Yes—large TIFFs are normal, especially if they’re 16-bit, uncompressed, and still contain layers. A RAW file is compact because it stores sensor data efficiently; a TIFF stores a full rendered image, often with three color channels, so it can be many times larger.

To reduce size without losing quality:

• Use TIFF compression such as LZW or ZIP. TIFF compression is lossless.
• Flatten the image before saving if layers are not needed by the printer or client. Layers can make TIFFs huge.
• Keep the original RAW files for future re-editing. In many cases, the RAW is the best archival source, and final delivery files can be exported as needed.

JPEG is smaller, but it’s lossy and only 8-bit, so it’s not ideal as the master file if she may need to re-edit extensively.

A practical workflow is often: keep the RAW, save edit instructions or project files as needed, and export TIFF only for print delivery or when a high-quality rendered master is specifically required. If she’s saving every intermediate version as a layered 16-bit TIFF, that’s likely the main reason storage is disappearing so quickly.