Layer > Merge Selected creates blurry image

[Efvee]

I have noticed a strange blurring effect when using Layer > Merge Selected.

This does not happen with Layer > Merge Visible

In the video below I am pressing Cmd+Shift+E and Cmd+Z to show the effect.

There should be no visible difference at all between the unmerged view and the merged.

It may be related to this issue: 

MacOS Catalina 10.15.2

Affinity Photo 1.7.3

Radeon VII GPU

Edited February 13, 2020 by Efvee

[Chris B]

Hey Efvee,

It does look similar. I think when you do Merge Selected, whichever layer is selected is used as the candidate layer and I am not sure if this is why we get different results to when we just Merge Visible. I will need to look into this some more...

[edit]

Hello! Have this issue been adressed? I am experiencing the same thing. I used the "merge selected" command a lot of times in the attached file, so when u slide through the history it shows the blurring effect.

Z01.afphoto

[walt.farrell]

1 hour ago, edit said:

Have this issue been adressed? I am experiencing the same thing.

The "issue" is often that the file contains layers that:

• Are not located on integer pixel coordinates, or do not have integer pixel sizes;
  or
• Do not have the same DPI as the document (or as the layer you're merging into).

If blurring occurs in those situations, the solution is to fix the size or location or DPI of the layers that you're merging, as the blurring is expected, and not the result of a program bug.

Most of your pixel layers are not located on integer pixel coordinates, and the ones I looked at have DPIs that do not match the document DPI.

To see their coordinates, activate the Move Tool, select the layer, and look in the transform panel. You may need to adjust your Photo Preferences, User Interface section, and increase the number of decimal places displayed for pixel measurements to 3 or more (I often use 6).

To see their DPIs: if you have Publisher you can open a copy of the file in Publisher, select a layer, and use Layer > Convert to Image Resource. You will then get an additional control in the Context Toolbar that will give you the layer's current DPI and size.

To fix your layers:

1. If you activate Snapping, and in the Snapping options enable Force Pixel Alignment and disable Move by Whole Pixels, you can nudge a layer onto a pixel boundary.
2. You can Rasterize a layer (Layer > Rasterize, or right-click on it in the Layers panel and choose Rasterize), and it will take on the document DPI.

Try that in a copy of the document first, of course. But once you have fixed those problems you should find that merging works better.