Bent U.

Affinity Designer obviously supports 3 decimal places. If I set 95.987 DPI, I get what I need, which is 3779 pixels per meter. Perfect! Thank you all for your efforts.

Okay, I got it. The resolution in PNG files is always stored in pixels per meter, as an integer. 96 DPI corresponds to 3779.5275590551181102362204724409 dots per meter. Affinity Designer saves this as 3780, and paint.net saves 3779.

Sample_96_DPI.zip

I would like to believe that paint.net is wrong, but the fact is that I can set 96 DPI in paint.net, and then the images are displayed correctly in my software.

Hi MEB, thanks for your reply. I have attached a sample file. Paint.net is the program I use to correct the resolution (CTRL+R - Resize). There you can also see the wrong resolution of 96,01 DPI. As I said I use my images to build them into my own software and in Microsoft Visual Studio I can also see the wrong resolution when I use the debugger. Unfortunately IrfanView does not help in this case, because it only shows the resolution as integers (horizontal and vertical). Sample_96_DPI.afdesign

If you export an image with 96 DPI as PNG, the PNG file has a wrong resolution, namely 96.01 DPI. This makes all my images unusable because I am a software developer and use the images in my software to display them in the GUI. I am dependent on the correct resolution. As long as the error is not fixed, I have to correct the resolution in a different program every time afterwards. This is very annoying.

Hi Sean, thanks for your reply. Maybe you're right and Paint.Net's DPI display is faulty. BUT everything works great with PNGs saved with Paint.Net or exported with Microsoft Expression Design (what I used for many years). Only Affinity Designer's PNGs are giving me trouble. When I open them in Paint.Net, set DPI to 96 and save again they work perfect. Please look at the attached screenshot of my Microsoft Visual Studio Debugger. It displays properties of a PNG that comes from Affinity Designer. In my App I could use a function of Microsoft's programming interface to force DPI values of embedded PNGs to 96, but that is a poor solution which decreases runtime performance.

As a software developer (and graphics designer) I am creating the graphics needed for my Windows desktop apps all by myself. And I need them with a (screen) resolution of exactly 96.00 DPI. Document settings in Affinity Designer are 96, but in fact PNGs are exported with a sligthly different resolution of 96.01 DPI - not good. For now I have to correct DPI settings of every exported image in a separate tool (for example paint.net).