Different line thicknesses in PDF Photoshop, how to fix?

Question

Adobe Photoshop

Hello.
There was a need to add a small table to the presentation in Photoshop. But when exporting a PDF file, the lines drawn by a rectangle with the same thickness are suddenly distorted and become different. You can see it on the screen.
Tell me how can I fix this?

As you can see, some lines are even darker, although in Photoshop everything is the same color and thickness.

Answer 1

It looks like this because the lines have antialiasing around the edges.
There can be many reasons for this: from the fact that you are not viewing this PDF at 100% scale, or what format is used to store the image inside the PDF (there can be many different ones), to how exactly you drew these lines (for example, without pixel alignment or by setting the thickness not in whole pixels, but in some fractional points).
However, the fundamental reason is the same: this task should not have been done in Photoshop, it should have been done in Illustrator, because PDF works best with vector images, not bitmaps. (Which does not mean that you can also walk on your head with thick lines and expect a perfect image.)