If I have iCloud photos turned off and switch my Apple ID will I loose my photos?

AFAIK. If you switch Apple IDs, then in theory, the two libraries merge on the switched iCloud account. Photos on your iPhone will, after first syncing, will contain all the photos that were in both libraries, and will do the same for any of your other devices that are signed in with that Apple ID that have iCloud Photo Library enabled. On the other hand, the photos stored in the cloud for your other Apple ID will remain unchanged ... unless you switch IDs again.