Match Lighting Across a Product Catalog

Write a retouch plan to make a set of product photos share one light, without making them look like plastic. SET How many images: [N] The reference frame: [WHICH FILE] Product: [WHAT] Background: [WHITE | SCENE] What is allowed to change: white balance, shadow direction consistency, exposure. What is not: the product color if it is a different SKU, texture, labels. PLAN 1) Measure the reference: highlight, shadow, and a neutral patch, in numbers I can re-use. 2) For each file: match white balance first, then exposure, then shadow softness. Say when a file was shot with a different light position and should be reshot instead of painted. 3) The batch method in Photoshop or the tool I name: adjustment layers, not baked per-pixel painting, so a SKU can be re-opened. 4) A contact sheet check: squint test, and a known failure (one image still warmer). 5) Export: sRGB, the long edge, sharpening for web only. Do not recolor a SKU to match a different SKU.