Undo Brush Inop after DoF blur

[Balveda]

After performing a DoF live filter blur it's impossible to fine tune the blur using the undo brush tool despite selecting an undo brush reference point in the history prior to the filter being applied. I've also checked to see if the problem exists in the current Beta and indeed it has the same problem. Then tried legacy Affinity Photo and yet again same problem. Here's how I went about this, merged visible, selected this action as the source for the undo brush, applied DoF filter, selected undo brush, in order to check functionality it was set to 100% on all counts. Appled undo brush and....Nothing. This technique is something I'd really like to take advantage of and I'm surprised to find the fault stretching back through time. It's hard to see what if anything I'm doing wrong here as it's quite straightforward. Is this something that Photo is incapable of doing? I'd be surprised that it's a bug as it stretches back to legacy product.

[Balveda]

Just now, N.P.M. said:

I guess you merged after the blurring?
If you merge visible it essentially get's rasterized into one new pixellayer but your actions are applied on another layer(the one before merging)
If you want to undo things you should be editing nondestructively.
Applying live blur filters and use the inbuild mask to add or remove parts of the applied filter/adjustment.

No I merged prior to the DoF blur to provide a clean slate to investigate the bug, I selected that merged entry in the history as the source for the undo brush.

[MEB]

Hi @Balveda,
Welcome to Affinity Forums

According to your description "Here's how I went about this, merged visible, selected this action as the source for the undo brush, applied DoF filter, selected undo brush, in order to check functionality it was set to 100% on all counts. Appled undo brush and....Nothing." seems you are trying to apply the undo brush state to a layer with the live Dof filter still nested/applied which means you will not see any changes since the active filter still blurs the state you are trying to apply with the undo brush. To make it work as you want you would need to merge the DoF filter with the layer it's applied to and only after this use the undo brush with the state where the image is not blurred.

As N.P.M mentioned you can get the exact same result painting in the built-in mask of the filter to control where and how much the filter is applied.

[Balveda]

19 minutes ago, N.P.M. said:

IDK,I never use the undo brush because I rather edit nondestructively and edit the mask or delete the mask/refill it or delete the filter/adjustment altogether.
 

Gosh, I was so fixated by the inability to use the undo brush on the blur that it didn't occur to me to use a black brush on the live filter adjustment. That explains why that functionality was ever applied to DoF. Having said that, it logically should work but using a mask adjustment is so much better. Many thanks @N.P.M.

[Balveda]

1 minute ago, MEB said:

Hi @Balveda,
Welcome to Affinity Forums

According to your description "Here's how I went about this, merged visible, selected this action as the source for the undo brush, applied DoF filter, selected undo brush, in order to check functionality it was set to 100% on all counts. Appled undo brush and....Nothing." seems you are trying to apply the undo brush state to a layer with the live Dof filter still nested/applied which means you will not see any changes since the active filter still blurs the state you are trying to apply with the undo brush. To make it work as you want you would need to merge the DoF filter with the layer it's applied to and only after this use the undo brush with the state where the image is not blurred.

Thanks @MEB a previous reply to my post has come up with a much better method to fine tune DoF blur that I really should have thought of myself! A simple mask applied to the DoF adjustment achieves the required results.