It sounds like you have used the Default Template which is uncompressed. Why are you rendering it to your hard drive? (i.e., what is the final destination?) and render it with a template that is appropriate for that destination. e.g., if it’s Blu-ray disc render to M2T ot AVC, if it’s the web render to MP4, if it’s a DVD render to MPEG2, etc.
~jr
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