I believe that tutorial for batch editing and creating an action for contrast is the correct way to add contrast to multiple images.

For that tutorial, you will need to first create the contrast action and then select that action when doing the batch.

I think creating the custom action is the right way. I would make sure the contrast adjustment is on a separate layer and not an image adjustment. You can then go through the files and adjust the filters if need be.

The only downside of this is that every image will use the same contrast adjustment.

I believe that tutorial for batch editing and creating an action for contrast is the correct way to add contrast to multiple images.

For that tutorial, you will need to first create the contrast action and then select that action when doing the batch.

I would make sure the contrast adjustment is on a separate layer and not an image adjustment. This will let you adjust the contrast filter once applied to all images in the batch.

The only downside of this is that every image will use the same contrast adjustment.