Blending artifact Pixelation issue

  • Hello, I'm currently working on a drawing using the air brush and a custom brush and i notice that there is a significant amount of pixelation in the blending. I want to know if I'm doing something wrong here. I'm working on 300 DPI on a raster layer. Here's a preview of the drawing

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    Anything would help, thanks.

  • 300 DPI doesn't mean anything on it's own. 10inches X 6inches at 300 DPI is not the same as 5inches X 3inches at 300DPI.

    How are the anti-aliasing settings on the custom brush? The air-brush is usually set to middle anti-aliasing.

    Is this image exported? Are you seeing the blended steps on the working file in CSP or just on the exported image?

  • The page I'm working on is A4 the brush I'm using has anti aliasing set to middle. and its not an exporting problem this happens while I'm blending colors.

  • I'm seeing it too. I don't use airbrush much so as a test I tried a circle gradient. The steps are there as well. This is 70cm X 50cm at 300ppi.


    You just can't squeeze more resolution out of a canvas than it can give.

  • If the air brush has stepping that is more noticeable than the gradient (the gradient would represent the least visible stepping at that resolution) you could try to make a selection of the really noticeable areas and apply a Gaussian Blur filter. See if that smooths it out a bit.

  • I notice it a lot more with shades of grey. It does not look good at all. I tried the blur, but it only made it worse.

  • Ultimately, I don't think there's much that can be done about it because the stepping is a result of the resolution. I'm assuming that the clip you showed is a zoom-in on an area of the canvas which would make the stepping more pronounced. How will the illustration be viewed? Online? At what size and at what resolution? Is it for print? The stepping would average out in offset printing. View the illustration at the size others would view it.

    Something else to try would be to add some noise to the areas to mix the pixels up a bit.

    Add a layer of noise above the suit with a mask so it covers just the suit. Use overlay as a blend mode and adjust the Opacity of the layer until it wipes out the steps.



  • @garlam Interesting results with the noise. The picture you are seeing is at 100% size, no zooming. I'll be posting it online at 150 dpi when finished so i might not be that noticable.

  • I'm curious about how you got that effect. That layer option for me doesn't have many options. How do i get that panel? Do you have EX?

  • it's not an EX feature. First, make a selection of the suit with the wand or color gamut. Then go to Layer>New Layer>Tone. From there you'll get a window to make tones. Don't bother adjusting anything yet (you'll adjust all of those settings in a moment); just click OK. The Tone layer you have now is not what you want so let's change it. Open the Layer Property Palette (Window>Layer Property). When that Palette opens, Tone will already be selected (as long as you are on the Tone Layer). Go to Dot Settings and switch it to Noise. Number of Tone Lines will disappear because it doesn't apply to noise tone. The settings you will want to adjust is Density, which will give you your level of gray, and the Noise Size (which I think you will want pretty small - you will want more of a sand than a noise)

    From there, switch your Layer Mode from Normal to Overlay (on the Layer Palette) and adjust the Opacity until the steps disappear.

  • I will try that, thanks for the help

  • @DVD201 This has more to do with the color depth than the resolution. That artifact would go away when working with a 16bit rgb image instead of 8bit. It don't even know if Manga Studio has the option to use 16bit, tbh.

    But... HOLD ON, because it may even not be there in an 8bit image! It may just be showing in the working preview and not in the final image. This is a very typical texture compression artifact from 3d cards. The CSP preview uses the 3D card to speed up the visualization and the card may have texture compression enabled, so the artifact may be created by the 3D card.

  • I mean. Try exporting your image and visualize it from a different program to verify it is in there for real.

  • CSP exports at 24 bits and requires at least 16 bits from the display. The user manual claims that the color layer has a bit depth of 32. I've never noticed any reduced bit depth on the working canvas as compared to the exported image (I would imagine, if there were, people would have lost their minds about it by now). But since doing the gradient test to compare the results with the air brush I've noticed that on other devices, the steps aren't there (on the image I posted above). Then I realized I did that test while using the laptop to watch a movie on the TV screen. On the TV screen, the steps are pretty apparent, but on an iPad, computer monitor, smartphone, and so on, it's pretty smooth. The steps in the original image aren't even that bad on these other devices.

  • @garlam There may be a difference between the depth the program uses to preview than it uses for the real image processing. Could also be the openGL setting generated by CSP being optimized for speed if the card isn't very powerful or even the 3d card settings overriding the program settings. Can even be a monitor limitation. It's a mess, tbh.

    In any case, if CSP is working the real image at (at least) 16 bit depth I'm confident the artifact isn't really in there, but just in the preview. Should be careful to use 16bit at exporting it if it's for printing, but that's all.

  • @garlam said in Blending artifact Pixelation issue:

    CSP exports at 24 bits and requires at least 16 bits from the display. The user manual claims that the color layer has a bit depth of 32.

    Gman is in fact talking about 8-bit and 16-bit per component (per RGB channel) which means:
    8-bit per component = 24-bit (8x3) or 32-bit if you add the alpha channel (8x3+8)
    16-bit per component = 48-bit (16x3) or 64-bit if you add the alpha channel (16x3+16)

    8-bit uses 256 (2^8) values per channel which produces 16 777 216 colors
    16-bit uses 65536 (2^16) values per channel which produces...well, too many colors

    Now, most screen available today are 6-bit panel which uses dithering and Frame Rate Control (FRC) to emulate 16,2 million colors

    More expensive panels are real 8-bit panel (24" monitor >400€, maybe a bit less).
    The best panel can be also 10-bit (1024 values par channel, 1 073 741 824 colors available) but only few programs are able to display the 10-bit color depth and it is needed to use a professional graphic card.

    So, you will probably stick with only 8-bit display at best.

    Now, dithering is used to reduce the banding artifact, it uses a kind of noise to smooth color transition. The Photoshop brush engine uses the dithering when working on 8-bit image and the irony, because of the display limitation, you will probably notice more banding artifact on 16-bit image than on 8-bit image using Photoshop because 16-bit doesn't need anymore any dithering.
    Now, the Clip Studio Paint brush engine doesn't use dithering unfortunately.