Ouch! Now need help reducing grain in Photoshop

Hi All,

Bad day earlier this week. I did a drum scan of a medium format color neg and forgot to set the aperture correctly - result, a very grainy but high-rez scan (5000 dpi). So I re-scanned it and while doing so the tape holding the mylar and film to the rapidly-spinning drum came unstuck. Horrible sounds as half the negative got shredded.

Several lessons learned the hard way ...

But - my question. I'd still like to make a large print from the file I have. It's a pretty simple landscape - large grassy field, gray sky, couple of trees and buildings in the distance. What Photoshop techniques can I use to blend in the grain? It's small but strongly-colored grain - the scan is sharp as it stands.

My first idea is selection to mask for edges, invert the mask, and use some kind of blurring and/or de-saturation. Other ideas? Or is it hopeless?

Thanks, Ben

My guess is that the grain is most noticeable in the sky. If so, I would make a duplicate layer or new file and preserve the original. If you can isolate the sky try Gaussian blur. Another thing you can do would be to make another layer extending to just below the horizon and fill it with a similar gray or even a blue. Then make it a gradient going from top darker to white near the horizon. Adjust the density with the fill slider and transparency so you see what is in the background and how much is unwanted of the new sky layer. Erase what is unwanted. If that takes care of the problem, merge the layers and you are done. If there are other areas that need correction, make a duplicate layer and again apply the blur adjusting the amount as desired and erase the parts that need to be extra sharp as those will be maintained in the background layer. It may take some playing around until you get what you want so don't merge until you have it. Make a small print before enlarging. Darken the top (sky) corners slightly can also give a good effect. If you are so inclined check the PS plugin Photo Kit from Pixel Genius it has about 140 automated features that make an adjustment layer and really come in handy. Good luck.

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Ben

From my perspective there is not a way to fix this problem if you want to maintain sharpness through out Any fix Gaussian Blur, Surface Blur, noise reduction, de speckle all revolve around softening the image to some degree.
I am always looking for ways to clean old negs and trans that come into our shop due to bad storage, dust and bad process.
The bottom line for me at least that all fixes are done with some blur.
For your situation the noise is throughout the whole image which is even nastier.

If someone here has the cure then I would love to here it , as it would make my dustbusting life easier.

Somewhere in the data base I call my brain , I recall, sense a method of making a layer, moving the pixels one or two points sideways, do a blending mode in darken or lighten and paint out the offending noise , then moving back to the correct registration... this is only a figment of my imagination but something that may move dust busting in the right direction.

I am not sure that this would help the graininess you are seeing though.

sorry
Bob

Ben Altman said:

But - my question. I'd still like to make a large print from the file I have. It's a pretty simple landscape - large grassy field, gray sky, couple of trees and buildings in the distance. What Photoshop techniques can I use to blend in the grain? It's small but strongly-colored grain - the scan is sharp as it stands.

My first idea is selection to mask for edges, invert the mask, and use some kind of blurring and/or de-saturation. Other ideas? Or is it hopeless?

Click to expand...

By far the best software for film noise I've found is Imagenomic's Noiseware. Barring that, I would change to lab mode and then blur the a and b channels using guassian blur (try 2-4 pixels to begin with).

This will leave the luminosity noise which you can then reduce on the luminosity channel if you want..

I'm always a bit wary of reducing noise in some areas and not in others (it never looks quite natural). I would just try the Noiseware plugin first though..

The way I do this for my clients (If they see film grain as 'noise') is to use Photoshop plug-ins that analyze the structure of the noise and then give you control of the degree to which you remove it, such as Neatimage or Noise Ninja. As long as you have a small area such as sky that has no detail in it for the plug-in to scan and use the controls subtly then the result should look quite natural when you are finished. Obviously this will require you to spend some money, so you will have to decide how much is the smoothing of this image worth.

Thanks for the suggestions. I'll check them out.

Ben

Give Neat Image a try. It uses DSP processing to reduce grain and/or noise in images.
Neat Image - best noise reduction for digital cameras and scanners

Ben Altman said:

Hi All,

Bad day earlier this week. I did a drum scan of a medium format color neg and forgot to set the aperture correctly - result, a very grainy but high-rez scan (5000 dpi).
...
What Photoshop techniques can I use to blend in the grain? It's small but strongly-colored grain - the scan is sharp as it stands.

Click to expand...

If I were you, I'd be very warry of trying to get rid of that grain. You may actually discover you need the grain to get real good images during printing.

I only seriously found this out when I started paying more attention to the quality of digital (copy) prints made of flatbed scans of traditional wet darkroom A4 sized analog prints. I continuously found that if I made a digital copy print on an exact 1:1 reproduction scale, the digital print sucked compared to the analog one.

I just couldn't figure out what was wrong at first, why did the analog print look so my better?

Until I realized it had to do with the micro-contrast in the grain and fine details in the print, and that that in turn was highly influenced by the sharpness of the scan. Only by raising the sharpness considerably in Photoshop, and making a careful balance in the PPI scan resolution (I prefer 400 ppi - remember, this is print scanning, not negative scanning!), I managed to get results that were satisfactorily close to the original analog prints.

Also remember that most digital printer, in their dithering algorithms and ink dot patterns, already do a certain amount smoothing out. If I were you, I'd do a test and print both the original scan, and a blurred one, and see which turns out best.

Also see this on my homepage:
http://www.boeringa.demon.nl/menu_technic_optimalscanningresolution.htm

have you tried any of the skin scmoothing techniques, which maintainthe skin pores. that may work for this case too.