How to improve the quality on a thermal printer?

Question

C++ / C#

Sending a picture to a thermal printer for printing
. Mercury pixel font is used.

But for some reason it "sags", you can see places where the line completely disappears, some words accidentally become bold, what's the matter?

On a normal printer, there is no such problem.

Through another program (purchased), everything prints well

dсocument.PrintController = controller;
dсocument.DefaultPageSettings.Margins = new Margins(0, 0, 0, 0);
dсocument.PrinterSettings.DefaultPageSettings.Margins = new Margins(0, 0, 0, 0);
dсocument.DefaultPageSettings.PrinterResolution.Kind = PrinterResolutionKind.High;
dсocument.PrintPage += PrintPageHandler;

private void PrintPageHandler(object sender, PrintPageEventArgs args) {
            var size = args.MarginBounds;
            var page = pageList[0];

            var image = CreatePageImage(page, size.Width, size.Height);

            args.Graphics.DrawImage(image, size);
        }

Answer 1

Sounds like a problem with the thermal printer itself. Try other fonts