Try
MSDN-[How to convert PDF to TIFF through C#][
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From reference link :-
PDFRasterizer.NET
is a component for rendering PDF documents and is written entirely in C#.
This article describes how to use the
PDFRasterizer.NET
component to:
Convert PDF documents to raster images such as BMP, GIF, PNG, TIFF etc.
Display PDF documents in your WinForms application (with and without an EMF)
Programmatically print PDF documents
so Have a read CP article
100% .NET component for rendering PDF documents[
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