We have learned from previous contributions that the best method for the post-stabilisation of action cam clips always makes use of the RAW material from the action cam. Thus, for example, internal camera image stabilisation based on hardware reduces the quality of the video material to such an extent that post-editing with software solutions such as Mercalli V4 SAL+ no longer makes sense.
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What is true for internal camera image stabilisation based on hardware can be transferred to other software stabilisations: A proDAD user recently approached our customer service because the stabilisation of his videos by the GoPro Hero 3 Black Wide with Mercalli was not very effective. The reason was that the RAW video was not used, but rather videomaterial edited with other video editing software.
Once the customer directly optimised the unedited video footage with Mercalli V4 SAL+, this resulted in fantastic shots and a breathtaking video of the helicopter flight from Las Vegas to the Grand Canyon. The selection of the appropriate camera profile also turned out to be a useful addition. Mercalli V4 SAL+ was thus able to correct the fish-eye effect and straighten the horizon of the video.
If you would like to view the original clip of GoPro Hero3, the change made by the stabilisation with Mercalli and the video without fish-eye effect thanks to DeFishr, you can find it here:
For more about the video and just how it was edited, you can turn to the action cam film makers themselves. You can ask questions and share experiences in these forums: