraction recovery tool in C1 yet, but plan to do so.
    My guess is there might be some scientific tools in ImageJ that work on fourier tranforms that can side step the noise, but I only know a tiny bit about that stuff, however I've seen some magic done with it.

    I'm not really wanting to reduce the grain so much as pull the image out of the grain if that makes sense.

Similar Threads

  1. Adox CMS II 20 ISO High Resolution Film
    By Tim V in forum Darkroom: Film, Processing & Printing
    Replies: 7
    Last Post: 1-Dec-2017, 08:26
  2. How Lower Resolution Lens Works on Large High Resolution Wet Plate Negative
    By Mustafa Umut Sarac in forum Lenses & Lens Accessories
    Replies: 2
    Last Post: 16-Jan-2014, 15:04
  3. Sharpening Post Drum Scans?
    By greyspecks in forum Digital Processing
    Replies: 3
    Last Post: 10-Mar-2008, 07:55
  4. Sharpening Negative Scans-What is the Best Approach
    By JPlomley in forum Digital Processing
    Replies: 18
    Last Post: 29-Dec-2007, 13:27
  5. sharpening drum scans
    By adrian tyler in forum Digital Hardware
    Replies: 23
    Last Post: 25-Nov-2005, 11:50

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •