What are D/P at sight and D/P after sight? Which is more favourable for the exporter?

What are D/P at sight and D/P after sight? Which is more favourable for the exporter?

D/P at sight requires immediate payment by the importer to get hold of the documents. D/P after sight gives the importer a certain period after presentation of the documents, but documents are not released to him until he actually pays for the merchandise. D/P at sight is more favourable for the exporter.