Convert PDF to tiff image using SDK

I'm trying to convert PDFs to single-page tiff using the Adobe SDK using C#, but I'm confused on several points.  I've searched this forum but still have questions.

- Do I need to have Adobe Acrobat Reader installed on my computer to accomplish this?  Or can I accomplish this WITHOUT having to drive the Acrobat Reader's GUI app?  In other words, I don't want to open the Adobe user interface and start driving the GUI app that way.  I just want to have my C# program open a PDF file

and export it to tiff, with nothing visible on the screen.

- Which of the SDKs should I use?  

    - Acrobat DC SDK

    - Acrobat XI SDK

    - Acrobat X SDK

I downloaded sample probjects for each but they have a project reference to "acrobat" which isn't a dll present

in the samples directory.   Is that because I'm supposed to have the Acrobat Reader installed on my

machine, and the project is referencing a Registry based COM dll?   I don't want to use COM if possible.

Some of the online articles I've found refer to JaveScript in their discussions of such a C# project. But I'm not using Javascript and I'm not writing a web app (which is what I think of when I think of JavaScript.)  This is a C#/.NET desktop/thick-client app, not web browser based. 

Does using the Acrobat SDK necessarily cost money?   Or can this be done completely free (legally) using the Adobe/Acrobat SDK?  I want to use the Adobe SDK because other PDF converting software inevitably runs into problems with a particular PDF file here and there.

Any help greatly appreciated.

Thanks,

Gerry