Reduce "grain" (or noise), Canon inkjet...without softening details ?

Discussion in 'Digital Darkroom' started by terrykelly, Oct 15, 2020.

  1. Viewing an exhaustively NIK sharpened 13X19 Canon Pro-10 "B&W" inkjet print on Canon Pro Premium Matte PM-101paper from an APS-C file. .

    Subject is a group of corrugated steel farm barns , their hard edges up against white and a variety of grey skies.

    I played extensively with full range of NIK's possibilities including Focus, Contrast, Degree, viewing distance (selected 1.2-2.5 meters) and printer factors (I selected 1440X1440).

    I decided to limit adjustments to limit white outline sharpening artifact. The artifact I've settled on is soft...around 1/2 mm...can be readily seen in some areas with 5X PEAK LUPE (loupe).

    A color version has no sharpening artifact presumably because of all the color dots...this "B&W" print is actually NIK's lowest "coffee tone" .... looks like the old Agfa Portriga Rapid untoned.

    Thoughts? Perhaps a full frame (rather than APS) file would solve this, as might a Nikon scan from various 35mm films/chemicals.
     
  2. What's the problem I'm trying to address?

    Is there a way to further reduce sky grain/noise? That grain/noise is no problem at all in the subject areas...but might be if skin tone was an issue.
     
  3. I have tried Nik Collection Define2 noise reduction on noisy D70 file, but it was not as good as helicon noise filter or noise ninja around 2005 or thereabouts. I do not have helicon noise filter or noise ninja anymore, so cannot directly compare on same file. I ended up printing the image with canon ip100 without sharpening or noise reduction.

    I would not worry of artefacts that appear only with loupe, guests that see the print are likely to look it about three feet away.

    One possibility is to send slightly compressed jpeg file for wet process print, this should suppress noise a bit more than inkjet print from original.
     
  4. Can you give a link to the file or post it or some of it?
     
  5. it would be helpful if you posted the image, and even more helpful if you provided more detail about how you shot and edited. Was this a high-ISO shot? Was it exposed to the right? Did do your adjustments locally, or did you do them locally? In particular, was your sharpening global?

    This is a real puzzle. B&W doesn't use fewer dots, just fewer inks. How did you do the B&W conversion, and did you do any further editing after conversion?

    I don't think the paper or the printer have anything much to do with this. Even the cheaper Pro-100 has more than enough resolution to print 13 x 19 prints with no visible artifacts. I used a Pro-100 for several years and printed 13 x 19 on both coated and matte papers without a problem.
     
    digitaldog likes this.
  6. I think I should clarify more.

    All sensor produce noise. The first question is why you have a troubling amount. In general, noise is worse if you fail to expose to the right. The underlying issue is math: the ratio of signal strength to noise. if you expose to the right, you are maximizing signal, which helps to obscure the noise. Raising ISO exacerbates this problem because raising ISO is amplifying what comes off the sensor, both the signal you want and the noise you don't. However, even with fairly noisy sensors, you can usually get away with a substantial increase in ISO before things look really ugly if you remember to ETTR.

    All other things being equal--which they usually aren't--smaller sensors are more prone to noise because they generally have smaller photosites. However, if well exposed, an APS-C image should be fine. I've exhibited 13 x 19 prints taken with both APS-C and micro-four-thirds sensors, although my primary camera is FF.

    I don't know enough about what you are doing, but I suspect that the core issue in your processing isn't which tools you are using, but rather local vs. global adjustments.

    If you are sharpening globally, you're sharpening everything. In a sky, there often isn't much to sharpen other than noise. You should avoid sharpening areas like skies. There are several ways to do this, but I don't know how good NIK would be for this. It depends on how well you can use control points to exclude the sky from sharpening. I use NIK for some things, but never for sharpening. I sharpen either in Lightroom or Photoshop. Lightroom has a masking slider that you can adjust to block smooth areas from sharpening. It also allows you to sharpen with a local adjustment brush. Photoshop allows you to use masks and brushes to control what is and isn't sharpened, as well as how much different areas are sharpened.

    I don't know what you mean by selecting a "printer factor". The native resolution of Canon printers is 300 dpi. That's what I would choose for print resolution.
     
    mikemorrell likes this.


  7. Thanks for your thoughts.

    I use the Pro-10 rather than Pro-100 because Canon pigment (pro-10) makes better blacks/grays (more neutral) and is less prone to decay over time (reportedly). I think the Pro-100 may have advantages if the image is very graphic, poster-style. However I've seen a lot of beautiful conventional continuous tone prints from Pro-100. . .

    The Pro-10/Pro-100 do not cause the edge artifacts (white line) I experience...that's in the file due to ISO and/or excess post processing. Sometimes I get carried away with a photograph that would ideally call for a tripod and lower ISO.

    I prefer to sharpen "globally" because I'm too lazy to do it locally ...and/or because I prefer to avoid any local post processing...however, if I was making portraits of young women or making certain kinds of photo illustration (e.g. products) local post processing might be a good idea. If I worked with a pen rather than mouse, local adjustments might be more appealing.

    +++ I think use of fewer pigments ('B&W" vs color) results in fewer dots in an image. I will study to confirm this further.

    All of this aside, the "artifact" that bothers me the most is the white outline that results especially from over-processing...which I personally cause sometimes when photographing in difficult and/or rapidly changing light (due to reality that is common in the Southwest. I've sometimes been able to eliminate that particular artifact with very exhaustive border softening.
     
  8. The latest version of Topaz Denoise has an optional 'AI mode' which 'intelligently' reduces noise in an image based on a few parameters. 'Intelligent mode' means that noise/grain is more aggressively reduced in large, relatively homogenous areas of the photo while a lighter touch in applied for details, textures, edges, etc. It works really well on some photos but less well on others. I these cases I revert back to 'standard mode' (=the same level of noise reduction across the whole photo).

    If I really want to fine-tune my noise reduction, I make 2-3 (or even 4) duplicate layers in Photoshop and apply different levels of noise reduction to each of these (light to strong). I then create content-based layer masks for each of these. This allows me to blend in each (masked) noise reduction layer to get precise balance between 'reducing noise' and 'preserving sharpness of detail in textures, edges and other details'. The biggest advantage of this approach is that I can adjust the 'blending transparency' of each noise reduction layer, adjust the masks of each layer to include or exclude areas of the photo and even adjust the level of noise reduction in each layer. I've only ever felt the need to do this once or twice. But it's a (manual) way of applying a lower level of noise reduction to edges, textures and other details than to 'wide open spaces 'in the photo.

    Mike
     
  9. You missed the point. I wasn't recommending using a pro-100 rather than the pro-10. I was simply saying that the printer isn't your problem and that even the cheaper Pro-100 produces gorgeous prints.

    Given that you haven't posted an image, we're all guessing. But it sounds like you have two problems; noise in the sky and white halos. Not having seen the image, I think that the printer and the paper are irrelevant.

    Halos are usually caused by oversharpening.

    Re noise in the sky: if you have noise in the sky--often a result of underexposure or high ISOs--then sharpening the sky is going to make it worse. You wrote:

    That's the problem, not sensor size, paper, or printer. If you don't want to exacerbate noise in a smooth area, don't sharpen it. If you are too lazy (your word) to avoid sharpening smooth areas affected by noise, you will make the noise stand out more.
     
    digitaldog and mikemorrell like this.
  10. I forgot one thing. You didn’t answer the question about how you converted to. Lack and white. If you used NIK, some of the Silver Effexor conversions boost contrast considerably. You can see that both visually and in the histogram. That could add to the halos.
     
  11. Yes. SFEX can add contrast, just as it can reduce contrast. Use of a typical laptop or inadequate monitor can lead the photographer to miss that.

    SFEX< like the other NIK tools, is best controlled by its SLIDERS...which make all of its effects CONTINUOUS.
     
  12. true, but not relevant to the two problems you described.

    still haven’t see an image..
     
    digitaldog likes this.
  13. You can't see an image because I didn't post one. Most artifacts are easily controlled or prevented by sliders...including halos and noise ("grain")..
     
  14. Didn’t you start this thread by asking how to lessen two artifacts in photos that you won’t post?

    simply using the sliders isn’t he answer
     
    digitaldog likes this.

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