Canvas resize makes image blurry

[digorydoo]

Steps to reproduce

• Create a new document, 64px * 64px
• Use the pixel pen and draw a few straight lines
• Choose "resize canvas" from the menu
  • Resize to 77px * 77px
  • Set the alignment position to the centre

Expected behaviour

• Since I'm resizing only the canvas and not the content, the content should be left untouched
• The top-left corner of the content should align to a pixel, not a sub-pixel

What I see instead

• The whole document becomes blurry
• The reason is probably that centring a 64px in  77px canvas results in a sub-pixel alignment

[Old Bruce]

Yes, it is geometry and arithmetic making things blurry. I would do two resizes the first anchoring the top left and the second anchoring the bottom right. This will keep the pixel alignment. 64 -> 70 then 70 -> 77 pixels. This means one pixel off centre though.

[Joachim_L]

2 minutes ago, Old Bruce said:

Yes, it is geometry and arithmetic making things blurry.

A source of frustration / confusion IMO. Photoshop adds silently a "missing" full pixel without blurrying the image.

[walt.farrell]

4 hours ago, digorydoo said:

The top-left corner of the content should align to a pixel, not a sub-pixel

If you wanted the top-left corner to remain on a pixel boundary, why did you tell the application to add 6.5 pixels to each edge of your canvas? In order to follow your instructions, your existing artwork must move to a sub-pixel alignment.