RTI of registered will

If you prove the son of the testator then you can apply for certified copy of the registered Will by producing the legal heirship certificate and dearth certificate instead of going thorugh RTI route. 

Applicatiobn submitted invoking RTI act will not be entertained because as per provisions of Registration Act any information regarding document registered with the title as 'WILL'  cannot be disclosed to anyone.

You can apply for a certified copy of the Will by enclosing a copy of your father's death certificate.  However, RTI does not work for this purpose.

Apply for inspection of requisite document for relevant details and apply for certified copy.