Answer
Enable Photoshop’s **Maximum Compatibility** option when saving PSD files that will be opened by teammates using older releases. This stores a flattened composite inside the file, allowing those older versions to display layer effects, adjustment layers, and smart objects as they appear in the current version.
Confirmed facts
- When Maximum Compatibility is **enabled**, Photoshop writes a full‑resolution flattened composite image and additional data blocks that older Photoshop releases can read, preserving the visual appearance of layers.
- When the option is **disabled**, the PSD contains only the native data structure; older versions lack the code to interpret layer‑effect properties introduced after their release, so those effects may be dropped or altered.
- Features that depend on functionality introduced after the target older version (e.g., 3D layers, artboards, certain newer smart‑object filters) remain unavailable even with Maximum Compatibility enabled.
Likely explanation
The most common layer‑based features that lose fidelity when Maximum Compatibility is off are:
- Layer styles (drop shadow, inner glow, bevel, stroke, etc.) that rely on newer rendering parameters.
- Adjustment layers that use newer blending modes or properties (e.g., Selective Color, Color Lookup).
- Smart objects containing filters or transformations introduced after the older version’s release.
- Vector‑based shape layers with newer path‑operation attributes.
Enabling Maximum Compatibility typically increases file size by **≈30‑50 %** for a typical PSD that contains several adjustment layers and smart objects, because a full‑resolution flattened copy of the document is stored alongside the native data.
Practical steps for a team
- Identify the oldest Photoshop version that any team member will use to open the file.
- If that version is **CS2 or newer**, enable Maximum Compatibility when saving the PSD; this guarantees that layer effects, adjustment layers, and smart objects will appear correctly.
- If file‑size growth is a concern, consider one of the following mitigations:
- Save a separate, flattened copy (e.g., TIFF or JPEG) for review while keeping the master PSD with Maximum Compatibility enabled.
- Convert non‑essential smart objects to raster layers before saving, if the source assets are archived elsewhere.
- Use Photoshop’s “Save a Copy” option with Maximum Compatibility enabled only for the files that need to be shared.
- Before distributing a batch of files, open a representative sample in the target older version and verify that the Layer Style dialog shows all expected effects.
Missing diagnostic detail
To give a definitive recommendation, we need to know the **exact older Photoshop version** (e.g., CS6, CC 2015, CC 2018) that teammates will use. The version determines which newer features are inherently unavailable, which influences whether enabling Maximum Compatibility alone is sufficient or if additional workflow adjustments are required.