How can I color a logo without getting it so pixelated?

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Colored Vector Layers

You probably lose the careful antialiasing put in place the first time (pixels of different colours to soften the edges).

I would recommend using Solid Color Layers (Layer > New Fill Layer > Solid Color) clipping masked to the logo.

There are quite a few ways to do it. But since they are very solid colors, it's quite easy with the Hue/Saturation Adjustment filter.

• Add the Hue/Saturation Adjustment filter on a layer above your image
• Click on the little hand in the upper left area.
• Use the hand cursor to click on one of the colored letters and drag a little to the right or left. either. Doesn't matter.
• Now you can use the sliders to change that color and brightness to whatever you want.
• Repeat for the other colored letters.

But it is a very low resolution file you have here. If this is all you have, you should recreate it as a vector image in Illustrator so that it can be scaled to any size you might want without losing any resolution. And you can also change the colors at will to all of it easily.