Halftone Filter :: Layer Opacity below 100% –> Artefacts on Export

[thomaso]

I experience squared artefacts when a halftone live filter is applied to an object with reduced layer opacity. The PDF version does not seem to matter, and, oddly, with identical export settings the artefacts occur differently on various exports.

The issue appears not to be caused by Hardware Acceleration and occurs with both performance settings.

It feels like a bug but I still stick to V1 which does not get bug fixes any more. So maybe a V2 user might want to try this document and possibly create a V2 bug report.

  halftone layer opacity.afpub

 

[lepr]

still broken in 2.0.3 on Intel Mac

[David in Яuislip]

Works if the object is 100% opacity, grouped and the group opacity is 50%. PITA and seeems like a bug to me. Publisher V1, Windows 10

[thomaso]

Thanks to everybody for testing and confirming.

I just noticed another issue* in V1 with a (halftone) Live Filter:   *EDIT: see the solution in the post below

1. Create two objects.
2. Select one and apply a (halftone) live filter to make it nested in the selected object.
3. Duplicate the filter via cmd-/ctrl-J.
4. Move the copied filter as child layer inside the other object.

Now this copied filter does not appear in the Layers Panel if the layer is displayed collapsed. – Again I wonder whether this happens in V2, too?

Edited January 1, 2023 by thomaso

[lepr]

4 minutes ago, thomaso said:

Now this copied filter does not appear in the Layers Panel if the layer is displayed collapsed. – Again I wonder whether this happens in V2, too?

There isn't a bug in your example.

The initial filter is mask-nested in the triangle, therefore it is shown when the parent is collapsed.

The duplicate filter is clip-nested in the ellipse, therefore it is not shown when the parent is collapsed.

If you drop the filter on the thumbnail, instead of the name region, of the target, then the filter will become mask-nested instead of clip-nested, and so it will show when the parent is collapsed.

[thomaso]

4 minutes ago, ,,, said:

The initial filter is mask-nested in the triangle, therefore it is shown when the parent is collapsed.

The duplicate filter is clip-nested in the ellipse, therefore it is not shown when the parent is collapsed.

Ah, that's it indeed, thank you!

[lepr]

6 minutes ago, thomaso said:

Ah, that's it indeed, thank you!

You're welcome, and Happy New Year!

[Old Bruce]

3 hours ago, MC909 said:

I tried your file in v1 and v2 and it happens in both.

Only thing that works for me is to rasterise the layers with the Halftone filter before export, which is probably not ideal.

@thomaso, This has do do with your original post.

I get the same thing in version 1 and version 2

However if I set the opacity to 100% and make a group and set the group to 50% then it exports fine.

[NotMyFault]

in Case you want to use halftone filter for vector objects:

1. create a rectangular shape in size of document (artboard), plus the radius of halftone, assign color or fill as needed
2. nest halftone filter to rectangle
3. duplicate as needed for multiple objects
4. nest vector shapes in masking position, or use mask layers. Set opacity of nested layer as needed.

this avoids color casts and other color artifacts at edges where black is used for transparent areas as color for halftone filter.

 

[Old Bruce]

1 minute ago, NotMyFault said:

4. nest nectar shapes in masking position, or use mask layers.

Mmmmm... nectar.

[NotMyFault]

1 hour ago, Old Bruce said:

Mmmmm... nectar.

Typo already consumed corrected

[thomaso]

2 hours ago, NotMyFault said:

this avoids color casts and other color artifacts at edges where black is used for transparent areas as color for halftone filter.

I don't see a connection with the square white artefacts in this topic. – Possibly you confused it with that recent thread?

https://forum.affinity.serif.com/index.php?/topic/177460-halftone-live-filter-with-wrong-assumptions-on-borders/

[NotMyFault]

1 hour ago, thomaso said:

I don't see a connection with the square white artefacts in this topic. – Possibly you confused it with that recent thread?

https://forum.affinity.serif.com/index.php?/topic/177460-halftone-live-filter-with-wrong-assumptions-on-borders/

Not confuse, intensional connection. 

The method I suggested solves both problems:

1. The issue from your post Wrt light rectangles
2. the issue wrt to wrong edge colors

i added a copy of your rectangle, adjusted the size, see below:

[lacerto]

Another workaround would be using color (or swatch) opacity assignment for each object where halftone filter is applied.

[thomaso]

Thank you everybody for the various workarounds (group | rasterize | colour opacity | mask) – while only the masking, multi-object / multi-nesting method of @NotMyFault seem to cover the squared artefact AND the shape edge problem (that I did not care when opening this thread.

But after all, don't you agree this to be a bug (regardless of workaround options), especially since it does not display the artefacts in the layout window / inside Affinity but on export only (≠ WYSIWIG)? If the squared artefacts are a must-have because of technical reasons wouldn't a proper interface disable (gray-out) the layer opacity option for such an object?

15 hours ago, NotMyFault said:

The method I suggested solves both problems:

I still see a third problem with the halftone filter: it always seems to be related to the document, not the object it is applied to: If I move the object the halftone pattern does not move but change, displaying another detail of the raster grid. Same if I rotate the object … while scaling does work as expected. This happens regardless of the used layer setup (single / grouped / masked).

So does one have an idea how to link the halftone pattern position & rotation with the object – without rasterizing or the additional need to adjust rotation in the filter options separately?

[NotMyFault]

Totally agree it is a bug.

wrt to third problem: and no, I could not find a way to set point of origin in filter parameters. On iPad, using touch or pen is always setting radius or other parameters.

[Callum]

Hi All, sorry for the delayed response to this thread. I have logged this with our developers for further investigation.

Thanks
C