Merging or flattening seems to reduce sharpening effect

[KLE-France]

Hi everyone,

I've recently switched to Affinity Photo and am globally very happy with the program. However, I'm noticing something strange:

The effect of a Live Filter sharpening layer (any of the three: clarity, UMF, high pass) seems to be dampened when I merge the layer down or flatten the image. The effect isn't completely lost, its just reduced, but visibly so.

This isn't a jpeg compression thing, because the reduction is visible there in Affinity Photo, before any exporting or saving.

I'm on a Windows 10 system, if for some reason that should be important.

I've tried putting the sharpening filter immediately above the pixel layer, putting it at the very top, merging each layer as a separate step, just exporting without flattening...

Am I doing something wrong? Has anyone else observed this? And if so, is there a workaround for it?

Thanks to all in advance!

[MEB]

Hi Kerwin,
Welcome to Affinity Forums
Affinity Designer/Photo uses mipmaps - lower resolution versions of the image - to improve its performance when rendering images on screen at zoom levels below 100%. So what you see on screen is the result of those filters/adjustments being applied dynamically to the lower resolution versions of the image/objects (depending on the zoom level). When you flatten/merge them in some way the filters/adjustments are backed to the full resolution image instead thus the differences you are seeing between the two. To prevent this from happening and get an accurate "preview" of the filters/adjustments make sure you are seeing/checking them at 100% zoom or more to ensure they are being applied/previewed using the full resolution version. 

[KLE-France]

Tested and confirmed!

Indeed with the image at 100%, it doesn't change between the pre and post-flattened rendering.

In hindsight, this shouldn't have surprised me, since images in my (other) raw editor need to be at 100% to see the effects of sharpening.

Anyway, thanks for your very rapid reply!