Why WhatsApp photos look soft
A photo sent in a WhatsApp chat is usually a smaller copy. A Chest keeps the uploaded file.
WhatsApp is built for a conversation. A photo sent in that chat is usually recompressed so the message stays small. The result looks soft when you open it later on a large screen.
Sending the image as a document can keep a larger file, but the photo still lives in a scrolling thread. OurChest is not a chat. It stores the file the phone uploaded and does not make a smaller copy for the Chest.
What OurChest does not promise
OurChest does not pull photos out of WhatsApp, and it does not claim a specific WhatsApp bitrate. If the phone already uploaded a small copy, that small copy is the file OurChest stores.