Paint.net is the only app that is blurry on my Windows 11 laptop

[PaintJunky]

    After a few crashes and hiccups, I finally started using my new Lenovo Windows 11 laptop. I am not computer savvy, but Paint.net is one of my favorite tools. I use it to cleanup old scanned documents (tiff). Everything worked fine on win7… meaning the image I saw on paint.net matched the quality of the image in its saved format (tiff, pdf, png, etc).

    On win7 I could see if the document needed clarifying or dust removal, but in win11, I can’t detect those slight nuances. Also, on windows 11 the image could look clear and sharp in its original format, but blurry when I open it on paint.net.

    I purposely attached a document that needed no editing to show you the difference. I tried the most recent suggestions, but nothing worked.

 

[toe_head2001]

This was changed in Paint.NET v5.0.4 to make the image more accurate at different zoom levels.

 

Quote

• Improved: The rendering quality of the canvas area has been greatly improved
  • Gamma correction is now used for mipmap generation and compositing, ensuring consistent luminance (brightness) and higher quality antialiasing.
  • Multisampling is now used for antialiasing, which eliminates pixelation distortions when zooming in, and greatly reduces aliasing artifacts when zooming out.

 

[_koh_]

Technically, 50% zoomed texts should look 50% thinner, not 50% smaller texts with the same thickness.

Not so many image viewers handle this properly, and PDN is the most accurate one I know of.

 

You can spot the noise because non gamma correct down scaling enhances the noise.

So if you want to use down scaling for this purpose, hit Ctrl+R and uncheck gamma correction then you can create a noise enhanced image.

[Rick Brewster]

What they said.

 

This isn't a case of the canvas now looking blurrier. It's a case of mismatched expectations. You (and so many others!) are accustomed to the wrong way of how things used to be presented, such that the correct way actually seems wrong to your eyes. It'll just take a little getting used to, but rest assured things are working correctly and optimally.

 

When gamma correction is not used, it results in the image being darker and having increased contrast. This is incorrect, but can be subjectively pleasing to the eye. 

 

2 hours ago, _koh_ said:

Not so many image viewers handle this properly, and PDN is the most accurate one I know of.

@saucecontrol deserves a lot of credit here -- he has been an unwaveringly patient mentor in this space, and I would not have been able to figure it out without his help and without his MagicScaler library

[_koh_]

2 hours ago, Rick Brewster said:

@saucecontrol deserves a lot of credit here -- he has been an unwaveringly patient mentor in this space, and I would not have been able to figure it out without his help and without his MagicScaler library

 

This scaler is really high quality. Not only it's gamma correct, it almost has no moire pattern at any zoom level.
I found latest IrfanView does gamma correct scaling, but I still see some moire so likely sampling is not as good or a bit more aggressive.

[Rick Brewster]

1 hour ago, _koh_ said:

it almost has no moire pattern at any zoom level.

 

Is this for the interactive canvas, or only for Image->Resize?

 

The canvas is using a combination of MagicScaler for mipmaps, and then Direct2D for presentation.

 

Mipmaps via MagicScaler uses the Average (aka Box) interpolator kernel. For edge tiles that aren't the right size (e.g. not 2^n) it'll use a Linear interpolator kernel (same as Image->Resize's "Bilinear").

 

As for drawing it to the screen w/ Direct2D, I found that Linear sampling was too sharp, MultisampleLinear was too blurry, but a 50/50 blend between the two just felt perfect.  When "very close" to a power of 2 (e.g. 50%, 25%, 12.5%, ...) it will only use Linear. (this is all just heavy enough that I need to drop the MultisampleLinear when hardware acceleration is disabled -- it'll just use Linear).

 

So if you're talking about the canvas then it's a combination of all these things working together. Also, starting with v5.1, the whole rendering pipeline (after layer composition) is fully floating-point and uses linear gamma. (5.0 also uses linear gamma but has to bounce back and forth between floating-point/linear and integer/companded, for various reasons)

[_koh_]

2 hours ago, Rick Brewster said:

Is this for the interactive canvas, or only for Image->Resize?

 

I'm talking about canvas so it's due to your configuration.

 

Since PDN supported it, I was looking for a simple image viewer with gamma correct zoom. IrfanView is the only one I could find but the quality is not as good as PDN.

An image viewer needs to do interpolated upscaling, so maybe they are using uniform method for both upscaling and downscaling.