A dark mark on a pale surface and a similar mark on a darker surface can create different visual impressions. Record the starting appearance before comparing sample contrast, especially when pieces come from different batches.
Capture a baseline
Photograph each identified specimen before testing, using the same background and lighting arrangement you intend to use later. Note obvious color variation, grain or surface marks. Keep the original image with the specimen record rather than choosing a more flattering substitute photograph.
After an appropriately documented test, photograph the same area again under comparable conditions. If exposure or lighting changes, label that difference. Do not interpret an automatic camera adjustment as a measured improvement in engraving performance.
Compare like with like
Keep the untested appearance visible beside the result. Discuss what changed on that specimen, and list variables you could not hold constant. These notes can support a careful AntBelt G1 project discussion, but they are not material approval or a guarantee for another surface. Confirm material suitability separately before any test.
Browse related planning notes in /updates/.