Crop setting - user defined

[Rainieria]

I've several thousand images to process. Camera "scans" of transparencies.

Each inevitably has a border as it comes out of the camera, so each needs cropping.

After processing a fair number I know the exact pixel width and height that gives satisfactory results.

To save me the effort of having to choose "Unconstrained" + handle dragging on each one OR entering the known dimensions each time, I want a user defined option in the "Mode" dropdown list (preferably one that can be positioned at the top of the list.) I need a means of seriously reducing the number of keystrokes.

Presets are not a viable method, choosing from a long dropdown (thousands of times) isn't an option - even if one could figure out a way of adding one's own preset.
Macro doesn't work because entering the dimensions into the boxes doesn't constitute a command so nothing is recorded in the macro until one actually crops. (I'd want to be able to move the crop area slightly each time just to ensure it's central)

Can anyone suggest the best solution - or have I hit on a desirable new feature "User defined crop dimensions"?

[Alfred]

7 minutes ago, Rainieria said:

Presets are not a viable method, choosing from a long dropdown (thousands of times) isn't an option - even if one could figure out a way of adding one's own preset.

You can add your own presets quite easily, and you can shorten the list by deleting any presets that you don’t need.

Affinity Photo Help: Cropping and straightening

[walt.farrell]

2 hours ago, Alfred said:

You can add your own presets quite easily,

But only for ratios, not for dimensions. Still, it helps.

@Rainieria: If you setup a custom ratio, you can save it as a Preset for cropping. When you select that preset, you will get a crop box that is as large as possible with that ratio. You can then move it to compose the image you want, and complete the crop.

[Alfred]

3 hours ago, Alfred said:

You can add your own presets quite easily,

 

13 minutes ago, walt.farrell said:

But only for ratios, not for dimensions.

The Help page says:

Quote

Absolute Dimensions—Use the adjacent input boxes to set absolute dimensions for the crop area. Set your Units if needed. Can be saved as a preset.

 

[walt.farrell]

21 minutes ago, Alfred said:

The Help page says:

Quote

Absolute Dimensions—Use the adjacent input boxes to set absolute dimensions for the crop area. Set your Units if needed. Can be saved as a preset.

 

There has not been an Absolute Dimensions crop mode since sometime before 1.8. The only current crop modes for Photo are Unconstrained, Original Ratio, Custom Ratio and Resample (which replaced Absolute Dimensions).

[Alfred]

3 minutes ago, walt.farrell said:

There has not been an Absolute Dimensions crop mode since sometime before 1.8. The only current crop modes for Photo are Unconstrained, Original Ratio, Custom Ratio and Resample (which replaced Absolute Dimensions).

I concur! The online Help needs updating.